Galerucinae Latreille 1802
Creators: name: Viswajyothi, Keezhpattillam
name: Clark, Shawn M.
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Chrysomelidae

description: Key to the tribes, subtribes, and sections of New World Galerucinae Latreille, 1802
(Modified from Riley et al. 2002a)
1. Hind femur usually adapted for jumping, broad, with internal extensor apodeme (spring); if hind femora slender, then prosternum comparatively broad, forming small horizontally flattened area between front coxae; pronotum variable, but often with transverse prebasal groove in basal fourth (this groove is not to be confused with fine sulcus delimiting basal bead); inner wall of epipleuron usually with two elytron-to-body binding patches .............................. Tribe Alticini Newman, 1835 – Hind femur not abnormally broad (except rarely), without sclerotized internal extensor apodeme (spring); front coxae contiguous, or narrowly separated by keel-like prosternum; pronotum sometimes shallowly impressed near base, but never with well-defined, transverse groove in basal fourth; inner wall of epipleuron with single elytron-to-body binding patch ..................................... 2
2. Median lobe of aedeagus with prominent basal spurs (Fig. 148); last ventrite of male abdomen without apical lobe; antennae usually inserted low on frons, beyond middle of eyes; larvae, where known, feeding on leaves .................................................................................................................. 3 – Basal spurs of aedeagus small or absent (Fig. 149); male abdomen variable, sometimes with lobe at apex; antennae usually inserted higher, nearer middle of eyes; larvae, where known, feeding on roots. .................................................................................................4 (Tribe Luperini Gistel, 1848)
3. Posterior-most ventrite of male abdomen usually with median, apical, semicircular depression; abdominal apex sometimes emarginate behind impression; tarsal claws of most genera either simple (Fig. 144) or bifid with narrow, sharply pointed appendage (Fig. 146); anterior and posterior tibiae usually without terminal spurs; larvae feeding on leaves.................................................................... ............. Tribe Galerucini Latreille, 1802: Sections Apophyliites Chapuis, 1875, Atysites Chapuis, 1875, Coelomerites Chapuis, 1875, Galerucites Latreille, 1802, Schematizites Chapuis, 1875
– Posterior-most ventrite of male abdomen without distinct impression, although sometimes flattened; tibiae usually with terminal spurs; tarsal claws of most genera appendiculate, with broad, blunt lobe (Fig. 145); larvae unknown for most genera, but feeding on leaves in at least one genus.............................................................................................. Tribe Metacyclini Chapuis, 1875
4. Last ventrite of male abdomen with rectangular lobe (Figs 198–199) ................................................ ................................................................................................... 5 (Subtribe Luperina Gistel, 1848)
– Last ventrite of male apically rounded or slightly truncate, without lobe........................................... .......................................................................................... 7 (Subtribe Diabroticina Chapuis, 1875)
5. Elytral epipleura extremely narrow, indistinct..................... Section Phyllobroticites Chapuis, 1875
– Elytral epipleura normal, comparatively broad at least basally......................................................... 6
6. Tarsomere 1 of hind leg distinctly longer than 2 and 3 combined; apical lobe of last ventrite of male abdomen large, nearly square (as in Fig. 198); aedeagal orifice covered by sclerotized plate........................................................................................... Section Monoleptites Chapuis, 1875
– Tarsomere 1 of hind leg usually shorter than 2 and 3 combined; apical lobe of male abdomen usually much wider than long (as in Fig. 199); aedeagal orifice variable, but usually without sclerotized covering .......................................................................................... Section Scelidites Chapuis, 1875
7. Mesotibia of male with deep, inner, subapical notch (Fig. 201).. Section Phyllecthrites Horn, 1892
– Mesotibia of male without subapical notch ....................................................................................... 8
8. Tarsal claws bifid, with narrow, sharply pointed inner lobe (as in Fig. 146).................................................................................... Section Diabroticites Chapuis, 1875
– Tarsal claws appendiculate, with comparatively broad, blunt inner lobe (as in Fig. 145) ................ 9
9. Elytra entirely dark, with distinct transverse impression near basal third........................................... .............................................................................................. Section Trachyscelidites Wilcox, 1972
– Elytra often colored otherwise, without transverse impression across basal third .............................. ................................................................................................... Section Cerotomites Chapuis, 1875
Key to the genera of adult Galerucinae Latreille, 1802 of the New World
The following key does not deal with the genera of Alticini. See Scherer (1962, 1983) for keys that enable identification of most of those genera. It is not necessary to know the tribe etc. before using the following key to genera. As evidenced by the preceding key, galerucine classification is largely based on male features, especially those found on the aedeagus. The following key to genera partially reflects this, in that some of the couplets mention only male characteristics. Indeed, users will occasionally be frustrated in their attempts at identification, if only female specimens are available for examination. However, such instances are less frequent than in previously published keys. The principal objective of our key is to facilitate identification, rather than follow phylogeny. In an effort to enable identification of females, as well as males, we usually use characters that are present in either gender. Some of these characteristics are of very little value in classification. Accordingly, genera that key out close to each other might be quite distantly related. Moreover, the superficial characters (such as color) may not always allow for proper generic placement of undescribed species.
1. Hind femora clearly enlarged, except rarely; extensor apodeme present inside hind femur; front coxae of most genera clearly separated from each other by posterior process of prosternum ............ ................................................................................. Tribe Alticini Newman, 1835 (not treated here)
– Hind femora not abnormally enlarged (except in Leptonesiotes, an anomalous genus from Cuba, Fig. 202); extensor apodeme absent from inside hind femur; front coxae of most genera contiguous or very narrowly separated ................................................................................................................ 2
2. Epipleuron extremely narrow along entire length, narrower than width of second antennomere (Fig. 225) ........................................................................................................................................... 3
– Epipleuron wider, at least near base .................................................................................................. 6
3. Tarsal claws appendiculate, with inner appendage broad and apically blunt (Fig. 145); male with terminal abdominal ventrite impressed, with rectangular lobe at apex (Fig. 199); habitus as in Figs 132, 134; distribution in Canada and United States .................... Phyllobrotica Chevrolat, 1836
– Tarsal claws bifid, with inner appendage apically pointed (Figs 146–147); male with terminal abdominal ventrite semicircularly incised (Figs 195, 197), but without median rectangular lobe at apex.................................................................................................................................................... 4
4. Metasternum shorter than basal abdominal ventrite; both pronotum and elytra with well-developed tubercles (Fig. 21); distribution in Costa Rica ..................... Apteroyinga Viswajyothi & Clark, 2020
– Metasternum longer than basal abdominal ventrite; pronotum and elytra not both strongly tuberculate.......................................................................................................................................... 5
5. Elytron with strongly developed carina, beginning at humerus and extending most of elytral length, simulating edge of extremely broad epipleuron (Figs 218–219); elytra with numerous long, erect, comparatively sparse setae, without short, dense, appressed setae (Figs 16–17); distribution in northern South America and perhaps Central America ............................ Socorroita Bechyné, 1956
– Elytron without posthumeral carina; elytra densely covered in very short, dense, appressed setae, in addition to longer, sparser, erect setae; habitus as in Fig. 11; distribution in Panama ......................... .................................................................................................................. Neophaestus Hincks, 1949
6. Elytra with dense, short, subappressed setae, in most species covering entire disc, in some species evident only in basolateral area; in some species, elytral surface obscured by dense setae; basal spurs of aedeagus well developed in most species (Fig. 148)..................................................................... 7
– Elytral setae, when present, rather sparse, long, and erect; elytral surface clearly visible, even when sparsely pubescent; basal spurs of aedeagus either present (Fig. 148) or absent (Fig. 149) ........... 47
7. Tarsal claws appendiculate; inner appendage of claw broad and apically blunt ............................... 8
– Tarsal claws bifid or simple; inner appendage of claw, when present, narrow, with apex sharply pointed ............................................................................................................................................... 9
8. Body larger than 10 mm long; male with distal five antennomeres enlarged, wider than preceding antennomeres; habitus as in Fig. 3; distribution in Brazil .................. Austrochorina Bechyné, 1963
– Body less than 10 mm long; male antennae filiform (Figs 26–27); distribution from Mexico through much of South America ...................................... Itaitubana Bechyné, 1963 [in part; see couplet 25]
9. Tarsal claws simple, without inner appendage (Fig. 144) ............................................................... 10
– Tarsal claws bifid, with sharply pointed inner appendage (Figs 146–147) ..................................... 13
10. Antennomeres 6–10 more elongate than described below; each elytron dark with pale, transverse or oblique band across middle; habitus as in Fig. 8; distribution in Brazil .............. Chorina Baly, 1866
– Antennomeres 6–10 short, each only slightly longer than broad; elytral color pattern not as above.................................................................................................................................................11
11. Pronotal punctures much smaller than those of elytra; body more than 10 mm long; gender either male or female; habitus as in Fig. 9; distribution in Peru and French Guiana ... Syphaxia Baly, 1866
– Pronotal punctures as large as, or much larger than, those of elytra; body less than 10 mm long; gender female (males with bifid claws) ........................................................................................... 12
12. Pronotal punctures much larger than those of elytra; body length usually larger than 6.0 mm; habitus as in Fig. 34; distribution from Canada to Argentina ......................................................................... ....................................................................... Erynephala Blake, 1936 [in part; see couplets 15, 47]
– Pronotal punctures similar in size to those of elytra; body length usually less than 6.0 mm; habitus as in Fig. 35; distribution from Canada to Guatemala ......................................................................... ............................................................................... Monoxia LeConte, 1865 [in part; see couplet 41]
13. Pronotal punctures much larger than those of elytra ....................................................................... 14
– Pronotal punctures not larger than those of elytra, or only slightly larger ...................................... 16
14. Eyes separated from each other by distance greater than length of basal antennomere; pronotum pale, with two dark spots; elytra dark, with sutural, median, and lateral pale vittae; habitus as in Fig. 45; distribution in Hispaniola.................................................................... Gonaives Clark, 1987
– Eyes separated from each other by distance less than length of basal antennomere; color not as above................................................................................................................................................ 15
15. Basal margin of pronotum gently curved from meson to posterolateral pronotal angle; posterolateral angle only slightly more anterior than most posterior part of prothorax; males only (females with simple tarsal claws); aedeagus extraordinarily long, C-shaped, forming complete semicircle in lateral view; habitus as in Fig. 34; distribution from Canada to Argentina ........................................ ....................................................................... Erynephala Blake, 1936 [in part; see couplets 12, 47]
– Basal margin of pronotum very strongly bisinuate from meson to posterolateral pronotal angle; posterolateral angle positioned far anterior to most posterior part of pronotum (Fig. 188); gender either male or female; aedeagus not as above; habitus as in Fig. 40; distribution from Arizona to Costa Rica ................................................................. Ophraea Jacoby, 1886 [in part; see couplet 27]
16. Elytropleuron (lateral area of elytron, just before epipleural ridge) distinctly swollen, in some species coalescing with epipleural ridge and together forming broad, rounded, single costa (Fig. 223) .... 17
– Elytropleuron concave, not or only vaguely swollen; epipleural ridge narrow, normally acutely carinate, although less commonly forming narrowly rounded costa............................................... 27
17. Antennomeres 3–7 compressed or dilated; body depressed; habitus as in Fig. 28; distribution from Mexico through much of South America................................................ Schematiza Chevrolat, 1836
– Antennae filiform............................................................................................................................. 18
18. In many species, elytral pubescence directed in various directions, forming mottled pattern; if elytral pubescence otherwise, then elytra tuberculate, in addition to standard humeral and basal callosities ........................................................................................................................................ 19
– Elytral pubescence not swirling in various directions; elytra not unusually tuberculate ................ 20
19. Proximal male tarsomere of front leg with small ventral tubercle at base (visible only when tarsus bent dorsally, Fig. 204); body of single included species 5–6 mm long (but undescribed or misplaced species may be smaller); habitus as in Fig. 32; distribution from Texas to Guatemala ...................... .......................................................................................................................... Brucita Wilcox, 1965
– Male without tubercle at base of proximal tarsomere; body of most species smaller than 5 mm; habitus as in Figs 29–30; distribution from Mexico through much of South America, as well as in West Indies......................................................... Yingaresca Bechyné, 1956 [in part; see couplet 60]
20. Seventh antennomere with tuberculate protuberance on distal edge (Fig. 215), distinct in males, obsolete in some females; pronotum at least twice as wide as long................................................ 21
– Seventh antennomere without apical tubercle; pronotum in many (but not all) species less than twice as wide as long................................................................................................................................. 23
21. Elytra green with yellow lateral margins; discal elytral costae absent; habitus as in Fig. 43; distribution in South America .......................................................... Chlorolochmaea Bechyné & Bechyné, 1969
– Elytra dark, with pale, slightly elevated, discal vittae ..................................................................... 22
22. Each elytron dark with suture, lateral margin, and two discal vittae pale; habitus as in Fig. 41; distribution in Florida, West Indies, Central America, and South America......................................... ......................................................................................................... Neolochmaea Laboissière, 1939
– Each elytron dark with suture, lateral margin, and three discal vittae pale (Fig. 224); habitus as in Fig. 42; distribution in Argentina, Brazil, and Paraguay ................................. Iucetima Moura, 1998
23. Pronotum and elytra uniformly reddish; habitus as in Fig. 22; distribution in Canada and United States ..................................................... Tricholochmaea Laboissière, 1932 [in part; see couplet 46]
– Color usually otherwise; distribution in Latin America .................................................................. 24
24. Pronotum entirely pale, or dark with pale lateral margins; elytra either entirely dark metallic blue or violet, or dark red with narrow black lateral margin; body 7.5–9.0 mm long; distribution in Colombia and Peru ........................................................................................................ Narichona Kirsch, 1883
– Color otherwise................................................................................................................................ 25
25. Third antennomere distinctly longer than fourth; elytra pale, often with green and yellow vittae (Fig. 222); habitus as in Figs 26–27; distribution from Mexico through much of South America................................................................. Itaitubana Bechyné, 1963 [in part; see couplet 8]
– Third antennomere usually shorter than fourth; if third antennomere longer than fourth, then elytra entirely dark..................................................................................................................................... 26
26. Body at least twice as long as broad, usually dorsoventrally flattened; habitus as in Fig. 31; distribution from Mexico through much of South America, as well as in Lesser Antilles............................................................................. Metrogaleruca Bechyné & Bechyné, 1969
– Body less than twice as long as broad, oval, with dorsum usually distinctly convex, not flattened; habitus as in Fig. 6; distribution from Mexico through much of South America................................ ................................................................................................................... Caraguata Bechyné, 1954
27. Basal margin of pronotum very strongly bisinuate from meson to posterolateral pronotal angle (Fig. 188); posterolateral angle positioned far anterior to most posterior part of pronotum; elytra uniformly dark; habitus as in Fig. 40; distribution from Arizona to Costa Rica ........................................................................... Ophraea Jacoby, 1886 [in part; see couplet 15]
– Basal margin of pronotum usually not strongly bisinuate as described above; if basal margin of pronotum strongly bisinuate, then elytra partly or entirely pale...................................................... 28
28. Third and fourth antennomeres nearly equal in length; each elytron yellow, with long, broad, sublateral, black vitta extending from base, over humerus, to shortly before elytral apex; most specimens also with short, black, basal vitta positioned midway between scutellum and sublateral vitta; yellow areas of elytra with greenish tint in some specimens; habitus as in Fig. 24; Palearctic species, adventive in North and South America.......................... Xanthogaleruca Laboissière, 1934
– Third and fourth antennomeres differing in length; if third and fourth antennomere lengths only slightly different, then elytral color pattern not as above ................................................................ 29
29. Third antennomere shorter than fourth ............................................................................................ 30
– Third antennomere longer than fourth, in some species only slightly so ........................................ 33
30. Pronotum short and broad, at least 2.5 times as wide as long ......................................................... 31
– Pronotum less than 2.5 times as wide as long ................................................................................. 32
31. Depression on each side of pronotum large, extending to anterolateral and posterolateral corners of pronotum (Fig. 192); due to large depressions, pronotum broadly explanate laterally; habitus as in Fig. 14; distribution from Guatemala to Panama ............................................. Megarhabda gen. nov.
– Lateral depressions of pronotum smaller, not extending to anterolateral and posterolateral corners; pronotum more evenly convex; habitus as in Fig. 12; distribution from Canada to Mexico .......................................................................................................... Derospidea Blake, 1931
32. Elytral surface rough, but punctation usually not visible without magnification; elytra vittate in many species, but varying from entirely pale to entirely dark; aedeagus with dorsal, thinly chitinized groove extending medially for most of aedeagal length; body 4–12 mm long; habitus as in Fig. 15; distribution from Canada to Guatemala ............... Trirhabda LeConte, 1865 [in part; see couplet 58]
– Elytral punctation of some species coarser, noticeable without magnification; elytra not vittate; aedeagus lacking dorsal groove as described above; body 7–14 mm long; habitus as in Fig. 19; distribution in Mexico and Guatemala (doubtfully reported from Brazil) ........ Nestinus Clark, 1865
33. Both male and female with antennomeres 7–11 strongly broadened and flattened, with each antennomere shorter than wide (Fig. 208); elytra with callosities near mid-length (Fig. 229); habitus as in Fig. 33; distribution in South America ......................................... Platynocera Blanchard, 1842
– Antennomeres 7–10, whether or not short, not strongly broadened and flattened in either sex; elytra without callosities near mid-length.................................................................................................. 34
34. Body length 10.0 mm or more......................................................................................................... 35
– Body length 8.0 mm or less ............................................................................................................. 39
35. Third antennomere equal to or longer than fourth to sixth antennomeres combined; fifth to ninth antennomeres short, each not more than twice as long as wide; habitus as in Fig. 7; distribution from Guatemala through much of South America ........................................... Coelomera Chevrolat, 1836
– Third antennomere shorter than fourth to sixth antennomeres combined; fifth to ninth antennomeres more elongate................................................................................................................................... 36
36. Pronotum distinctly broader in distal half than in basal half, with lateral margins strongly sinuate (Fig. 186); third antennomere distinctly longer than fourth antennomere, more than three times as long as second antennomere; habitus as in Fig. 10; distribution in South America....................................................................... Dircema Clark, 1865 [in part; see couplet 51]
– Pronotum not distinctly broader in distal half, without strongly sinuate lateral margins; third antennomere as above or not ........................................................................................................... 37
37. Epipleuron more than twice as wide as second antennomere length, wider than apical portion of foretibia; elytra broadly explanate in dorsal view; habitus as in Fig. 2; distribution in Central America and northwestern South America ............................................ Platycesta Viswajyothi & Clark, 2021
– Epipleuron not more than two times as wide as second antennomere length, not distinctly wider than apical portion of foretibia; elytra narrowly explanate in dorsal view.............................................. 38
38. Pronotum at least twice as wide as long; lateral carina of pronotum well developed, narrowly explanate; habitus as in Fig. 1; distribution from United States through much of South America, and in West Indies........................................................... Monocesta Clark, 1865 [in part; see couplet 54]
– Pronotum less than twice as wide as long; lateral pronotal carina weakly developed, especially anteriorly; habitus as in Figs 4–5; distribution from Texas to Guatemala ............ Coraia Clark, 1865
39. Elytral pubescence nearly absent, but usually noticeable laterally; weak carina present behind humerus, extending most of elytral length (Fig. 220); habitus as in Fig. 20; Palearctic species, introduced to North America (United States and Mexico) ............................ Diorhabda Weise, 1883
– Elytral pubescence dense in most species; if elytral pubescence nearly absent, then elytra not carinate............................................................................................................................................. 40
40. Elytra pale brown, in most species with darker speckles, which often coalesce to form irregular blotches; elytral vittae, if present, usually short and irregular; antennae short, not or barely reaching beyond base of elytra; abdomen of male with deflexed pygidium in most cases............................ 41
– Elytral coloration varying from entirely pale to entirely black; dark elytral markings not forming speckles or irregular blotches, sometimes forming long, regular vittae; antennae usually longer, distinctly extending beyond humeri; abdomen without deflexed pygidium.................................... 42
41. Lateral third of pronotum almost entirely occupied by large depression; prothorax usually more than twice as wide as long; gender either male or female; habitus as in Fig. 36; distribution from Canada to Mexico ......................................................................................................... Yingabruxia gen. nov.
– Lateral third of pronotum partially occupied by convex elevation; pronotum usually not distinctly more than twice as wide as long; gender usually male (female claws simple, except in one anomalous species with bifid claws); habitus as in Fig. 35; distribution from Canada to Guatemala .............................................................. Monoxia LeConte, 1865 [in part; see couplet 12]
42. Front coxae narrowly but distinctly separated from each other by posterior extension of prosternum; middle coxae separated from each other by distance subequal to half coxal width (Fig. 153); pronotum polished and nearly impunctate, except in depressions; all tibiae lacking apical spurs in both male and female; habitus as in Fig. 25; distribution in Canada and United States ......................................................... Galerucella Crotch, 1873 (subgenus Galerucella Crotch)
– Front coxae not separated by prosternum; middle coxae closely approximate but rarely in actual contact (Fig. 154); male with broad, often curved, apical spur on middle tibia.............................. 43
43. Elytra with distinct, dark vittae (Figs 37–38); distribution from Canada to Mexico ...................................................... Ophraella Wilcox, 1965 [in part; see couplets 46, 55, 66]
– Elytra not distinctly vittate............................................................................................................... 44
44. Fourth antennomere distinctly longer than second; outer margin of epipleuron (marginal bead between disc of elytron and epipleuron) sometimes becoming obscure near apex, but inner margin (next to body) always distinct to apex or to point where it joins outer margin ............................... 45
– Second and fourth antennomeres nearly equal in length; inner margin of epipleuron remaining distant from outer margin, ending rather abruptly before apex; distribution in Canada and United States .................................................... Galerucella Crotch, 1873 (subgenus Neogalerucella Chûjô)
45. Elytral punctures relatively fine, similar in size to those of abdomen; pronotum pale with three dark markings, one mesal and one at each side lateral to depressed area; habitus as in Fig. 23; Palearctic species, adventive in Canada and United States ............................................ Pyrrhalta Joannis, 1865
– Elytral punctures much larger than those of abdomen; dark pronotal markings sometimes present on sublateral tubercles or in sublateral depressions, but not lateral to depressions.............................. 46
46. Median lobe of aedeagus symmetrical; aedeagal orifice located very near aedeagal apex, small, without weakly sclerotized area above it; body oval, usually (but not always) strongly convex; hosts Asteraceae; habitus as in Fig. 39; distribution from Canada to Mexico ...................................................... Ophraella Wilcox, 1965 [in part; see couplets 43, 55, 66]
– Median lobe of aedeagus strongly asymmetrical, with apex curved to one side; aedeagal orifice large, with weakly sclerotized area above it; body usually more oblong, not as convex; hosts other than Asteraceae; habitus as in Fig. 22; distribution in Canada and United States ..................................................... Tricholochmaea Laboissière, 1932 [in part; see couplet 23]
47. Pronotal punctation very coarse, with punctures distinctly larger than those of elytra; upon close examination, elytra with numerous, short, appressed setae (easily rubbed off in some specimens); aedeagus extraordinary long, C-shaped, forming complete semicircle in lateral view; tarsal claws bifid in male, simple in female; procoxal cavities open behind; habitus as in Fig. 34; distribution from Canada to Argentina .............................. Erynephala Blake, 1936 [in part; see couplets 12, 15]
– Pronotal punctation coarse to fine; if coarse, then tarsal claws appendiculate or procoxal cavities closed behind; aedeagus not exceptionally long and C-shaped....................................................... 48
48. Tarsal claws bifid; inner appendage of claw sharply pointed at apex.............................................. 49
– Tarsal claws appendiculate; inner appendage of claw broad and apically blunt ............................. 95
49. Elytra short, leaving much of abdomen uncovered; portion of mesosternum anterior to mesocoxa shorter than anterior to posterior length of mesocoxa; mesosternum with anteromesal tubercle; habitus as in Fig. 50; distribution in Ecuador and Peru ..................................... Metalepta Baly, 1861
– Elytra and mesosternum not both as above ..................................................................................... 50
50. Procoxal cavities closed behind (Fig. 150); elytral disc usually with several longitudinal costae; habitus as in Fig. 44; distribution in Canada and United States .................. Galeruca Geoffroy, 1762
– Procoxal cavities open behind (Figs 151–152); elytral disc either with or without costae ............. 51
51. Pronotum distinctly broader in distal half than in basal half, with lateral margins strongly sinuate (Fig. 186); third antennomere distinctly longer than fourth antennomere, more than three times as long as second antennomere; habitus as in Fig. 10; distribution in South America....................................................................... Dircema Clark, 1865 [in part; see couplet 36]
– If pronotum distinctly broader in distal half than in basal half, then antennae not as above........... 52
52. Entire anterior pronotal margin with well-formed fringe of short, densely spaced setae................ 53
– Setal fringe absent from anterior pronotal margin, or noticeable only laterally.............................. 59
53. Elytra with numerous erect setae arranged in rows (Figs 77–78); distribution from Canada through much of South America, as well as in West Indies.............................................................................. ............................................................................... Acalymma Barber, 1947 [in part; see couplet 94]
– Elytral setae either absent or short and appressed ........................................................................... 54
54. Extensor margin of tibiae deeply channeled, with distinct carina between margins of channel, therefore tricarinate; habitus as in Fig. 1; distribution from United States through much of South America, and in West Indies.................................... Monocesta Clark, 1865 [in part; see couplet 38]
– Tibiae not deeply grooved and tricarinate ....................................................................................... 55
55. Third antennomere longer than fourth; habitus as in Figs 37–39; distribution from Canada to Mexico ...................................................... Ophraella Wilcox, 1965 [in part; see couplets 43, 46, 66]
– Third antennomere shorter than fourth ............................................................................................ 56
56. Tibiae with easily visible apical spurs; habitus as in Fig. 124; distribution in United States and Mexico ..................................................................... Triarius Jacoby, 1887 [in part; see couplet 140]
– Tibial spurs either absent or tiny and hidden among nearby setae .................................................. 57
57. Third antennomere not more than 1.5 times as long as second antennomere; habitus as in Fig. 67; distribution from Canada through much of South America, as well as in West Indies ....................... ....................................................... Diabrotica Chevrolat, 1836 [in part; see couplets 78, 80, 81, 82]
– Third antennomere more than 1.5 times as long as second antennomere ....................................... 58
58. Both anterior and posterior margins of pronotum with fine bead; elytra, upon close inspection, with numerous appressed setae; apex of male abdomen arcuately incised; habitus as in Fig. 15; distribution from Canada to Guatemala ............... Trirhabda LeConte, 1865 [in part; see couplet 32]
– Both anterior and posterior margins of pronotum lacking marginal bead; elytra with a few erect setae, especially towards apex, but without appressed setae; apex of male abdomen with rectangular lobe; habitus as in Fig. 127; distribution from United States to Panama ........................................................... Scelida Chapuis, 1875 [in part; see couplets 152, 184]
59. Elytra strongly tuberculate; pronotum and elytra coarsely punctate ............................................... 60
– If elytra strongly tuberculate, then pronotum and elytra not both coarsely punctate ...................... 61
60. Body less than twice as long as broad (Figs 29–30); distribution from Mexico through much of South America, as well as in West Indies .......... Yingaresca Bechyné, 1956 [in part; see couplet 19]
– Body more than twice as long as broad; habitus as in Fig. 13; distribution in Cuba and Hispaniola ............................................................................................ Dicoelotrachelus Blake, 1941
61. Both male and female with third, fourth, and fifth antennomeres elongate, subequal in length, each distinctly longer than sixth antennomere (1.5 or more times longer); mesotibia in many males with emargination on flexor margin, modified into clasping organ (Fig. 205); mesofemur of some species expanded apically; habitus as in Fig. 91; distribution in Panama and northern South America.................................................................................................. Aristobrotica Bechyné, 1956
– Third, fourth, and fifth antennomeres not all significantly elongate in comparison to sixth antennomere; in most genera, preapical emargination of male mesotibiae absent; if male with preapical tibial emargination, then tibia not modified to form clasping organ......................................................... 62
62. Genal distance (distance from eye margin to external edge of mouth, before base of mandible) large, equal to at least half maximum diameter of eye (Fig. 180); eye small, with maximum diameter not more than three-fourths interocular distance, usually two-thirds or less......................................... 63
– Genal distance small, less than half-maximum diameter of eye (Figs 181–182); eyes small to large ................................................................................................................................................ 70
63. Antenna inserted at or below middle level of eyes; face flat, not excavated; ventral surface of proximal three tarsomeres of male front leg uniformly covered with truncate setae, forming adhesive patch ................................................................................................................................................ 64
– Antenna inserted above midline of eyes (sometimes at midline in female), widely separated from eyes (space between antennal fossa and eye equal to half diameter of antennal fossa); proximal three tarsomeres of male foreleg densely setose ventrally, but without patch of truncate adhesive setae; males of most species with face excavated (Figs 158–160); habitus as in Fig. 82; distribution from Mexico through much of South America........................................ Gynandrobrotica Bechyné, 1955
64. Distal male antennomeres not distinctly enlarged ........................................................................... 65
– One or more antennomeres in distal half of male antenna distinctly broadened............................. 68
65. Male with front femora much wider than hind femora; front trochanter of male posteriorly produced to form spine-like process (Figs 180, 207); elytral disc with longitudinal rows of erect setae (easily abraded); lateral pronotal margin with regular row of short setae (easily abraded); habitus as in Fig. 90; distribution in Ecuador ......................................... Prathapanius Viswajyothi & Clark, 2020
– Male with front femora narrower than hind femora; front trochanter of male without posterior process; elytral disc and pronotal margin either with or without such setae ................................... 66
66. Genal length more than greatest diameter of eye; aedeagus with basal spurs; habitus as in Figs 37– 39; distribution in Canada and United States ...................................................................................... .................................................................. Ophraella Wilcox, 1965 [in part; see couplets 43, 46, 55]
– Genal length less than greatest diameter of eye; aedeagus lacking basal spurs; distribution in Latin America............................................................................................................................................ 67
67. Elytra with numerous, long, erect setae; male mesotibia with preapical, ventral notch; habitus as in Fig. 109; distribution in northern South America................................................................................ ....................................................... Parabrotica Bechyné & Bechyné, 1961 [in part; see couplet 74]
– Elytra nearly asetose; male mesotibia lacking preapical notch; habitus as in Figs 84– 88; distribution from Mexico through much of South America, as well as in West Indies........................................................................ Isotes Weise, 1922 [in part; see couplets 86, 92]
68. Third antennomere distinctly longer than fourth (Fig. 209); mesotibiae of male with broad, shallow, subapical emargination; habitus as in Fig. 81; distribution in Venezuela and Brazil .................................................................................. Cornubrotica Bechyné & Bechyné, 1969
– Third antennomere subequal to or shorter than fourth; mesotibiae in male not emarginate, although bent at apical third in some specimens ............................................................................................ 69
69. Seventh and especially ninth antennomeres of male much wider than other antennomeres and somewhat pointed laterally; elytra metallic green or blue, with yellow lateral and distal areas; elytral punctation dense, with punctures separated by distance less than their diameters; habitus as in Fig. 83; distribution in South America ...... Buckibrotica Bechyné & Bechyné, 1969 [in part; see couplet 88]
– Eighth through eleventh male antennomeres enlarged, with tenth antennomere largest, although with ninth antennomere nearly as large in some species; elytral color and punctation not as above; habitus as in Fig. 79; distribution in South America ................................................. Ensiforma Jacoby, 1876
70. Lateral margin of prothorax with large setae only on anterior and posterior angles or with only one or two small setae placed near large setae..............................................71 [Note that the setae along the lateral margin are easily rubbed off or are difficult to see at lower magnifications. If a specimen, apparently without lateral prothoracic setae, is not identifiable using the key, the user should return to this part of the key and attempt identification as if the specimen had lateral pronotal setae.]
– Lateral margin of prothorax with six or more fine, evenly spaced setae......................................... 90
71. Upon close examination, lateral portion of anterior pronotal margin with fringe of short setae; terminal maxillary palpomere short, stout, abruptly narrowed to nipple-like apex (Fig. 157); habitus as in Fig. 59; distribution in South America ......................................................... Byblitea Baly, 1864
– Anterior pronotal margin lacking setal fringe; terminal maxillary palpomere of many genera slender.............................................................................................................................................. 72
72. Genal distance (distance from eye margin to external edge of mouth, before base of mandible) small, less than one-fourth maximum diameter of eye (Fig. 182) ............................................................. 73
– Genal distance medium sized, one-fourth to one-half maximum diameter of eye (Fig. 181)......... 83
73. Third antennomere 2.5–3.5 times as long as second antennomere.................................................. 74
– Third antennomere not more than 1.5 times as long as second antennomere ................................. 77
74. Elytra with numerous erect setae; male mesotibia with preapical notch; habitus as in Fig. 109; distribution in northern South America ............................................................................................... ....................................................... Parabrotica Bechyné & Bechyné, 1961 [in part; see couplet 67]
– Elytra lacking numerous erect setae; male mesotibia with or without preapical emargination ...... 75
75. Mesotibia emarginate before apex; distribution in Peru and Bolivia .......... Palmaria Bechyné, 1956
– Mesotibia not emarginate before apex............................................................................................. 76
76. Inner lobe of tarsal claw only about half as long as outer lobe; gender male (female with appendiculate tarsal claws); habitus as in Fig. 92; distribution in northern South America...................................... Hyperbrotica Bechyné & Bechyné, 1968 [in part; see couplet 121]
– Inner lobe of tarsal claw three-fourths or more times as long as outer lobe; gender either male or female; habitus as in Figs 70–71; distribution from United States through much of South America, as well as in West Indies...................... Paranapiacaba Bechyné, 1958 [in part; see couplets 88, 92]
77. Third antennomere, at least in males, slightly shorter than second antennomere, together usually considerably shorter than fourth antennomere ................................................................................ 78
– Third antennomere equal to or slightly longer than second antennomere, together more than half as long as fourth antennomere ............................................................................................................. 79
78. Fourth antennomere about as long as first, second, and third antennomeres combined (Fig. 231); male with ninth antennomere, and sometimes others also, greatly enlarged (Fig. 217); middle tibia of male with distinct, preapical, ventral notch; habitus as in Fig. 113; distribution from Costa Rica to Bolivia .................................................................................................... Deinocladus Blake, 1966
– Fourth antennomere much shorter than first, second, and third antennomeres combined; antennae filiform; male middle tibia without preapical notch; distribution in Central and South America................... Diabrotica Chevrolat, 1836 [in part (signifera group); see couplets 57, 80–82]
79. Metepisternum and adjacent metasternum with patch of long, silky, golden or silvery, overlapping setae (Fig. 230) ................................................................................................................................ 80
– Metepisternum without golden or silvery setae............................................................................... 81
80. Elytron with two transverse depressions on disc, one behind basal callus, one behind mid-length; distribution Central America.......... Diabrotica Chevrolat, 1836 [in part; see couplets 57, 78, 81–82]
– Elytron without two transverse depressions; pronotum as in Fig. 190; habitus as in Fig. 66; distribution in South America ................................................................................... Cochabamba Bechyné, 1955
81. Elytral surface even, not longitudinally sulcate, although sometimes with one or two short plicae in posthumeral area.............................................................................................................................. 82
– Each elytron with two or more distinct, sinuate, longitudinal sulci, strongest behind humeral callus, extending beyond middle; pronotum deeply bifoveate; distribution from Canada through much of South America ... Diabrotica Chevrolat, 1836 [in part (virgifera group); see couplets 57, 78, 80, 82]
82. Sixth to tenth antennomeres of male enlarged and ventrally excavated; distribution in Argentina ................................................................................... Platybrotica Cabrera & Walsh, 2004
– Male antennae not as above; habitus as in Fig. 67; distribution from Canada through much of South America, as well as in West Indies ...................................................................................................... ....................................................... Diabrotica Chevrolat, 1836 [in part; see couplets 57, 78, 80–81]
83. Head, pronotum, and abdomen strongly alutaceous, black with distinct blue or green luster; legs and antennae dark brown; apical portion of male elytron attenuate and deeply excavated, with dense setae along sutural rim of excavation; habitus as in Fig. 72; distribution in Panama ...................................................................................................... Microbrotica Jacoby, 1887
– Not as above .................................................................................................................................... 84
84. Pronotum at mid-length with transverse impression occupying most of pronotal width; body less than 5 mm long; elytral punctation of most (but not all) species rather coarse, with punctures separated from each other by distance about equal to diameter of puncture; habitus as in Fig. 18; distribution from United States to South America, as well as in West Indies...................... Miraces Jacoby, 1888
– If pronotum with transverse impression, then body more than 5 mm long..................................... 85
85. Third antennomere 1.5 or more times as long as second antennomere........................................... 86
– Second and third antennomeres subequal in length; head and pronotum with pattern of spots; pronotum strongly foveate (Fig. 191); habitus as in Fig. 74; distribution from Brazil to Argentina ............................................................................ Anisobrotica Bechyné & Bechyné, 1969
86. Basal tarsomere of hind leg long, in male longer than two following tarsomeres combined.......... 87
– Basal tarsomere of hind leg short, in male subequal to two following tarsomeres combined; habitus as in Figs 84–88; distribution from Mexico through much of South America, as well as in West Indies........................................................................ Isotes Weise, 1922 [in part; see couplets 67, 92]
87. Elytra in male often dilated posteriorly, but without raised areas, excavations, or depressions...... 88
– Elytra in male with raised areas, excavations, or depressions in posterior half .............................. 89
88. Seventh and especially ninth antennomeres of male much wider than other antennomeres and somewhat pointed laterally; elytra metallic green or blue, with yellow lateral and distal areas; elytral punctation dense, with punctures separated by distance less than their diameters; habitus as in Fig. 83; distribution in South America ...... Buckibrotica Bechyné & Bechyné, 1969 [in part; see couplet 69]
– Not as above; habitus as in Figs 71–72; distribution from United States through much of South America, as well as in West Indies ...... Paranapiacaba Bechyné, 1958 [in part; see couplets 76, 92]
89. Distal portion of male elytron not excavated, or (if excavated) excavation not extending to elytral apex (Fig. 227); habitus as in Figs 75–76; distribution from United States through much of South America.................................................................................................. Paratriarius Schaeffer, 1906
– Male elytron narrowed sharply in distal fourth to form point, with apex excavated (Fig. 228); habitus as in Fig. 80; distribution in Mexico .................................................. Pseudodiabrotica Jacoby, 1892
90. Elytra largely asetose, irregularly punctate, sometimes with scattered setae in apical third or on margins............................................................................................................................................. 91
– Elytral disc with erect or suberect setae, often arranged in rows .................................................... 93
91. Elytra without vittae ........................................................................................................................ 92
– Elytra vittate; maximum diameter of eye equaling two-thirds to three-fourths interocular distance; habitus as in Fig. 73; distribution from United States to northern South America ............................. .................................................................................................................. Amphelasma Barber, 1947
92. Elytra faintly striate; habitus as in Figs 70–71; distribution from United States through much of South America, as well as in West Indies ...... Paranapiacaba Bechyné, 1958 [in part; see couplets 76, 88]
– Elytra without striae; habitus as in Figs 84–88; distribution from Mexico through much of South America, as well as in West Indies.......................... Isotes Weise, 1922 [in part; see couplets 67, 86]
93. Elytra with erect or suberect setae scattered on disc, not arranged in rows; habitus as in Fig. 68; distribution in Peru, Bolivia, and Brazil .................................................... Zischkaita Bechyné, 1956
– Elytra with erect or suberect setae arranged in rows ....................................................................... 94
94. Apex of abdomen deeply incised; gender male (females with appendiculate claws); habitus as in Fig. 89; distribution in Costa Rica and Panama ................................................................................. .................................................... Heterochele Viswajyothi & Clark, 2021 [in part; see couplet 133]
– Apex of male abdomen not deeply incised; gender either male or female; habitus as in Figs 77–78; distribution from Canada through much of South America, as well as in West Indies...................................................................... Acalymma Barber, 1947 [in part; see couplet 53]
95. Terminal ventrite of male abdomen with large, nearly square, apical lobe; aedeagal orifice with sclerotized covering; hind leg with basitarsus usually (but not always) longer than tarsomeres 2–5 combined; tibiae with apical spurs conspicuous, much longer than nearby setae........................... 96
– Apical lobe of male abdomen either absent or much wider than long; aedeagal orifice of most species lacking sclerotized covering; hind leg with basitarsus usually (but not always) shorter than tarsomeres 2–5 combined; tibial spurs often (but not always) only slightly longer than nearby setae, often more or less hidden among nearby setae, sometimes absent................................................ 103
96. Front coxal cavities closed behind (Fig. 150).................................................................................. 97
– Front coxal cavities open behind (Fig. 151) .................................................................................... 98
97. New World species usually testaceous, orange, or yellow (brown to black in a few species); dark elytral markings usually faint, irregular, or absent; many species with dark markings on pronotum; body usually elongate oval; dorsum usually less convex than in Monolepta; habitus as in Fig. 139; reported distribution from United States through Peru ........................................................................ ........................................................................ Metrioidea Fairmaire, 1882 [in part; see couplet 100]
– Color various, but usually not as described above; dorsum usually more convex than in Metrioidea; habitus as in Fig. 142; reported distribution from Mexico to Panama .... Monolepta Chevrolat, 1836
98. Hind leg with basal tarsomere shorter than or equal to all following tarsomeres combined........... 99
– Hind leg with basal tarsomere longer than all following tarsomeres combined............................ 100
99. Dorsum somewhat flattened; habitus as in Fig. 140; distribution in South America .......................... ..................................................................................................................... Halinella Bechyné, 1956
– Dorsum more convex; habitus as in Fig. 138; distribution in United States and Mexico ................... ...................................................................... Eusattodera Schaeffer, 1906 [in part; see couplet 101]
100. New World species usually testaceous, orange, or yellow (brown to black in a few species); dark elytral markings usually faint, irregular, or absent; many species with dark markings on pronotum; body usually elongate oval, dorsally convex; habitus as in Fig. 139; reported distribution from United States through Peru ............................. Metrioidea Fairmaire, 1882 [in part; see couplet 97]
– Color often otherwise; distribution from United States through much of South America .......... 101
101. Body of most species rather elongate; elytra entirely black, sometimes with blue luster; habitus as in Fig. 138; distribution in United States and Mexico ....................................................................... ...................................................................... Eusattodera Schaeffer, 1906 [in part; see couplet 99]
– Body of most species less elongate, with dorsum more convex; elytral color of some species entirely black, but of many species otherwise; distribution south of United States .................... 102
102. Reported distribution in South America; habitus as in Fig. 143 ............... Lilophaea Bechyné, 1958
– Reported distribution from United States through much of South America; habitus as in Fig. 141. ........................................................................................................... Luperodes Motschulsky, 1858
103. Pronotum lacking lateral carina (Figs 193–194) ......................................................................... 104
– Lateral margin of pronotum carinate ........................................................................................... 105
104. Elytra black with suture and lateral margins pale, without transverse band near mid-length; antennae of male and female filiform, unmodified; head of male with small, median, round hole distal to antennal insertions (Fig. 164); habitus as in Fig. 102; distribution in Texas and Mexico .................................................................................................... Cyclotrypema Blake, 1966
– Elytral color pattern including transverse, pale band near mid-length; male with second and third antennomeres strongly modified (Fig. 212); head lacking small hole distal to antennal insertions (Figs 162–163); habitus as in Fig. 94; distribution in South America............................................... ............................................................................................................ Metrobrotica Bechyné, 1958
105. Front coxal cavities closed behind............................................................................................... 106
– Front coxal cavities open behind..................................................................................................110
106. Antennae filiform, with third antennomere equal to or shorter than fourth................................. 107
– Third antennomere longer than fourth; antennae either entirely filiform or with some antennomeres greatly modified ........................................................................................................................... 108
107. Elytral punctures confused; middle tibia of male with preapical, ventral notch; pronotum with pore, as illustrated in Fig. 179; habitus as in Fig. 114; distribution in Brazil ............................................. .............................................................................................................. Coronabrotica Moura, 2010
– Elytral punctures arranged in irregular rows; middle tibia of male lacking preapical notch; pronotum without such pore; habitus as in Fig. 98; distribution in Venezuela and Brazil ...................................................................................................... Potamobrotica Blake, 1966
108. Third and fourth antennomeres greatly enlarged and modified (Fig. 210); area below antennal insertions deeply excavated (Figs 165–166); gender male; habitus as in Fig. 97; distribution from Canada through much of South America, as well as in West Indies.............................................................. Cerotoma Chevrolat, 1836 [in part; see couplet 109]
– Third and fourth antennomeres unmodified; area below antennal insertions sometimes depressed, but not deeply excavated; gender either male or female ............................................................. 109
109. Female with area just anterior to antennal insertions shallowly, transversely depressed; body more elongate oval than in Cerotoma; distribution in Brazil ...... Interbrotica Bechyné & Bechyné, 1965
– Female without transverse impression just anterior to antennal insertions; body less elongate; habitus as in Fig. 97; distribution from Canada through much of South America, as well as in West Indies.............................................................. Cerotoma Chevrolat, 1836 [in part; see couplet 108]
110. Mesepisternum densely pubescent; anterior margin of prothorax without bead and without fringe of short setae; male without rectangular lobe at abdominal apex; males of some genera with preapical notch on flexor side of middle tibia; aedeagus without basal spurs .............................................111
– Mesepisternum asetose or sparsely pubescent; if mesepisternum sparsely pubescent, then anterior pronotal margin usually with bead or fringe of short setae; abdominal apex with or without rectangular lobe; middle tibia without preapical notch, except in some species with numerous erect elytral setae; aedeagus with or without basal spurs ..................................................................... 131
111. Hind femur greatly swollen, as in many genera of tribe Alticini; middle tibia of male with preapical notch on flexor side (Fig. 202); color yellow, with head and two spots on each elytron dark; habitus as in Fig. 108; distribution in Cuba ......................................................... Leptonesiotes Blake, 1958
– Hind femur not abnormally swollen; male middle tibia with or without preapical notch; color usually otherwise ..........................................................................................................................112
112. Posterior margin of pronotum with complete, uninterrupted bead; male with eighth or ninth antennomere distinctly enlarged (Fig. 214); other male antennomeres also enlarged in some species; female of most species also with some antennomeres enlarged, but not as much as in males; middle tibia of male without preapical notch; elytra entirely dark; pronotum usually pale; if pronotum dark, then both front and middle legs of male with basal tarsomeres greatly enlarged; habitus as in Fig. 126; distribution in Mexico and Central America ..................................................................... ......................................................................... Metacoryna Jacoby, 1888 [in part; see couplet 131]
– Posterior margin of pronotum often with poorly formed bead in lateral portion, but usually without well-formed, uninterrupted bead; male antennae of some species modified, with some antennomeres enlarged, but usually not as above; female antennae of all species filiform, without enlarged antennomeres; middle tibia of male with or without preapical notch; color often different than described above.....................................................................................................................113
113. Pronotal disc convex, not at all impressed; habitus as in Fig. 104; distribution in West Indies........ ................................................................................................................... Ectmesopus Blake, 1940
– Pronotal disc distinctly impressed in most species; distribution in continental areas, not including West Indies....................................................................................................................................114
114. Eye very small, with diameter less than distance from eye margin to mandibular base; third male antennomere much widened and irregularly incised at middle; male with head deeply excavated beyond antennal insertions; elytra vittate; habitus as in Fig. 95; distribution in Mexico .................. ................................................................................................................ Rachicephala Blake, 1966
– Eye usually larger; if third male antennomere enlarged, then not incised, or incised only apically; male head excavated or not; elytra vittate or not..........................................................................115
115. Elytral disc with numerous, longitudinal costae...........................................................................116
– Elytra not distinctly costate, except sometimes behind humeri................................................... 120
116. Elytral costae moderately to strongly developed; male head of some species deeply excavated beyond antennal insertions ...........................................................................................................117
– Elytral costae weakly developed; head not excavated..................................................................119
117. Frons similar in both sexes, slightly depressed, with mesal carina indistinct; habitus as in Fig. 93; distribution in South America....................................................................... Hystiopsis Blake, 1966
– Frons deeply excavated in male, unmodified in female (Figs 167–171)......................................118
118. Elytral costae strong; transverse pronotal impression very deep; third antennomere of female equal to or shorter than fourth, never longer; habitus as in Fig. 99; distribution in South America............................................................................................. Eucerotoma Laboissière, 1939
– Elytral costae moderate; pronotal impression more shallow (as in Neobrotica); third antennomere of female equal to or longer than fourth, never shorter (Fig. 211); habitus as in Fig. 101; distribution from Mexico through much of South America........................................... Eccoptopsis Blake, 1966
119. Third antennomere less than twice as long as second; middle tibia of male with deep, preapical notch; habitus as in Fig. 111; distribution from United States through much of South America........................................................... Luperosoma Jacoby, 1891 [in part; see couplet 130]
– Third antennomere more than twice as long as second; middle tibia of male without preapical notch; habitus as in Fig. 96; distribution from United States through much of South America............................................................. Neobrotica Jacoby, 1887 [in part; see couplet 122]
120. Male tibia without preapical notch; antennae eleven-segmented, with third antennomere nearly as long as fourth............................................................................................................................... 121
– Male tibia with preapical notch; most species with third antennomere much shorter than fourth (if antenna with fewer than eleven antennomeres, then second or third antennomere entirely missing); if third and fourth antennomeres similar in length, then elytra with exceptionally coarse punctation .................................................................................................................................... 123
121. Each elytron pale brown, with 5–6 elongate maculae, one extending posteriorly from humerus to beyond middle of elytron (sometimes divided to form two smaller maculae), two near suture in basal half (one behind the other), two near distal declivity(one near suture, the other slightly more posterior, near apicolateral angle); gender female (males with bifid claws); habitus as in Fig. 92; distribution in northern South America......... Hyperbrotica Bechyné & Bechyné, 1968 [in part; see couplet 76]
– Elytral color pattern not as above; gender either male or female ................................................ 122
122. Male with mesal spine or spine-like tuft of setae on clypeus (Fig. 176); male protibiae greatly enlarged (Figs 176–177); habitus as in Fig. 106; distribution from Mexico to Panama ........................................................... Platymorpha Jacoby, 1888 [in part; see couplet 127]
– Male without such clypeal spine, without enlarged front tibiae; habitus as in Fig. 96; distribution from United States through much of South America ........................................................................ ........................................................................... Neobrotica Jacoby, 1887 [in part; see couplet 119]
123. Male antenna with fewer than eleven antennomeres (female with eleven); if distribution south of United States, then frons unusually flat or broadly concave, without mesal carina; regardless of distribution, metasternum yellow ................................................................................................ 124
– Antenna of both male and female with eleven antennomeres; frons of most species not flat or concave, usually bulging or with mesal elevation; if distribution in United States then metasternum dark brown or black ..................................................................................................................... 125
124. Male antennae with some antennomeres towards base distinctly distorted (Fig. 216); frons, especially of male, rather flat or broadly concave, without distinct mesal elevation (Fig. 172); habitus as in Fig. 105; distribution from Mexico to South America ............... Oroetes Jacoby, 1888
– Male antennae not modified; frons mesally elevated; habitus as in Fig. 100; distribution in eastern United States ............................................................................................ Phyllecthris Dejean, 1836
125. Frons convex, bulging, without mesal ridge; male with mesal pore on frons, slightly beyond level of antennae (Fig. 173); habitus as in Fig. 103; distribution from Panama to Peru and Brazil .......................................................................................................... Porechontes Blake, 1966
– Frons not bulging, without mesal pore, usually with mesal ridge............................................... 126
126. Male with fifth to seventh antennomeres slightly enlarged; head black; pronotum pale; each elytron pale with two dark markings on distal declivity, with one elongate dark marking on scutellum and postscutellar area, with one elongate dark marking in subscutellar area (sometimes united with humeral marking); distribution in Brazil ........................................................ Simopsis Blake, 1966
– Male antennomeres either enlarged or not; color pattern not as above ....................................... 127
127. Elytra uniformly dark, with metallic luster, coarsely punctate, with punctures separated from each other by distance less than diameter of puncture; habitus as in Fig. 107; distribution in Central America........................................................................................................ Trachyelytron gen. nov.
– Elytra not as above....................................................................................................................... 128
128. Proximal tarsomere of hind leg very long, clearly longer than all more distal tarsomeres combined; elytra somewhat depressed beyond middle; distribution in Colombia and Brazil ........................... .................................................................................................................. Romanita Bechyné, 1957
– Proximal tarsomere of hind leg at most slightly longer than more distal tarsomeres combined; elytra usually not depressed beyond middle................................................................................ 129
129. Male with mesal spine or spine-like tuft of setae on clypeus (Fig. 177); male foretibiae greatly enlarged (Figs 176–177); habitus as in Fig. 106; distribution from Mexico to Panama ........................................................... Platymorpha Jacoby, 1888 [in part; see couplet 122]
– Male without such clypeal spine, without enlarged front tibiae.................................................. 130
130. Distal half of male antenna with some antennomeres distinctly broadened; habitus as in Fig. 111; distribution from United States through much of South America........................................................... Luperosoma Jacoby, 1891 [in part; see couplet 119]
– Distal half of male antenna with all antennomeres narrow; habitus as in Fig. 110; distribution from Mexico through much of South America........................................................................................... ................................................................... Trichobrotica Bechyné, 1956 [in part; see couplet 133]
131. Male with some of fifth through tenth antennomeres greatly enlarged; second, third, fourth, and eleventh male antennomeres narrow (Fig. 214); female of most species also with some antennomeres enlarged, but not as much as in males; elytra entirely dark; pronotum usually pale; if pronotum dark, then both front and middle tarsi of male greatly enlarged; habitus as in Fig. 126; distribution in Mexico and Central America....................... Metacoryna Jacoby, 1888 [in part; see couplet 112]
– Male usually with all antennomeres (except first) narrow, less often with some antennomeres slightly enlarged distally, leading to slightly serrate antennae, sometimes with distal half of antenna, including eleventh antennomere, slightly widened, rarely with some antennomeres greatly enlarged; if male with greatly enlarged antennomeres, then elytra not entirely dark; female antennae filiform or moniliform, without abnormally enlarged antennomeres; middle tarsus of male rarely greatly enlarged ....................................................................................................................................... 132
132. Elytral disc with numerous erect setae ........................................................................................ 133
– Elytral disc asetose or nearly so................................................................................................... 134
133. Lateral margin of pronotum with numerous, evenly spaced setae (sometimes missing in improperly handled specimens and often hard to see at low magnification); gender female (males with bifid claws); habitus as in Fig. 89; distribution in Costa Rica and Panama ........................................ Heterochele Viswajyothi & Clark, 2021 [in part; see couplet 94]
– Pronotum with setae near anterolateral and posterolateral corners, but without numerous, evenly spaced setae along entire lateral margin; gender either male or female; males with deep, preapical notch on middle tibia; habitus as in Fig. 110; distribution from Mexico through much of South America...................................................... Trichobrotica Bechyné, 1956 [in part; see couplet 130]
134. Body broadly oval, with length less than twice width; head, thorax, abdomen, and legs entirely yellow or orange; elytra entirely black; habitus as in Fig. 115; distribution from United States through much of South America.............................................................. Trachyscelida Horn, 1893
– Body usually more elongate; color variable, but often different than described above .............. 135
135. Third antennomere twice as long as second; head and elytra entirely dark brown to black; elytra densely, rather coarsely punctate, with most punctures separated by distance subequal to diameter of puncture; body about 4 mm long; habitus as in Fig. 121; distribution in Texas ................................................................................................................ Texiluperus gen. nov.
– Not exactly fitting above description; third antennomere often less than twice as long as second; head and elytra often partially or entirely pale; elytral punctation fine to coarse; body length variable; distribution in Texas and elsewhere.............................................................................. 136
136. Abdomen of female very large, mostly not covered by elytra; eyes in dorsal view very small, separated from each other by distance more than four times width of each eye; pronotum at least as wide anteriorly as posteriorly; elytral punctation much coarser than pronotal punctation; habitus as in Fig. 49; distribution in Mexico and Guatemala (doubtfully recorded from Peru) ........................ ........................................................................................................................ Metacycla Baly, 1861
– Female abdomen covered by elytra, not abnormally enlarged; eyes usually larger; interocular distance usually less; pronotum of most (but not all) species narrower anteriorly than posteriorly; elytral punctation variable, coarse to almost absent.................................................................... 137
137. Upon close inspection, entire anterior margin of pronotum with fringe of short, closely spaced setae; male abdomen with rectangular lobe at apex .................................................................... 138
– Anterior margin of pronotum not distinctly fringed with setae, although sometimes with a few setae in lateral portion; male abdomen either with or without rectangular lobe at apex ...................... 155
138. Basal bead of pronotum complete, although fine, extending without interruption between posterolateral angles (this character obscured by extremely coarse pronotal punctation in one yellow or reddish species of Synetocephalus from California) ................................................... 139
– Basal bead of pronotum absent, or restricted to extreme lateral areas; pronotal punctation never coarse, except in metallic blue Scelidacne from Mexico ............................................................ 149
139. Rectangular lobe at apex of male abdomen at least half as long as wide, not strongly impressed towards dorsum (Fig. 198); basal antennomere subequal to maximum diameter of eye; apical spurs of tibiae large, conspicuous; elytra not metallic, varying from entirely pale to entirely dark, in many species pale with dark vittae ........................................................................................................ 140
– Rectangular lobe at apex of male abdomen either less than half as long as wide, or distinctly impressed towards dorsum; basal antennomere usually shorter than maximum diameter of eye; tibial spurs of most species relatively small, often somewhat hidden among nearby setae, sometimes entirely absent; elytral color variable, sometimes metallic ......................................................... 141
140. Aedeagus asymmetrical in dorsal view, with distal portion spatulate; each elytron pale with five long, dark stripes (one sutural, one lateral, three discal); habitus as in Fig. 136; distribution in United States and Mexico ......................................................... Triariodes Clark & Anderson, 2019
– Aedeagus symmetrical in dorsal view, at most only slightly broadened towards apex; elytral color pattern not as described above; habitus as in Fig. 124; distribution in United States and Mexico ..................................................................... Triarius Jacoby, 1887 [in part; see couplet 56]
141. Distance between antennal fossae equal to at least twice diameter of fossa; mesal frontal ridge very poorly developed, nearly continuous with antennal calli, delimited behind by shallow, sometimes indistinct impression; elytra usually pale with darker stripes or entirely pale, rarely entirely dark with faint metallic luster, never with obvious metallic luster; aedeagal orifice often with sclerotized covering; habitus as in Fig. 116; distribution in United States and Mexico .................................................................................................... Synetocephalus Fall, 1910
– Distance between antennal fossae equal to less than twice diameter of fossa; mesal frontal ridge narrower, usually separated from antennal calli by distinct sulci; supracallinal sulcus usually distinct, abruptly delimiting antennal calli behind; elytral color variable, often with distinct metallic luster; orifice of aedeagus lacking sclerotized covering .............................................................. 142
142. Elytra with conspicuous transverse impression at basal third; body, including appendages, strongly metallic; habitus as in Fig. 129; distribution in Costa Rica ............................................................... ......................................................................... Inbioluperus Clark, 1993 [in part; see couplet 177]
– Transverse impression of elytra absent or weakly developed; front tibiae or other body parts lacking metallic luster; distribution in Mexico and northward (except one pale, non-metallic species occurring from Mexico to Panama)............................................................................................. 143
143. Second abdominal ventrite of male with large, mesal appendage, which is single at base, bifurcate beyond base; dorsal surface entirely pale; habitus as in Fig. 117; distribution from Mexico to Panama ........................................................................................................ Geethaluperus gen. nov.
– If male abdominal appendages present, then not as above, either paired (separate from each other at base), or, if single, then very slender, not bifurcate; dorsal coloration variable...................... 144
144. Elytral punctation conspicuous, with punctures in most areas at least as large as ommatidium, with average distance between punctures not much greater than twice diameter of puncture; elytral surface not strongly alutaceous.................................................................................................... 145
– Punctures in most areas of elytra very fine, obsolete, or obscured by alutaceous microsculpture ............................................................................................................................. 146
145. Hind tibia of male with terminal process, nearly as long as basitarsus, located opposite terminal spur (Fig. 206); habitus as in Fig. 112; distribution in Mexico ......................................................... ........................................ Carpiradialis Niño-Maldonado & Clark, 2020 [in part; see couplet 149]
– Hind tibia lacking such process; habitus as in Fig. 119; distribution in United States and Mexico .................................................................. Mexiluperus gen. nov. [in part; see couplet 162]
146. Second abdominal ventrite of male with conspicuous appendages (Fig. 201); elytra pale, with dark vittae; head pale, similar in color to pronotum; habitus as in Fig. 122; distribution in United States (California) .................................................................................................... Cornuventer gen. nov.
– Second abdominal ventrite of male without appendages; more posterior ventrites either with or without appendages; if elytra vittate, then head dark, strongly contrasting with pale pronotum 147
147. Pronotum and elytra both black; habitus as in Fig. 123; distribution in western North America, from British Columbia to Nebraska to New Mexico to California ................................................... ............................................................................................... Pseudoluperus Beller & Hatch, 1932
– Pronotum pale; elytra variable in color, entirely dark, entirely pale, or bicolored...................... 148
148. Male elytron with distinct fovea near apicolateral angle, usually with complex modification within fovea (Fig. 232); habitus as in Fig. 128; distribution from Utah and Arizona to California and Baja California Sur ....................................... Androlyperus Crotch, 1873 [in part; see couplets 158, 161]
– Male elytra without fovea at apicolateral angle; habitus as in Fig. 118; distribution in Texas ................................................................................................................. Monoaster gen. nov.
149. Elytra noticeably costate, strongly vittate; male with large process at apex of hind tibia (Fig. 206); habitus as in Fig. 112; distribution in Mexico ................................................................................... ........................................ Carpiradialis Niño-Maldonado & Clark, 2020 [in part; see couplet 145]
– Elytra not costate or distinctly vittate (rarely, slightly darker near margins, but only indistinctly so); if male hind tibia with large apical process, then elytra entirely dark ......................................... 150
150. Pronotum and elytra densely, coarsely punctate; color almost entirely dark metallic blue; male abdomen with ventral appendages; apex of male hind tibia with large, upcurved appendage; habitus as in Fig. 135; distribution in Mexico ........................................................... Scelidacne Clark, 1998
– Pronotum and elytra not both densely, coarsely punctate; color variable, sometimes with extensive pale areas; male abdomen either with or without ventral appendages; male hind tibia without large apical appendage.......................................................................................................................... 151
151. Male front femora larger than middle or hind femora; aedeagus strongly asymmetrical in dorsal view; pronotum, of either male or female, usually with single, broad, shallowly impressed, flattened area in basal half; habitus as in Fig. 131; distribution in United States (Arizona) and nearby areas of Mexico ....................................................................................................... Lygistus Wilcox, 1965
– Male front femora not abnormally enlarged; aedeagus symmetrical in dorsal view; pronotum usually not as above, usually convex, sometimes with paired depressions................................. 152
152. All tibiae lacking terminal spurs; body of most (but not all) species longer than 5.0 mm; pronotum usually entirely pale, but, if partially dark, then male abdomen with conspicuous ventral appendages; habitus as in Fig. 127; distribution from United States to Panama ................................................... ....................................................................... Scelida Chapuis, 1875 [in part; see couplets 58, 184]
– Tibial spurs present, at least on hind legs; body of many (but not all) species shorter than 5.0 mm; pronotum variable, either pale, dark, or bicolored; male abdomen without ventral appendages...... .................................................................................................................................................... 153
153. Antennae short, reaching only slightly beyond humeri; second, third, and fourth antennomeres each about equal in length and width; habitus as in Fig. 137; distribution in United States and Mexico ............................................................................................................. Pteleon Jacoby, 1888
– Antennae longer, usually reaching to at least middle of elytra; third antennomere distinctly longer than wide...................................................................................................................................... 154
154. Orifice of aedeagus with sclerotized covering; pronotum of many (but not all) species entirely pale, contrasting with uniformly dark elytra; habitus as in Fig. 133; distribution from central to southern Mexico ............................................................. Microscelida Clark, 1998 [in part; see couplet 183]
– Aedeagal orifice without sclerotized covering; coloration not as above, either with dark or bicolored pronotum, or with partially pale elytra; habitus as in Fig. 120; distribution in southwestern United States and northwestern Mexico (including Baja California peninsula)........................................................... Amplioluperus gen. nov. [in part; see couplet 184]
155. Frons forming single, broad convexity or flattened area; frontal ridge and anterofrontal ridge not developed; antennae longer than body in male, nearly as long as body in female (Fig. 161); habitus as in Fig. 58; distribution from Guatemala to Peru ........................................... Elyces Jacoby, 1888
– Both frontal and anterofrontal ridges well developed in nearly all species; if ridges indiscernible, then antennae shorter than described above ................................................................................ 156
156. Basal bead of pronotum complete, although fine, extending without interruption between posterolateral angles .................................................................................................................... 157
– Basal bead of pronotum absent or restricted to lateral areas ....................................................... 181
157. Elytron strongly modified, with distinct lateral fovea, often with complex structure within impression; gender male.............................................................................................................. 158
– Elytron without distinct lateral fovea; gender male or female .................................................... 159
158. Lateral fovea located near mid-length of elytron (Fig. 226); abdomen without rectangular lobe at apex; habitus as in Fig. 61; distribution from United States to Panama, as well as in South America (Venezuela and Bolivia).............. Malacorhinus Jacoby, 1887 [in part; see couplets 167, 174, 180]
– Lateral fovea located near apicolateral angle of elytron (Fig. 232); abdomen with rectangular lobe at apex; habitus as in Fig. 128; distribution from Utah and Arizona to California and Baja California Sur ........................................................ Androlyperus Crotch, 1873 [in part; see couplets 148, 161]
159. Entire anterior edge of pronotum distinctly margined by fine bead ............................................ 160
– Anterior pronotal bead absent or very indistinct ......................................................................... 167
160. Apex of male abdomen clearly truncate, usually with short, rectangular, often impressed lobe; aedeagus without basal spurs (Fig. 149); distal maxillary palpomere relatively narrow, nearly parallel sided for much of length; third antennomere usually distinctly longer than second, but if nearly equal in length, then elytra entirely dark.......................................................................... 161
– Apex of male abdomen indistinctly truncate, without rectangular lobe; aedeagus with basal spurs (Fig. 148); distal maxillary palpomere usually stouter, more abruptly narrowed from base to apex; if distal maxillary palpomere narrow, then second and third antennomeres subequal in length and elytra largely pale ........................................................................................................................ 163
161. Genal distance (distance from eye margin to external edge of mouth, before base of mandible) as great as or greater than length of second antennomere; elytra entirely pale, entirely dark, or bicolored, never metallic; gender female (male elytron with distinct posterolateral fovea); habitus as in Fig. 128; distribution from Utah and Arizona to California and Baja California Sur ........................................................ Androlyperus Crotch, 1873 [in part; see couplets 148, 158]
– Genal distance less than length of second antennomere; elytral color variable, often entirely metallic; gender either male or female ........................................................................................ 162
162. Mesal frontal ridge narrow, usually forming angulate ridge; antennal calli often extending to and continuous with orbit, rarely delimited laterally by poorly defined impression; genal distance (distance from eye margin to external edge of mouth, before base of mandible) about as long as, or longer than, terminal maxillary palpomere; vertex often with alutaceous microsculpture; head and elytra dark, often metallic (Fig. 175); apex of aedeagus often truncate, emarginate, or asymmetrical, rarely symmetrical and pointed; habitus as in Fig. 130; distribution in Canada, United States, and northwestern Mexico ...................................... Scelolyperus Crotch, 1874 [in part; see couplet 170]
– If frontal ridge narrow or acutely elevated, then antennal calli delimited laterally by distinct impression; genal distance usually not more than half as great as terminal maxillary palpomere; vertex not distinctly alutaceous; head and elytra variable in color, sometimes largely pale; apical portion of aedeagus usually pointed and symmetrical, rarely strap-like and asymmetrical, never truncate or emarginate; habitus as in Fig. 119; distribution in Arizona and Mexico .................................................................. Mexiluperus gen. nov. [in part; see couplet 145]
163. Distribution in Greater Antilles (Cuba, Jamaica, Hispaniola); habitus as in Figs 47–48 .................. ................................................................................................................ Nyctiplanctus Blake, 1963
– Distribution in Lesser Antilles or in continental areas................................................................. 164
164. Third antennomere distinctly more than 1.5 times as long as second; pronotum largely or entirely pale (Fig. 189); elytral coloration variable, usually either entirely dark or bicolored (dark with transverse median band, or pale basally, dark apically); in dorsal view, aedeagus strongly asymmetrical; habitus as in Fig. 64; distribution from Mexico to South America............................ ................................................................................... Pyesia Clark, 1865 [in part; see couplet 186]
– Third antennomere not more than 1.5 times as long as second; aedeagus either symmetrical or asymmetrical................................................................................................................................ 165
165. Male antennae either longer than body, or modified (fourth through eleventh antennomeres wider than more basal antennomeres, or some antennomeres with longitudinal, asetose carina); female antennae usually nearly as long as body; aedeagus strongly asymmetrical, with orifice directed laterally; habitus as in Fig. 65; distribution from Mexico through much of South America.................................................................. Chthoneis Baly, 1864 [in part; see couplet 172]
– Antennae shorter than body, not unusually modified; aedeagal orifice directed dorsally ........... 166
166. Body 7.0–11.0 mm long; distal maxillary palpomere relatively narrow, nearly parallel sided for much of length (Fig. 156); elytra pale with darker vittae, or entirely pale; in dorsal view, aedeagus symmetrical; habitus as in Fig. 63; distribution from Mexico through much of South America, as well as in Lesser Antilles................................................................................... Pyesexora gen. nov.
– Body smaller; distal maxillary palpomere stouter, more abruptly narrowed from base to apex (Fig. 155); elytral coloration often otherwise; aedeagus either symmetrical or not; habitus as in Figs 51–55; distribution in Central and South America .................................................................... ....................................................... Zepherina Bechyné, 1958 [in part; see couplets 171, 175, 185]
167. Third antennomere much longer and broader than fourth; gender male; habitus as in Fig. 61; distribution from United States to Panama, as well as in South America (Venezuela and Bolivia) ....................................... Malacorhinus Jacoby, 1887 [in part; see couplets 158, 174, 180]
– Third antennomere equal to or shorter than fourth; gender male or female................................ 168
168. Third antennomere similar in length to second, much shorter than fourth.................................. 169
– Third antennomere much longer than second, approaching fourth in length .............................. 177
169. Terminal maxillary palpomere at least twice as long as broad, usually nearly parallel-sided in basal half (Fig. 175) .............................................................................................................................. 170
– Terminal maxillary palpomere less than twice as long as broad, rather abruptly narrowed from stout base to apex (Fig. 155)................................................................................................................. 172
170. Apex of male abdomen clearly truncate, usually with short, rectangular lobe; aedeagus without basal spurs (Fig. 149); elytra entirely dark, often metallic; habitus as in Fig. 130; distribution in Canada, United States, and northwestern Mexico ........ Scelolyperus Crotch, 1874 [in part; see couplet 162]
– Male abdomen indistinctly truncate, without rectangular lobe; aedeagus with basal spurs; elytral color variable, often not as above; distribution in Central and South America........................... 171
171. Fifth to tenth antennomeres each only about twice as long as broad, broader than basal antennomere; habitus as in Fig. 46; distribution from Panama to Brazil .......................... Hecataeus Jacoby, 1888
– Fourth to eleventh antennomeres each much more than twice as long as broad, narrower than basal antennomere; habitus as in Figs 51–55; distribution in Central and South America.......................................... Zepherina Bechyné, 1958 [in part; see couplets 166, 175, 185]
172. Male antennae either longer than body or modified (fourth through eleventh antennomeres wider than more basal antennomeres, or some antennomeres with longitudinal, asetose carina); female antennae usually nearly as long as body; aedeagus strongly asymmetrical, with orifice directed laterally; habitus as in Fig. 65; distribution from Mexico through much of South America.................................................................. Chthoneis Baly, 1864 [in part; see couplet 165]
– Antennae usually shorter than body, not unusually modified; aedeagus symmetrical or less strongly asymmetrical, with orifice directed dorsally................................................................................ 173
173. Pronotum wider in anterior half than in posterior half, with lateral margins sinuate.................. 174
– Pronotum not wider anteriorly; lateral margins of pronotum rounded (Fig. 185)....................... 176
174. Pronotum nearly as long as wide (Fig. 187); habitus as in Fig. 61; distribution from United States to Panama, as well as in South America (Venezuela and Bolivia) .................................................... .................................................... Malacorhinus Jacoby, 1887 [in part; see couplets 158, 167, 180]
– Pronotum much shorter than wide; distribution in Central and South America.......................... 175
175. Vertex black; elytra testaceous with black markings forming broad, transverse band at base and another black band beyond middle; sutural and apical margins of elytra also black; body 5.0– 6.4 mm long; body shape as in Fig. 57; distribution in Panama ........................................................ ................................................................... Masurius Jacoby, 1888 [in part; see couplets 179, 186]
– Color or size not as above; habitus as in Figs 51–55; distribution in Central and South America.......................................... Zepherina Bechyné, 1958 [in part; see couplets 166, 171, 185]
176. Pronotum twice as wide as long; antennae not attaining elytral apex; female abdomen incised at apex; habitus as in Fig. 69; distribution in South America........................ Uaupesia Bechyné, 1957
– Pronotum often distinctly less than twice as wide as long; male antennae of some (but not all) species extending beyond elytral apex; female abdomen not incised at apex; habitus as in Fig. 60; distribution in Central and South America .............................................. Sonyadora Bechyné, 1958
177. Male abdomen with short, rectangular lobe at apex; aedeagus without basal spurs; entire body, including appendages, strongly metallic; habitus as in Fig. 129; distribution in Costa Rica .................................................................. Inbioluperus Clark, 1993 [in part; see couplet 142]
– Male abdomen slightly truncate, but without rectangular lobe; aedeagus with basal spurs; body of most species not entirely metallic................................................................................................ 178
178. Body 6.5–13.0 mm long; habitus as in Fig. 56; distribution from Mexico through much of South America and in Lesser Antilles..................................................................... Exora Chevrolat, 1836
– Body smaller................................................................................................................................ 179
179. Terminal maxillary palpomere shorter than penultimate palpomere; elytra variable in color, but often entirely dark; habitus as in Fig. 57; distribution in Central and South America...................................................... Masurius Jacoby, 1888 [in part; see couplets 175, 186]
– Terminal maxillary palpomere longer than penultimate palpomere; elytra usually bicolored.... 180
180. Pronotum widest slightly anterior to mid-length; lateral pronotal margins rounded; male fourth abdominal ventrite of some (but not all) species with posteromesal irregularity, tooth, or long spine (Fig. 200); habitus as in Fig. 62; distribution in South America.............................................................................. Trigonexora Bechyné & Bechyné, 1969
– Pronotum widest slightly behind anterior margin; lateral margins of pronotum sinuate (Fig. 187); habitus as in Fig. 61; distribution from United States to Panama, as well as in South America (Venezuela and Bolivia).............. Malacorhinus Jacoby, 1887 [in part; see couplets 158, 167, 174]
181. Apex of male abdomen with short, rectangular, often impressed lobe; aedeagus lacking basal spurs; terminal maxillary palpomere distinctly longer than broad, nearly parallel-sided for much of length, usually comparatively narrow...................................................................................................... 182
– Apex of male abdomen slightly truncate, but without rectangular lobe; aedeagus with basal spurs; terminal maxillary palpomere only about as long as broad, rather abruptly narrowed from stout base to apex.................................................................................................................................. 185
182. Basitarsus of male hind leg enlarged, much different in form from basitarsi of front and middle legs (Fig. 203); elytra conspicuously vittate; habitus as in Fig. 125; distribution in Texas and northern Mexico ....................................................................................................... Keitheatus Wilcox, 1965
– Basitarsus of male hind leg not conspicuously enlarged; elytra usually unicolorous, sometimes pale with vaguely darker margins ....................................................................................................... 183
183. Aedeagus orifice with sclerotized covering; at least hind tibiae with terminal spurs; abdomen lacking ventral appendages; pronotum of many (but not all) species entirely pale; elytra largely or entirely dark, usually metallic; body 3.1–4.9 mm long; habitus as in Fig. 133; distribution from central to southern Mexico .............................. Microscelida Clark, 1998 [in part; see couplet 154]
– Aedeagal orifice usually without sclerotized covering; if sclerotized covering present, then terminal spurs absent from all tibiae and abdomen with ventral appendages; coloration variable, either as above or not ................................................................................................................................. 184
184. Pronotum usually entirely pale; if pronotum partially black, then male abdomen with ventral appendages; tibiae without terminal spurs; elytra usually entirely dark; if elytra partially pale, then body longer than 5.0 mm; habitus as in Fig. 127; distribution from United States to Panama ........................................................... Scelida Chapuis, 1875 [in part; see couplets 58, 152]
– Pronotum often partially or entirely dark; if pronotum entirely pale, then elytra largely or entirely pale also, tibiae with terminal spurs, and body length less than 5.0 mm; habitus as in Fig. 120; distribution in southwestern United States and northwestern Mexico (including Baja California peninsula)........................................................... Amplioluperus gen. nov. [in part; see couplet 154]
185. Third antennomere short, less than 1.5 times as long as second; habitus as in Figs 51–55; distribution in Central and South America ........ Zepherina Bechyné, 1958 [in part; see couplets 166, 171, 175]
– Third antennomere at least 1.5 times as long as second .............................................................. 186
186. Upon close inspection, anterior edge of pronotum margined by fine bead; habitus as in Fig. 64; distribution from Mexico to South America............... Pyesia Clark, 1865 [in part; see couplet 164]
– Anterior margin of pronotum without bead; habitus as in Fig. 57; distribution in Panama ....................................................... Masurius Jacoby, 1888 [in part; see couplets 175, 179]
description: Published as part of Viswajyothi, Keezhpattillam & Clark, Shawn M., 2022, New World genera of Galerucinae Latreille, 1802 (tribes Galerucini Latreille, 1802, Metacyclini Chapuis, 1875, and Luperini Gistel, 1848): an annotated list and identification key (Coleoptera: Chrysomelidae), pp. 1-102 in European Journal of Taxonomy 842 on pages 37-60, DOI: 10.5852/ejt.2022.842.1945, http://zenodo.org/record/7222499