Phytobia
Creators: name: Carvalho-Filho, Fernando S.
name: Cabá, Emiliano N.
name: Monteiro, Nilton J. S.
name: De-Souza, Caroline C.
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Agromyzidae
Phytobia

description: Key to the males of Neotropical species of Phytobia (adapted from Sousa & Couri (2017))
This key is based only on males, since females of most species remain unknown.
1. Presutural dorsocentral seta absent....................................................................... 2
– Presutural dorsocentral seta present...................................................................... 7
2. Two postsutural dorsocentral setae....................................................................... 3
– Three postsutural dorsocentral setae...................................................................... 4
3. Mid tibia with one posterodorsal seta on middle third; hypandrium unusually elongate, constricted towards apex (Fig. 93 in Sousa & Couri (2017)); distiphallus composed of two separated tubules in ventral view (Figs. 94 and 95 in Sousa & Couri (2017); base of ejaculatory apodeme bowl-shaped [Costa Rica, Jamaica]............................ P. unica Spencer
– Mid tibia with two posterodorsal setae on middle third; hypandrium U-shaped; distiphallus bifid with very spiny surrounding membrane (Figs. 90 and 91 in Sousa & Couri (2017)); ejaculatory apodeme sickle-shaped, with its broader part about 2.5 times wider than constricted area at base (Fig. 92 in Sousa & Couri (2017)) [Brazil]............... P. spinosula Sousa & Couri
4. Mid tibia with one posterodorsal seta on middle third........................................................ 5
– Mid tibia with two posterodorsal setae on middle third....................................................... 6
5. Frons black; epandrium densely setulose; hypandrium about 4/5 length of phallapodeme (Fig. 96 in Sousa & Couri (2017)); phallus about 1.2 times as along as phallapodeme, basiphallus short but rather well-developed, distiphallus as two long tubules (Fig. 97 in Sousa & Couri (2017)) [Peru]................................................. P. mentula Sasakawa
– Frons brownish-black on upper half, orange-brown on lower half; hypandrium ¾ length of phallapodeme (Fig. 99 in Sousa & Couri (2017)); phallus very long, only a little shorter than phallapodeme, basiphallus narrow, distiphallus membranous distally, with distinct basal tube and pair of spinose, narrow sclerites on lateral side before end (Fig. 100 in Sousa & Couri (2017)) [Guatemala]................................................................... P. guatemalensis Sasakawa
6. Scape and pedicel yellow; frons with lower half testaceous and upper half brownish-black; mid and hind tibiae entirely light brown; surstylus with 23 to 26 spines; phallus elongated and tubular (Fig. 103 in Sousa & Couri (2017)) [Peru]............................................................................................. P. pipinna Sasakawa
– Scape and pedicel dark brown; frons yellow on lower half with yellow microtomentum on upper half; all legs dark brown, apex of fore femur yellow; surstylus without spines; phallus composed of large shapeless membranous areas (Figs. 50 and 51 in Sousa & Couri (2017)) [Brazil]................................................. P. flavifrontalis Sousa & Couri
7. Abdomen entirely black............................................................................... 8
– Abdomen mostly yellow.............................................................................. 13
8. Wing spotted; distiphallus short (as long as cercus), bifid distal portion in lateral view (Fig. 55 in Sousa & Couri (2017)) [Brazil, Panama].............................................................................. P. kallima (Frost)
– Wing entirely clear; distiphallus short or elongate (longer than cercus), but never with bifid distal portion............... 9
9. Mid tibia with three posterodorsal setae on middle third; distiphallus almost rectangular in lateral view (Fig. 76 in Sousa & Couri (2017)) [Brazil]......................................................... P. planipalpis Sousa & Couri
– Mid tibia with one or two posterodorsal setae on middle third; distiphallus not rectangular in lateral view.............. 10
10. Medium sized species, wing length 3.4 mm; scutum deep black, moderately shining; phallus asymmetrical (Fig. 104 in Sousa & Couri (2017)) [Chile, Peru].......................................................... P. peruensis Spencer
– Smaller species, wing length 2.1–2.3 mm; scutum brown, with grey microtomentum; phallus asymmetrical or symmetrical.. .................................................................................................. 11
11. Frons entirely matte black with grey microtomentum; surstylus triangular with about 45 setae (Fig. 66 in Sousa & Couri (2017)); distiphallus elongate (Fig. 67 in Sousa & Couri (2017)) [Brazil]................. P. multisetosa Sousa & Couri
– Frons matte black with lower half reddish-brown or with reddish-brown close to lunule; surstylus rounded with at most 20 setae; distiphallus sclerotized with two medium arms (Figs. 84 and 85 in Sousa & Couri (2017)) [Brazil].............. 12
12. Pleuron and abdominal tergites dark brown with light yellow markings (Fig. 5A); surstylus with a row of stout spines (Fig. 6E).................................................................................... P. pium sp. nov.
– Pleuron and abdominal tergites entirely dark brown; surstylus without stout spines............. P. simpla Sousa & Couri
13. Legs entirely brown or black........................................................................... 14
– Legs with at least the apex of fore femur yellow........................................................... 19
14. First flagellomere testaceous-orange; distal portion of distiphallus bearing many tiny cuticular membranous spines (Fig. 107 in Sousa & Couri (2017)) [Ecuador]...................................................... P. spinulosa Sasakawa
– First flagellomere black; distal portion of distiphallus without tiny cuticular membranous spines..................... 15
15. Posterior margin of black marking on scutum, between the intra-alar stripes, arched (Fig. 108 in Sousa & Couri (2017)); dorsocentrals 4+1; surstylus with a papilla dorsally (Fig. 109 in Sousa & Couri (2017)) [Colombia].. P. setitibialis Sasakawa
– Posterior margin of black marking on scutum, between the intra-alar stripes, angled (Figs. 114 and 112 in Sousa & Couri (2017) and Fig. 61 in Frick (1959)); dorsocentrals 3+1; surstylus without a papilla dorsally............................... 16
16. Scutum with dark area conspicuously matte grey, dark area not divided into separate bands laterally (Fig. 112 in Sousa & Couri (2017)); abdomen with brownish-yellow ground colour, all tergites except first shining black centrally and broadly black at sides [Dominica]...................................................................... P. matura Spencer
– Scutum with dark area shining black, sometimes divided into separate bands laterally; abdomen predominantly yellow with black spots only posterior to tergite 4.................................................................... 17
17. Abdomen yellow, with tergites 5 and 6 black; phallus with distinctly elongate distal tubules (Fig. 113 in Sousa & Couri (2017)) ......................................................................... P. xanthophora (Schiner)
– Abdomen yellow, with tergites 5 and 6 with lateral and central spots. Phallus not composed of elongate tubules distally... 18
18. Black marking between the intra-alar stripes with a median cleft in the posterior margin (Fig. 114 in Sousa & Couri (2017)); phallus, in ventral view, clubbed (Fig. 117 in Sousa & Couri (2017)) [Ecuador]................ P. ecuadorensis Spencer
– Black marking between the intra-alar stripes continuous, without a median cleft (Fig. 61 in Frick (1959)); phallus almost quadrate in ventral view (Fig. 119 in Sousa & Couri (2017)) [Costa Rica, Cuba, Mexico, Panama, Puerto Rico].............................................................................................. P. picta (Coquillett)
19. Wing distinctly brown along anterior margin.............................................................. 20
– Wing not brown along anterior margin................................................................... 25
20. Wing length greater than 5 mm; first flagellomere orange; scutellum yellow, with sub-basal lateral dark brown spot; phallus as in Figs. 121 and 122 in Sousa & Couri (2017) [Brazil].......................................... P. lanei Spencer
– Wing length at most 4.0 mm; first flagellomere brown or black; scutellum entirely yellow or yellow with sub-basal lateral dark brown spot......................................................................................... 21
21. 4 postsutural dorsocentrals............................................................................ 22
– 3 postsutural dorsocentrals............................................................................ 23
22. Wing membrane around veins r-m and bm-cu not infuscate (Fig. 2E); distiphallus medially divided in ventral view (Fig. 3E) [Brazil]........................................................................... P. munduruku sp. nov.
– Wing membrane infuscate along veins r-m and bm-cu (Fig. 123 in Sousa & Couri (2017)); distiphallus not divided in ventral view (Fig. 125 in Sousa & Couri (2017)) [Brazil, Costa Rica (doubtful record), Ecuador]............. P. rabelloi Spencer
23. Lunule yellow; mid tibia with one posterodorsal seta on middle third; distiphallus bifid distally (Figs. 127 and 128 in Sousa & Couri (2017)) [Peru]............................................................. P. monsonensis Sasakawa
– Lunule silvery; mid tibia with two posterodorsal setae on middle third; distiphallus not bifid........................ 24
24. Tergites 5 and 6 mostly yellow with brown spots (Fig. 1C); epandrium and surstylus with spines (Fig. 3A, B) [Brazil]......................................................................................... P. espositae sp. nov.
– Tergites 5 and 6 entirely black; epandrium and surstylus without spines (Fig. 82 in Sousa & Couri (2017)) [Brazil]........................................................................................... P. pyri Sousa & Couri
25. 2 presutural dorsocentrals; distiphallus composed of two lobes tapering distally (Figs. 129 and 130 in Sousa & Couri (2017)) [Costa Rica, Panama].............................................................. P. dorsocentralis (Frost)
– 1 presutural dorsocentral; distiphallus otherwise shaped..................................................... 26
26. Frons with lower half brown or reddish-brown, or only reddish-brown above lunule............................... 27
– Frons entirely matte black............................................................................. 29
27. Wing length greater than 3.5 mm; posterior margin of black marking on scutum with two pairs of narrow stripes projected toward scutellum (Fig. 131 in Sousa & Couri (2017)); anterior margin of scutellum with a black rectangular marking (Fig. 131 in Sousa & Couri (2017)) [Brazil]...................................................... P. kuhlmanni Spencer
– Wing length 2.25–2.3 mm; posterior margin of black marking on scutum with one pair of wide stripes projected toward scutellum or without stripes (Figs. 28 and 31 in Sousa & Couri (2017)); anterior margin of scutellum without a black rectangular marking (Figs. 28 and 31 in Sousa & Couri (2017)) ......................................................... 28
28. Scape and pedicel almost entirely orange-brown; first flagellomere orange-brown; scutum colour pattern: grey pollinose presuturally and shinning black postsuturally; posterior margin of black marking on scutum with black intra-alar stripe reaching posterior margin of scutum; distiphallus sclerotized with two arms (Figs 42 and 43 in Sousa & Couri (2017)) [Brazil].................................................................................. P. communis Sousa & Couri
– Scape and pedicel brown; first flagellomere brown, light brown apically; scutum colour pattern: presuturally and postsuturally shining black; posterior margin of black marking on scutum with black intra-alar stripe not reaching posterior margin of scutum; distiphallus very complex, as in Figs 61 and 62 in Sousa & Couri (2017) [Brazil]... P. megapodema Sousa & Couri
29. Wing slightly infuscate, with brown area above Sc and in cell cup [Brazil]............... P. cacaulandia Sousa & Couri
– Wing hyaline....................................................................................... 30
30. Scutellum yellow, with sub-basal lateral dark brown spot (Fig. 7B; Fig. 33 in Sousa & Couri (2017)); mid tibia with one posterodorsal median seta............................................................................. 31
– Scutellum entirely yellow; mid tibia with two or three posterodorsal median setae................................. 32
31. Posterior margin of black marking on scutum indentated between the intra-alar stripes (Fig. 33 in Sousa & Couri (2017)); distiphallus elongate and boot-shaped laterally, composed of two small tubules distally (Fig. 71 in Sousa & Couri (2017)) [Brazil].......................................................................... P. niheii Sousa & Couri
– Posterior margin of black marking on scutum not indentated, almost straight, between the intra-alar stripes; distiphallus composed of many tangled membranous tubules (Figs. 8A–B) [Brazil]....................... P. pluviasilvae Boucher
32. Wing length equal to or greater than 2.8 mm; lunule testaceous, densely microtomentose; anepisternum largely black, with small, semicircular yellow spot along hind margin (Fig. 136 in Sousa & Couri (2017)); distiphallus composed of two clubbed tubules entirely fused with each other (Figs 140 and 141 in Sousa & Couri (2017)) [Peru]........... P. resupitata Zlobin
– Wing length 1.7 to 2.2 mm; lunule silvery; anepisternum with yellow upper portion and dark brown lower portion; distiphallus not composed of two clubbed tubules entirely fused with each other............................................ 33
33. Posterior margin of black marking on scutum not projected toward scutellum on the intra-alar area (Fig. 31 in Sousa & Couri (2017)); distiphallus almost circular in lateral view (Fig. 58 in Sousa & Couri (2017)) [Brazil].... P. lamasi Sousa & Couri
– Posterior margin of black marking on scutum projected as a glossiform stripe toward scutellum on the intra-alar area (Figs. 26, 29 and 35 in Sousa & Couri (2017)); distiphallus not circular in lateral view...................................... 34
34. Posterior margin of black marking on scutum with two pairs of glossiform stripes on the intra-alar and supra-alar areas (Figs. 26, 29 and 35 in Sousa & Couri (2017)); posterior margin of surstylus with or without spines (Figs. 37, 46 and 48 in Sousa & Couri (2017)) ....................................................................................... 35
– Posterior margin of black marking on scutum with one pair of glossiform stripes on the intra-alar area (Fig. 4B); posterior margin of surstylus with spines (Fig. 6B) [Brazil]........................................... P. piscivora sp. nov.
35. Mid tibia with three posterodorsal median setae; posterior margin of epandrium with two spines along ventral margin (Fig. 37 in Sousa & Couri (2017)) [Brazil]................................................. P. amazonica Sousa & Couri
– Mid tibia with two posterodorsal median setae; posterior margin of epandrium without spines along ventral margin...... 36
36. Surstylus clubbed in ventral view, with two spines (Fig. 46 in Sousa & Couri (2017)); distiphallus membranous, sclerotized centrally, without spines (Figs 45 and 46 in Sousa & Couri (2017)) [Brazil].................. P. delicata Sousa & Couri
– Surstylus rounded in ventral view, without spines (Fig. 88 in Sousa & Couri (2017)); distiphallus entirely sclerotized and bulbshaped with two spines distally (Figs 87 and 88 in Sousa & Couri (2017)) [Brazil]........... P. spinifera Sousa & Couri
description: Published as part of Carvalho-Filho, Fernando S., Cabá, Emiliano N., Monteiro, Nilton J. S. & De-Souza, Caroline C., 2025, Four new species of Phytobia Lioy (Diptera: Agromyzidae) from the Brazilian Amazon, with an updated key to the Neotropical species, pp. 448-464 in Zootaxa 5604 (4) on pages 461-463, DOI: 10.11646/zootaxa.5604.4.2, http://zenodo.org/record/15213994