Zyras STEPHENS 1833
Creators: name: Assing, Volker
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Staphylinidae
Zyras

description: 3.2 Key to the species of the subgenus Zyras of the Oriental Region (sensu SCHÜLKE & SMETANA 2015), exclusive of India, Sri Lanka, and Myanmar
In all, 45 species are currently known from the southeastern Oriental regions (comprising Thailand, Laos, Vietnam, Peninsular Malaysia, and the Sunda Islands).
A positive identification of females without reference material may not always be possible. The same applies to aberrant (e.g., regarding coloration) or nanistic specimens. Two variable species, Z. gratellus and Z. punctipennis, key out in more than one couplet.
1. Punctation of pronotum and elytra conspicuously coarse and dense (e.g., Fig. 30). ................................................. 2
– Punctation of pronotum and elytra not conspicuously coarse and dense (though sometimes very fine and dense, or only the elytra with coarse and dense punctation). ................................................................................................... 3
2. Punctation of pronotum and elytra strongly and conspicuously coarsely granulose (Fig. 30). Body smaller and more slender, of predominantly brown coloration. Antennae reddish (Fig. 7). Pronotum nearly as long as broad, strongly convex in cross-section, and with sinuate lateral margins in dorsal view (Fig. 30). Median lobe of aedeagus as in Figs 66–67. Borneo. ....................................................................................................................................... granulipennis
– Punctation of pronotum and elytra not distinctly granulose. Body larger and more robust, of predominantly black coloration. Antennae bicoloured, dark-brown to blackish-brown with the apical 1–2 antennomeres yellow. Pronotum distinctly transverse, moderately convex in cross-section; lateral margins not sinuate in dorsal view. Median lobe of aedeagus as in ASSING (2017: figures 266–267, 271–272). Borneo, Peninsular Malaysia. ............ montanus
3. Forebody with conspicuously dense and fine punctation. Small species; length of forebody 1.7–2.1 mm. Antennae slender, preapical antennomeres not transverse. ............................................................................................................ 4
– Punctation of forebody not conspicuously dense and fine. Mostly larger species. Preapical antennomeres mostly transverse. ............................................................................................................................................................................. 5
4. Punctation of forebody finer and denser (ASSING 2017: figure 75). Pronotum dark-brown, of similar coloration as head (ASSING 2017: figure 75). Median lobe of aedeagus as in ASSING (2017: figures 239–241). Sulawesi. ............. ............................................................................................................................................................................. densissimus
– Punctation of forebody less fine and less dense (Fig. 23). Pronotum pale-reddish, distinctly contrasting with the dark-brown to blackish head. Median lobe of aedeagus as in Figs 59–60. Widespread in the Oriental region. ....... ...................................................................................................................................................................................... bryanti
5. Antennae short (<1.5 mm long) and clavate; antennomeres IV–X transverse, X at least approximately twice as broad as long. Body rather small (length of forebody 2.4–2.5 mm) and of predominantly reddish coloration, with the head reddish to reddish-brown and the pronotum pale reddish. Forebody moderately sparsely or very sparsely punctate. ............................................................................................................................................................................... 6
– Character combination different. Antennae usually longer and more slender, with antennomere IV weakly transverse at most. Species of similarly small size have at least the head darker. ................................................................ 7
6. Antennomere IV disc-shaped, approximately twice as broad as long (Fig. 17). Elytra with very sparse punctation; interstices on average more than twice as broad as diameter of punctures (Fig. 22). Pronotum small in relation to head, approximately 1.2 times as broad as head (Fig. 22). Male sexual characters unknown. Borneo. ...... pallipyga
– Antennomere IV noticeably transverse, but not disc-shaped (Fig. 16). Elytra with moderately dense punctation; interstices on average twice as broad as diameter of punctures at most (Fig. 20). Pronotum large in relation to head,> 1.35 times as broad as head (Fig. 20). Median lobe of aedeagus as in Figs 53–54. Java. ...................... elegantulus
7. Pronotum reddish or pale-reddish, strongly constrasting with the blackish head and elytra. Abdomen distinctly bicoloured, with segments III–V or III–VI reddish and the posterior segments at least partly blackish. .............. 8
– Coloration of forebody different. .................................................................................................................................... 10
8. Antennomere XI dark-brown to black (ASSING 2017: figure 20). Legs of uniformly yellowish coloration. Pronotum strongly transverse, 1.15–1.18 times as broad as long. Elytra with coarser and sparser punctation (ASSING 2017: figure 58). Median lobe of aedeagus as in ASSING (2017: 166–167). Widespread (ASSING 2017: map 8). .............. ............................................................................................................................................................................. alternans
– Apical 1–3 antennomeres yellow, much paler than antennomeres IV–VII. Legs with at least the apices of the mesoand metafemora slightly to distinctly infuscate. Elytra with denser and finer punctation. Median lobe of aedeagus of different shape. ................................................................................................................................................................ 9
9. Profemora and the apical halves of the meso- and metafemora blackish. Antennomere X blackish. Pronotum dark-reddish. Elytra with distinct punctation. Median lobe of aedeagus as in PACE (1986a: figures 120–121). Thailand. ................................................................................................................................................................ thaiorum
– Apices of femora only slightly and narrowly infuscate; profemora often uniformly yellowish. Antennomere X and often also antennomere IX yellowish. Pronotum pale-reddish. Elytra with very fine punctation. Median lobe of aedeagus as in ASSING (2016a: figures 274–281). Widespread (ASSING 2017: map 8). ................................. geminus
10. Antennomere XI pale-yellow to dark-yellow. ................................................................................................................ 11
– Antennomere XI reddish to black. (In cases of doubt regarding this character follow both alternatives.). ......... 26
11. Small (length of forebody approximately 2.4 mm) and micropterous species with short elytra and reduced hind wings; elytra 0.65–0.75 times as long as pronotum. ..................................................................................................... 12
– Macropterous species with longer elytra and long hind wings. Body usually larger. .............................................. 13
12. Antennae uniformly dark-yellowish (Fig. 4). Pronotum and elytra with coarse and dense punctation (Fig. 21). Antennomere XI shorter than the combined length of antennomeres IX and X; antennomere X weakly transverse (Fig. 4). Anterior abdominal tergites dark-brown (Fig. 44). Mesofemora uniformly yellowish. Median lobe of aedeagus as in PACE (2008: figures 98–99). Borneo. ................................................................................ kinabaluensis
– Antennomeres IV–X dark-brown (ASSING 2017: figure 34). Pronotum and elytra with sparser and finer punctation (ASSING 2017: figure 70). Antennomere XI approximately as long as the combined length of antennomeres IX and X; antennomere X distinctly transverse (ASSING 2017: figure 34). Meso- and metafemora apically infuscate. Median lobe of aedeagus as in ASSING (2017: figures 212–213). Thailand. ............................................................... ambulans
13. Legs bicoloured, yellowish with at least the metafemora distinctly infuscate apically. Pronotum brown to black. .............................................................................................................................................................................................. 14
– Legs uniformly yellowish, apices of meso- and metafemora in one variable large species with reddish pronotum sometimes indistinctly darker. ........................................................................................................................................ 19
14. Meso- and metafemora apically narrowly infuscate. Elytra with very dense punctation. Antennae not particularly long and slender; antennomere IV indistinctly oblong at most. ................................................................................ 15
– Meso- and metafemora apically extensively infuscate. Elytra with moderately dense punctation. Antennae long and slender; antennomere IV at least approximately twice as long as broad (species of the Z. nitens group). .............. 16
15. Body black. Antennomeres IX–XI pale-yellow. Elytra with distinctly finer punctation (ASSING 2017: figure 77). Anterior impressions of tergites III and IV with very fine and scattered non-setiferous punctation (ASSING 2017: figure 115). Median lobe of aedeagus as in ASSING (2017: figures 250–251). Sulawesi. .......................... densihirtus
– Head and pronotum brown (Fig. 19); elytra bicoloured, reddish with the postero-lateral portions infuscate Fig. 19); abdomen partly reddish to reddish-brown (Fig. 34). Elytra with coarse punctation (Fig. 19). Anterior impressions of tergites III and IV with coarse and dense non-setiferous punctation (Fig. 34). Male sexual characters unknown. Java. .................................................................................................................................................................. punctipennis
16. Pronotum more strongly transverse, approximately 1.2 times as broad as long (Fig. 31). Pronotum and elytra with sparser and finer punctation (Fig. 31). Median lobe of aedeagus as in Figs 81–82. Laos. ..................... rutrilobatus
– Pronotum more slender, approximately 1.1 times as long. Pronotum and elytra with denser and coarser punctation. .............................................................................................................................................................................................. 17
17. Species of slightly smaller body size and with weakly infuscate apical halves of the meso- and metafemora. Male sternite VIII apically acute and somewhat bifid (ASSING 2017: figure 221). Median lobe of aedeagus as in ASSING (2017: figures 216–217). Peninsular Malaysia. ........................................................................................................ nitens
– Slightly larger species with the apical halves of the meso- and metafemora blackish. Male sternite VIII and median lobe of aedeagus of different shapes. (Male sexual characters of Z. brignolii are unknown.). ................................ 18
18. Antennae more slender; antennomeres IX–X distinctly oblong. Antennomere XI pale-yellowish. Male sternite VIII obtusely pointed posteriorly. Ventral process of aedeagus (PACE 2003: figures 87–88) conspicuously broad in ventral view. Peninsular Malaysia; Borneo. .................................................................................................... nigerrimus
– Antennae less slender; antennomeres IX–X weakly transverse (ASSING 2017: figure 15). Antennomere XI darkyellowish. Male sexual characters unknown. Thailand; China: Yunnan. ....................................................... brignolii
19. Pronotum reddish. Large to very large species (species of the Z. hirtus group). ...................................................... 20
– Pronotum dark-brown to blackish. Species of relatively small to large size. ............................................................. 22
20. Head pale-reddish, of similar coloration as pronotum; elytra dark-brown to blackish with the anterior margin reddish (ASSING 2017: figure 61); abdomen distinctly bicoloured, with tergites III–V reddish and VI–VIII extensively blackish (ASSING 2017: figure 114). Median lobe of aedeagus as in ASSING (2017: figures 187–188). Thailand; Peninsular Malaysia. .............................................................................................................................................. russiceps
– Head reddish-brown to black, darker than the pronotum; elytra uniformly reddish, or reddish with the posterolateral portions more or less distinctly infuscate; abdomen not distinctly bicoloured. Larger species. ................ 21
21. Largest species of the subgenus in the Oriental region; length of forebody 4.0– 4.3 mm. Pronotum slender, less than 1.1 times as broad as long (ASSING 2017: figure 76). Elytra with coarse punctation (ASSING 2017: figure 76). Anterior impressions of tergites III–V with coarse and dense non-setiferous punctation (ASSING 2017: figure 113). Median lobe of aedeagus as in ASSING (2017: figures 245–246). Sulawesi. ........................................................... titan
– Large species, but less so than Z. titan; length of forebody less than 4.0 mm. Pronotum more transverse, approximately 1.15 times as broad as long. Elytra with fine and dense punctation. Anterior impressions of tergites III–V with fine and sparse non-setiferous punctation. Median lobe of aedeagus as in ASSING (2017: 276–277). Widespread (ASSING 2017: map 10). ................................................................................................................................ preangeranus
22. Elytra with conspicuously coarse and dense punctation (Fig. 19). Pronotum strongly convex in cross-section and weakly transverse, approximately 1.1 times as broad as long (Fig. 19). Head and pronotum dark-brown to blackishbrown; elytra dark-reddish with infuscate postero-lateral portions (Fig. 19). Large species; body length 6.5–8.0 mm; length of forebody 3.0– 3.5 mm. Male sexual characters unknown. Java, Borneo. ................................ punctipennis
– Elytral punctation less coarse and less dense. Character combination different. ..................................................... 23
23. Abdomen distinctly bicoloured; tergites III–V reddish and tergites VI–VII extensively black (ASSING 2016a: figure 112). Elytra distinctly bicoloured with the anterior portion reddish and the posterior portion sharply black (ASSING 2016a: figure 56). Punctation of elytra coarse (ASSING 2016a: figure 56). Antennomeres IX–X or VIII–X pale-yellowish, sharply contrasting with the black antennomeres IV–VII (Assing 2016a: figure 1). Median lobe of aedeagus as in ASSING (2016a: figures 176–177). Myanmar; Vietnam. .......................................................... malaisei
– Abdomen not distinctly bicoloured. ............................................................................................................................... 24
24. Small species; length of forebody 2.1–2.4 mm. Antennomere XI elongate, approximately as long as the combined length of VIII–X (ASSING 2017: figures 26, 39). Pubescence inconspicuous, moderately long, suberect, and moderately dense. Median lobe of aedeagus as in ASSING (2017: figures 223–224, 234–235). Widespread. ................... gratellus
– Larger species; length of forebody> 2.7 mm. Antennomere XI short and of conical shape, approximately as long as the combined length of IX and X at most. (ASSING 2016b: figure185). Pubescence longer, denser, and sub-erect to erect. Species of the Z. hirtus group. .......................................................................................................................... 25
25. Pronotum with coarse and rather dense punctation (ASSING 2017: figure 78). Antennae shorter and with more transverse antennomeres IV–X; antennomeres IV weakly transverse and X more than twice as broad as long (ASSING 2017: figure 38). Abdominal tergites VI and VII with very dense and rather fine non-setiferous punctation anteriorly (ASSING 2017: figure 16). Median lobe of aedeagus as in ASSING (2017: figures 255–256). Sulawesi. ........................................................................................................................................................................ nigrihirtus
– Pronotum with less distinct and less coarse punctation (ASSING 2016b: figure 184). Antennae longer and with less transverse antennomeres IV–X; antennomeres IV approximately as long as broad and X less than twice as broad as long (ASSING 2016b: figure185). Abdominal tergites VI and VII with distinctly less fine and less dense punctation (ASSING 2016b: figure 186). Pubescence of dorsal surface long, dense, and sub-erect to erect; all sternites with long, dense, and erect pubescence. Median lobe of aedeagus as in ASSING (2016b: figures 461–462). Bali. ................................................................................................................................................................ wunderlei
26. Legs bicoloured; femora brown to black with the bases of the meso- and metafemora yellow. Forebody of uniformly dark-brown to black coloration. Species of the Z. hirtus group. ................................................................................. 27
– Legs of uniformly yellowish coloration. ......................................................................................................................... 28
27. Smaller species; length of forebody 2.8 mm. Antennae shorter, 1.7 mm long; antennomere IV weakly transverse; antennomeres IX–X more than twice as broad as long (ASSING 2015: figure 57). Abdomen partly brownish. Male sexual characters unknown. Vietnam. ................................................................................................................. funestus
– Larger species; length of forebody 3.6–3.7 mm. Antennae 2.4–2.5 mm long; antennomere IV noticeably oblong; antennomeres IX–X less than twice as broad as long (Figs 11–12). Abdomen black, except for the brown posterior margins of tergites VII and VIII (Fig. 49). Median lobe of the aedeagus as in Figs 96–97. Vietnam, Laos. .............. .............................................................................................................................................................................. hirtiventris
28. Pronotum and elytra with very sparse and fine punctation; interstices on elytra on average more than twice as broad as diameter of punctures (Fig. 24). Median lobe of aedeagus as in Figs 56–57. Java. ....................... facundus
– Pronotum and elytra with much denser and usually also coarser punctation. ......................................................... 29
29. Abdomen bicoloured with segments III–V or III–VI reddish and VI–VIII or VII–VIII extensively infuscate. For Z. quasar from Vietam with a posteriorly somewhat infuscate tergite V (ASSING 2016b: figure 180) follow this alternative. .......................................................................................................................................................................... 30
– Abdomen of uniformly reddish or blackish coloration, or reddish with tergite VI (and sometimes also the anterior portion of tergite VII weakly) infuscate. ........................................................................................................................ 34
30. Pronotum with fine and sparse punctation; dorsal surface smooth, not impressed, except for the usual posteromedian impression. ........................................................................................................................................................... 31
– Pronotum with coarse and rather dense, or coarse and very irregularly distributed punctation; in the latter case pronotum with uneven surface (punctation situated in more or less pronounced impressions). ......................... 32
31. Antennomere XI strongly elongate, at least as long as, usually longer than the combined length of antennomeres VIII–X (ASSING 2016a: figure 43). Median lobe of aedeagus as in Assing (2016a: figures 272–273). Widespread. ............................................................................................................................................................................... castaneus
– Antennomere XI shorter, shorter than the combined length of antennomeres VIII–X (ASSING 2016b: figure 179). Median lobe of aedeagus as in ASSING (2016b: figures 457–458). Vietnam. .................................................... quasar
32. Pronotum strongly transverse, nearly 1.3 times as broad as long and 1.2 times as broad as head; surface without distinct impressions (except for the usual postero-median impression); punctation dense and rather coarse (ASSING 2017: figure 68). Abdominal tergite VI reddish or brown with reddish margins (ASSING 2017: figure 102). Median lobe of aedeagus with conspicuously short ventral process (ASSING 2017: figures 203–204). Thailand. .............. brevilobatus
– Pronotum less transverse, 1.15–1.20 times as broad as long; surface smooth or uneven. Abdominal tergites VI reddish and VII–VIII extensively infuscate. .................................................................................................................. 33
33. Pronotum with uneven surface; punctation conspicuously irregularly distributed and situated in more or less pronounced impressions (ASSING 2017: figure 67). Antennae more slender; antennomere XI elongate, approximately as long as the combined length of VIII–X (ASSING 2017: figures 30–31). Median lobe of aedeagus as in ASSING (2017: figures 198–199). Thailand; Laos. ....................................................................................... novinversus
– Pronotum with smooth surface; punctation moderately irregularly distributed (ASSING 2016a: figure 172). antennae less slender; antennomere XI shorter, barely as long as the combined length of IX and X (ASSING 2016a: figure 173) Median lobe of aedeagus as in ASSING (2016a: figures 231–232). Widespread. ................. bettotanus
34. Abdomen predominantly reddish, sometimes with tergite VI and the anterior portion of tergite VII more or less distinctly infuscate. ........................................................................................................................................................... 35
– Abdomen predominantly black. ...................................................................................................................................... 40
35. Small species of variable coloration; length of forebody 2.1–2.4 mm. Antennomere XI elongate, at least as long as the combined length of antennomeres VIII–X (ASSING 2017: figures 26, 39). Forebody with fine punctation. Median lobe of aedeagus as ASSING (2017: figures 222–223, 234–235). Widespread. ................................. gratellus
– Larger species; length of forebody> 2.5 mm. Antennomere short and of conical shape, shorter than the combined length of IX and X. Body with long pubescence. Species of the Z. hirtus group. ..................................................... 36
36. Forebody dark-brown to black (Fig. 33). Body of larger average size; length of forebody 3.0– 3.5 mm. Abdomen with more extensive and coarser non-setiferous punctation on tergites VI and VII (Fig. 48). Median lobe of aedeagus larger, 0.83–0.90 mm long, and shaped as in Figs 90–91, 93–94. Peninsular Malaysia. ................................. hlavaci
– Forebody reddish to dark-brown. Body of smaller average size, 2.6–3.2 mm. Abdomen with finer and less extensive non-setiferous punctation on tergites VI and VII. Median lobe of aedeagus <0.80 mm long and of different shape. .............................................................................................................................................................................................. 37
37. Slightly larger species; length of forebody 3.0– 3.2 mm. Abdominal tergite VI infuscate. Median lobe of aedeagus very broad in ventral view (ASSING 2017: figures 229–230). Borneo. ........................................................ parahirtus
– Smaller species; length of forebody 2.6–3.1 mm. Abdominal tergite VI not distinctly infuscate. Median lobe of aedeagus more slender in ventral view. .......................................................................................................................... 38
38. Ventral process of aedeagus distinctly angled subapically in lateral view (Figs 99–100). Peninsular Malaysia. ....... ..................................................................................................................................................................................... lunatus
– Ventral process of aedeagus not angled subapically in lateral view. Sunda Islands. ................................................. 39
39. Aedeagus with more slender ventral process both in lateral and in ventral view and with more prominent crista apicalis (Figs 73–74). Java. ................................................................................................................................. flavorufus
– Aedeagus with less slender ventral process and with broader, less prominent crista apcialis (Figs 63–64). Borneo. ............................................................................................................................................................................ matangensis
40. Antennomere XI elongate, approximately as long as the combined length of antennomeres VIII–X. Pronotum rather small in relation to head, only slightly broader than head. .............................................................................. 41
– Antennomere XI shorter, approximately as long as the combined length of antennomeres IX–X. Pronotum relatively larger, much broader than head. ..................................................................................................................................... 42
41. Antennae more slender (ASSING 2017: figures 28–29). Pronotum with very uneven surface; punctation strongly irregular and situated in more or less pronounced impressions (ASSING 2017: figure 65). Male tergite VIII with four blunt projections posteriorly (ASSING 2017: figure 196). Median lobe of aedeagus as in ASSING (2017: figures 191–194). Widespread (ASSING 2017: map 6). .................................................................................................. proximus
– Antennae less slender (ASSING 2017: figure 33). Pronotum without impressions and with less irregularly distributed punctation (ASSING 2017: figure 69). Male tergite VIII only with a median pair of more acute projections posteriorly (ASSING 2017: figure 206). Median lobe of aedeagus as in ASSING (2017: figures 208–211). Thailand. ....................................................................................................................................................... parvicollis
42. Body rather large (length of forebody 3.4–3.7 mm) and of robust shape (ASSING 2015: figure 15). Antennae long (2.7–2.9 mm) and massive (ASSING 2015: figure 16). Elytra bicoloured with the anterior third reddish-yellow and the posterior two-thirds black (ASSING 2015: figure 15). Median lobe of aedeagus as in ASSING (2015: figures 33–34). North Vietnam. ............................................................................................................................................... fansipanicus
– Body less robust and mostly smaller. Antennae less massive, slender in species with antennae of similar length. Elytra often bicoloured, but either more extensively reddish-yellow with infuscate postero-lateral portions or blackish with only the humeral portions reddish or reddish-yellow. ......................................................................... 43
43. Species of more slender habitus (ASSING 2016a: figure 81). Antennae more slender with antennomere IV oblong and antennomere X less than 1.5 times as broad as long (ASSING 2016a: figure 24). Punctation of pronotum and elytra moderately dense (ASSING 2016a: figure 81). Median lobe of aedeagus as in Figs 78–79 and ASSING (2016a: figures 221–222). China, Hong Kong, Laos. ................................................................................................. notaticornis
– Body less slender and with a relatively larger pronotum. Antennae less slender; antennomere X at least 1.5 times as broad as long and antennomere IV usually as long as broad or weakly transverse. Punctation of pronotum and elytra mostly denser. ......................................................................................................................................................... 44
44. Ventral process of aedeagus very short in relation to basal capsule (Figs 87–88). Pronotum with maximal width near anterior angles, slightly more strongly tapering posteriorly. Laos. .................................................. parvilobatus
– Aedeagus with distinctly longer ventral process. Pronotum with lateral margins more evenly convex in dorsal view. .............................................................................................................................................................................................. 45
45. Median lobe of aedeagus with apically longer and more acute ventral process and with longer crista apicalis in lateral view (ASSING 2016a: figures 215–216). China: Yunnan; Thailand. .............................................. caloderoides
– Median lobe of aedeagus with apically shorter and less acute ventral process and with shorter crista apicalis in lateral view. ......................................................................................................................................................................... 46
46. Ventral process of aedeagus basally broader in ventral view (Figs 70–71). Elytra practically completely black; anterior margin only very narrowly reddish-yellow (Fig. 25). Tergite VIII anteriorly with longitudinal striae (Fig. 39). Java. ................................................................................................................................................................................ latibasalis
– Ventral process of aedeagus more slender in ventral view (Figs 76–77 and ASSING 2016a: figures 193–194). Elytra mostly more extensively reddish-yellow (ASSING 2016a: figure 66). China, Laos, Vietnam. ............................... wei
description: Published as part of Assing, Volker, 2017, On Zyras sensu strictu in the East Palaearctic and Oriental regions III, with a focus on the Southeast of Continental Asia and the Sunda Islands (Coleoptera: Staphylinidae: Aleocharinae: Lomechusini), pp. 213-246 in Beiträge Zur Entomologie = Contributions to Entomology 67 (2) on pages 215-220, DOI: 10.21248/contrib.entomol.67.2.213-246, http://zenodo.org/record/5742339