Diochus ashei, Irmler, 2017

Irmler, Ulrich, 2017, A review of the Neotropical genus Diochus ERICHSON, 1840 (Coleoptera: Staphylinidae: Staphylininae), Beiträge Zur Entomologie = Contributions to Entomology 67 (1), pp. 1-62 : 5

Diochus ashei spec. nov.

urn:lsid:zoobank.org:act:949EFF27-4323-46C9-8F5D-F4731958CA14

Figs 6A–C , 38C , 41D

Type material: male Holotype: Peru: Tambopata Prov., Madre de Dios Dpto., 15 km NE Puerto Maldonado, Reserva Cuzco Amazónico (69°03'W, 12°33'S), 200 m elevation, Plot #Z1U19, collected by flight intercept trap, 13.7.1989, leg. J.S. Ashe & R.A. Leschen, #484, ( KNHM).

Paratypes: 1 female, 1 male, with same data as holotype ( KNHM, UIC) .

Diagnosis: According to the aedeagal structure, the species is related to D. longicornis SHARP, 1876 . Regarding the small size, it resembles D. unicolor and D. adisi . It can be distinguished from D. unicolor by the larger eyes. In this respect, it resembles D. adisi . Differentiation to D. adisi are listed there. D. ashei also resembles D. tricolor by the light yellow pronotum and the darker head and elytra. Beside the differences in the aedeagus, the punctation of the head is denser in D. tricolor than in D. ashei . Whereas in D. tricolor the clypeus is densely punctate, it is impunctate in D. ashei . The females of both species are distinguished also by the shape of the spermatheca that has irregular coils in D. tricolor , but circle coils in D. ashei .

Description: Length: 3.0 mm. Colouration: light brown; fifth and sixth abdominal segment slightly darker; elytra light brown; head dark brown; pronotum light yellow; legs and antennae yellow.

Head 0.41 mm long, 0.35 mm wide; eyes slightly prominent; EL: HL = 0.29; temples 1.9 times as long as eyes; slightly divergent to posterior angles; PW: EW 1.33; posterior angles shortly rounded to straight posterior margin; neck extremely narrow; 0.25 times as wide as width at posterior angles; setiferous punctation sparse; adjacent to wide impunctate midline with row of four punctures and second irregular supraocular row of punctures; temples with denser punctation; microsculpture weak and indistinct; on clypeus approximately isodiametric; on vertex transversely striate; surface slightly shiny.

Antennae nearly as long as head and pronotum combined; first antennomere thicker and longer than following antennomeres; elongate second and third antennomere conical and 1.8 times as long as apical width; length of following antennomeres decreasing; fourth antennomere slightly longer than wide; tenth antennomere 1.5 times as wide as long; all antennomeres pubescent and with few apical setae.

Pronotum 0.51 mm wide, 0.37 mm wide; sides widest in anterior third; strongly narrowed to neck; slightly narrowed to posterior angles; posterior angles widely rounded; lateral margin fine; in dorsal aspect, visible in posterior half; setiferous punctation sparse; along wide impunctate midline with row of three pairs of punctures; interstice between first pair of punctures nearly twice as wide as between two posterior pairs; few additional punctures laterad; several setiferous punctures along lateral margin; without microsculpture; surface polished; with sparse micro-punctation.

Elytra 0.50 mm long, 0.54 mm wide; sides divergent to posterior angles; at posterior angles 1.3 times as wide as at shoulders; shoulders obtuse; posterior margin slightly triangularly emarginate; setiferous punctation in irregular rows of four to five punctures; weakly coriaceous ground sculpture; surface less shiny than head and pronotum.

Abdomen densely pubescent.

Aedeagus with thick, nearly globular seminal vesical; 0.4 times as long as central lobe; basal inner duct looped; apical duct with two large coils; paramere shorter than central lobe; not widened at apex; slightly curved and with three setae shortly in front of apex; two long setae and one slightly shorter seta.

Spermatheca globular, 0.15 mm diameter, bursa copulatrix in central position to coiled duct; coiled duct with few coils.

Etymology: The species name honours J.S. Ashe, one of the collectors, who extensively collected and worked on Neotropical rove beetles and passed to early.

Figures

Figs 41: Fore-bodies of Diochus longicornis (A), D. tarsalis (B), D. adisi (C), D. ashei (D), D. guianensis (E), D. unicolor (F), D. inornatus (G), D. hanagarthi (H); scale bar: 0.5 mm.

Figs 6–9: Diochus longicornis-group: Diochus ashei (6), D. unicolor (7); Diochus inornatus-group: D. inornatus (8), D. hanagarthi (9); aedeagus (A), paramere (B) and antenna (C); scale bar: A, B: 0.1 mm, C: 0.2 mm.

Fig. 38: Spermathecae of Diochus longicornis-group: D. longicornis (A), D. tarsalis (B), D. ashei (C), D. guianensis (D), D. unicolor (E); Diochus inornatus-group: D. inornatus (F), D. hanagarthi (G), D. antennalis (lateral aspect H), D. hermani (I), D. hibbsi (J), D. newtoni (K), D. novus (L); scale bar: 0.1 mm.