Eleusis fenestrata SHARP, 1887

Irmler, Ulrich, 2017, The Neotropical species of the genus Eleusis LAPORTE, 1835 with description of the new genus Eleusima (Coleoptera: Staphylinidae: Osoriinae), Beiträge Zur Entomologie = Contributions to Entomology 67 (2), pp. 275-318 : 297

Eleusis fenestrata SHARP, 1887

Figs 21 A-C, 30D

Eleusis fenestrata SHARP, 1887: 730

Type material: male, Holotype: Guatemala: Cerro Zunil ,

leg. Champion ( BMNH).

Diagnosis: Eleusis fenestrata resembles E. adusta in the dark colouration with light reddish-yellow spot on the elytra and the deep punctation. E. fenestrata is smaller and the central prominence at the posterior margin of the pronotum is absent. Moreover, the microsculpture is more regularly longitudinal than in E. adusta . The aedeagus of E. fenestrata is distinctly thicker and curved. In this respect, it can be easily differentiated from similarly coloured E. bicolor specimens. E. bicolor specimens of similar colouration can be separated from E. fenestrata by the punctation of the head. Whereas E. bicolor has coarse punctures on the vertex compared to clypeus, head punctation of E. fenestrata is uniform on vertex and clypeus.

Description: Length: 4.7 mm. Colouration: black; elytra with large humeral yellowish spot; legs and antennae dark brown.

Head: 0.75 mm long, 0.75 mm wide; eyes not prominent; temples slightly longer than eyes; approximately parallel; preocular sides short and parallel; anterior margin of clypeus narrowed to central slightly prominent part; supraocular groove parallel to sides; punctation deep and dense; size of punctures irregularly large; interstices between punctures irregularly wide; on average, interstices between punctures as wide as to twice as wide as diameter of punctures; setiferous puncture at each end of supraocular groove; elongate microsculpture deep; longitudinally striate; interstices between striae shiny.

Antennae as long as head and half of pronotum combined; first antennomere thicker than following antennomeres; 1.5 times as long as second; third slightly longer than second, but shorter than first; following antennomeres decreasing in length and increasing in width; fourth antennomere longer than wide; tenth quadrate; fourth to eleventh antennomere pubescent; all antennomeres with apical setae.

Pronotum: 0.66 mm long, 0.76 mm wide; widest close to anterior angles; sides in anterior half approximately parallel; in posterior half continuously narrowed to posterior angles; posterior angles obtuse; at anterior angles with short groove; punctation as deep and dense as on head; few setiferous punctures in grooves at anterior angles; few additional setiferous punctures along lateral margin; at beginning of posterior convergence, one setiferous puncture deeply impressed; elongate microsculpture slightly less deep than on head; longitudinally striate; surface moderately shiny.

Elytra: 0.83 mm long, 0.79 mm wide; sides approximately parallel; humeral angles nearly rectangular; posterior angles rounded; punctation as deep and dense as on head and pronotum; one setiferous puncture in central position on each side of suture; few additional setiferous punctures along lateral margin; longitudinal microsculpture as deep and dense as on head and pronotum; surface slightly shiny.

Abdomen with moderately dense punctation; on each segment with transverse row of setiferous punctures; microsculpture deep; transversely striate.

Aedeagus stout and thick; in lateral aspect, with broad apex; curved; in ventral aspect, parallel with widely rounded apex; numerous sensillae on apical central lobe; paramere slightly shorter than central lobe; sinuate; apical transparent lobe moderately widened and slightly curved; with distinct apical seta and few minute sensillae.

Figures

Fig. 18–23: Eleusis platysoma (18), E. bicolor (19), E. struyvei (20), E. fenestrata (21), E. rufula (22), E. adusta (23): aedeagus in lateral (A) and ventral (B) view, antenna (C), head (D), colouration of elytra (E); scale bar A, B: 0.1 mm, C: 0.2 mm, D, E: 1.0 mm.