Eleusis elongata, Irmler, 2017

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 : 296-297

Eleusis elongata spec. nov.

urn:lsid:zoobank.org:act:

Figs 27 A-C, 31C

Type material: male, Holotype: Costa Rica: Cartago, P.N. Tapanti ( 9°45.41'N, 83°47.5'W), 1150 m elev. flight intercept trap, 17.- 20.7.2000, leg. J. Ashe, R. Brooks, Z. Falin, #CR1ABF00192 ( KNHM). Paratype: Costa Rica: San José, Zuruqui de Moravia , 1600 m elev., malaise trap, female, 1.- 30.8.1995, leg. P. Hanson #CR1H93-9514 ( KNHM) .

Diagnosis: The species is unique regarding its elongate shape. In contrast to all other Eleusis species , E. elongata is not depressed. Concerning the colouration, E. elongata resembles E. bicolor and E. struyvei . The aedeagus, too, resembles that of E. bicolor . The long projecting mandibles with a molar-like tooth at left mandible are also unique for the known Neotropical Eleusis species.

Description: Length: 7.6 – 7.8 mm. Colouration: head and pronotum black; anterior half of elytra orange; posterior half blackish; abdominal segments III-VI yellow, VII and VIII black; legs light brown; antennae dark brown.

Head: 1.34 mm long, 0.93 mm wide; eyes not prominent; temples parallel; extremely long; more than four times as long as eyes; neck nearly as wide as vertex; preocular sides parallel; distinctly longer than eyes; anterior margin of clypeus indistinctly sinuate; central part of clypeus shortly prominent; supraocular groove deep; reaching from anterior edge of eyes to posterior edge of temples; supraocular ridge indistinct; parallel to sides from antennal base to neck; mandibles projecting; as long as distance from anterior margin of clypeus to posterior edge of eyes; left mandible with thick molar tooth; right mandible with acute tooth; punctation deep and irregularly dense; interstices between punctures varying between as wide as diameter of punctures to four times as wide as diameter of punctures; at each end of supraocular groove with setiferous puncture; pair of setiferous punctures on each side of clypeal prominence; elongate indistinct microsculpture; longitudinally striate; surface moderately shiny.

Antennae slightly longer than head; first antennomere thick; not elongate; second antennomere distinctly shorter and narrower; third antennomere slightly longer than second; slightly longer than apical width; following antennomeres increasing in width; fourth antennomere longer than wide; tenth antennomere as long as wide; antennomeres four to eleven pubescent and with long apical setae.

Pronotum: 1.11 mm long, 0.93 mm wide; widest close to anterior angles; slightly narrowed to posterior third; posterior third strongly convergent to posterior angles; posterior margin half as wide as anterior margin; long groove at anterior angles; inner margin bordered by distinct ridge ending at posterior third; second indistinct triangular groove at inner side bordered at lateral side by indistinct ridge; outer ridge and inner ridge running convergent to anterior angles; punctation similar to head punctation; setiferous punctures: in outer groove close to anterior angles, at obtuse angle at beginning of convergence, at inner border of triangular groove at anterior margin; elongate microsculpture weak; longitudinally striate; surface moderately shiny.

Elytra: 1.34 mm long, 1.07 mm wide, sides nearly parallel; humeral angle obtuse; posterior angles nearly rectangular; punctation like that of head and pronotum; on central disc, two pairs of setiferous punctures; additional setiferous punctures along lateral margin; elongate microsculpture weak; longitudinally striate; surface moderately shiny.

Abdomen sparsely and weakly punctured; few setiferous punctures; partly with long setae; at lateral margin; microsculpture transversely striate; weak; surface moderately shiny.

Aedeagus in lateral aspect moderately thick; apex rounded; with indistinct longitudinal and transverse ridges in front of apex; ventral plate with few central sensillae; in ventral aspect, nearly parallel, but slightly widened at middle; apex obtuse; numerous sensillae; paramere slightly shorter than central lobe; with moderately wide apical transparent lobe; few micro-sensillae in transparent lobe; extremely fine setae at apical margin; on scape, few sensillae.

Etymology: The species name derived from the Latin word elongatus meaning elongate and refers to the extreme elongate, slender shape which is untypical for the usually flattened shape of Eleusis species.

Figures

Fig. 24–27: E. peruviana (24), E. panamaensis (25); E. frater (26), E. elongata (27): aedeagus in lateral (A) and ventral (B) view,