Osoriellus trapezoides Irmler 2014, n. sp.
Creators: name: Irmler, Ulrich
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Staphylinidae
Osoriellus
Osoriellus trapezoides

description: Osoriellus trapezoides n. sp.
(Figs 82 A-C, 101A)
Type material: Holotype, male: Costa Rica: Puntarenas Prov., Altamira Biol. Sta. (83°00.49'W, 09°01.76'N), 1510-1600 m elevation, collected by flight intercept trap CR1AFH04144, 4.-7.VI.2004, leg. J.S. Ashe, Z. Falin, I. Hinojosa (KNHM).
Paratype: Costa Rica: Alajuela, E.B. San Ramon, R.B. San Ramon, 27 km N & 8 km W San Ramon (84°35.30'W, 10°13.30'N), male, collected from wet montane forest litter CR1A99-109D, 29.6. – 6.7.1999, leg. R. Anderson (UIC).
Diagnosis: The species is similarly sized as O. debilis, but the shape of the head and pronotum is distinctly different. It can be easily identified by the conspicuous trapezoidal shape of the head.
Description: Length: 5.2 mm. Colouration: Dark brown; elytra reddish brown; legs and antennae lighter brown.
Head: 0.63 mm long, 1.06 mm wide; eyes slightly prominent and slightly longer than temples; sides of fore-head convergent to front angles in slight sinuate curve; close to anterior edge nearly parallel; in dorsal aspect, shape trapezoidal; clypeal angle produced to short granules; anterior edge even; setiferous punctation weak and sparse; near base of antennae impunctate and on supraocular area with denser punctation; on vertex, interstices between punctures wider than diameter of punctures; one supraocular seta and one neck seta longer than normal setation; isodiametric microsculpture extremely weak; surface shiny, nearly polished.
Antennae distinctly longer than head; with oblong second antennomere and conical third antennomere; each longer than wide; following three antennomeres not wider than preceding antennomeres, but approximately quadrate; antennomeres 7 to 11 thicker than preceding antennomeres and also quadrate.
Pronotum: 0.98 mm long, 1.08 mm wide; widest at anterior angles; anterior angles produced to short teeth; sides slightly convergent in anterior two-third; more strongly convergent in posterior third; lateral margin fine; close to anterior angles invisible in dorsal aspect; posterior angles obtuse; smoothly rounded; setiferous punctation deeper and denser than on head; with impunctate midline; 10 punctures in irregular row adjacent to midline; on average, interstices between punctures half as wide as diameter of punctures; few sparser punctate areas in posterior half; between large setiferous punctation with sparse micro-punctation; isodiamteric microsculpture deeper and more distinct than on head; surface shiny, but less shiny than on head.
Elytra: 1.25 mm long, 1.18 mm wide; with coriaceous ground-sculpture; setiferous punctation hardly visible in coarse ground-sculpture; punctures in irregular rows.
Abdomen with setiferous punctation and impunctate midline on tergites II to VII; netlike microsculpture weak; surface shiny.
Protibia: 0.58 mm long, 0.18 mm wide; nearly semicircular; 8 spines on outer edge; WLR: 2.0; in posterior aspect, comb of inner emargination visible throughout its total length; posterior face with moderately dense setation; setae nearly half as long as protibial width.
Aedeagus with smoothly rounded apical lobe ending in obtuse apex.
Etymology: The specific name trapezoides refers to the trapezoidal shape of the head.
description: Published as part of Irmler, Ulrich, 2014, The Neotropical species of the genus Osoriellus FAGEL, 1959 (Coleoptera: Staphylinidae: Osoriinae), pp. 231-354 in Beiträge Zur Entomologie = Contributions to Entomology 64 (2) on page 289, DOI: 10.21248/contrib.entomol.64.2.231-354, http://zenodo.org/record/5461706