Pseudastenus plaumanni
Creators: name: Busanello, Dilson G. C.
name: Irmler, Ulrich
name: Caron, Edilson
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Staphylinidae
Pseudastenus
Pseudastenus plaumanni

description: Pseudastenus plaumanni (Bierig, 1939)
Figs. 1–35, 37, 39, 46–47
Xenaster plaumanni Bierig, 1939: 179 (original description, type locality: “ Brasil, Nova Teutonia”). Xenasterides plaumanni: Newton, 2017: 19 (generic name replaced).
Type material examined. Lectotype herein designated (Fig. 37, 39). Male, dissected, deposited in FMNH, Brasil, Nova Teutonia. In the original description Bierig (1939) did not specify the number of specimens but mentioned that the male was unknown. The type deposited in FMNH is a male and it was labelled as lectotype.
Additional materia l. PERU: 1 specimen from Huanuco (UIC); BRAZIL: 2 specimens from Goiás (MZSP), 2 specimens from Distrito Federal (MZSP), 1 specimen from Paraná (DZUP), 37 specimens from Santa Catarina (FMNH); ARGENTINA: 6 specimens from Missiones (FMNH), 10 specimens from Chaco (FMNH).
Diagnosis. P. plaumanni belongs to the species group with developed hind wings and elytra longer than wide. Within this species group, it resembles P. latus in coloration and length of eyes. However, in P. plaumanni the apical sclerites of the aedeagus are entirely narrow and S-shaped (Figs. 46, 47).
Description. Body length: 3.38 mm. Coloration: head, pronotum and appendices yellowish brown, head slightly darker and with lighter V-shaped pattern on head in some specimens; basal half of elytra dark brown; apical half yellowish brown; abdomen dark brown, slightly darker than basal half of elytra. Head 0.45 mm long, 0.51 mm wide; eyes slightly prominent; between 0.26 and 0.29 times as long as total length of head; between 0.52 and 0.63 times as long as postocular length; approximately parallel; posterior margin straight; depressed on central vertex in front of neck. Pronotum 0.44 mm long, 0.50 mm wide; widest close to anterior angles; anterior margin slightly curved; posterior margin straight; sides converging posteriad. Elytra 0.53 mm long, 0.50 mm wide; conspicuously longer than pronotum, but slightly narrower; sides slightly convexly curved; widest in the middle; humeral angles rounded and obtuse, but conspicuously developed; hind wings developed; posterior angles nearly rectangular; posterior margin emarginate; suture 0.86 times as long as lateral side; microtuberculate punctation larger than on head and pronotum; with yellow pubescence pointing posteriad, longer than head and pronotum; posterior edge with fringe of sparse robust setae. Abdomen with dense punctation; with yellow pubescence pointing posteriad; pubescence conspicuously longer than on the rest of body. Aedeagus elongate; 0.55 mm long; near 4.25 times as long as wide; parameres indistinguishable; conspicuous basal sclerite; barely S-shaped apical sclerites, 0.11 mm long; ejaculatory duct with two trifurcate sclerites (Figs. 46, 47).
Taxonomic notes. The type specimen of P. plaumanni, including aedeagus, was in bad conditions. Figure 46 shows the aedeagus of the lectotype, whereas Fig. 48 shows the aedeagus of a male collected near the type locality. In Figs. 46 and 47 the S-shaped apical sclerites “b” is considered as diagnostic character for P. plaumanni.
Geographical records. Pseudastenus plaumanni is known from Brazil (north of Goiás, Distrito Federal, Paraná and Santa Catarina), from Argentina (Chaco and Missiones), and from Peru (Huanuco).
Biological notes. Specimens of Pseudastenus plaummani were collected in leaf litter and decaying wood.
description: Published as part of Busanello, Dilson G. C., Irmler, Ulrich & Caron, Edilson, 2020, Revision of Pseudastenus Bernhauer, synonym with Xenasterides Newton and six new species (Coleoptera, Staphylinidae, Paederinae), pp. 139-154 in Zootaxa 4755 (1) on pages 142-145, DOI: 10.11646/zootaxa.4755.1.6, http://zenodo.org/record/3724291