Pseudastenus oculatus Irmler

Busanello, Dilson G. C., Irmler, Ulrich & Caron, Edilson, 2020, Revision of Pseudastenus Bernhauer, synonym with Xenasterides Newton and six new species (Coleoptera, Staphylinidae, Paederinae), Zootaxa 4755 (1), pp. 139-154: 149

publication ID

publication LSID


persistent identifier

treatment provided by


scientific name

Pseudastenus oculatus Irmler

sp. nov.

Pseudastenus oculatus Irmler   , sp. nov.

Figs. 43 View FIGURES 40–45 , 52 View FIGURES 48–54

Material examined. Holotype. Male, dissected. Deposited in INPA, labeled as holotype by Irmler. Brazil, Manaus, Lg. Janauarí, 03.1972, leg. U. Irmler.   Paratypes. 1 female, labeled as paratype by Irmler. Brazil, AM   , Rio Solimões, Ilha Marchanteria (59°58’W, 3°15’S), Várzea, 4.2.1981, leg. J. Adis ( UIC) GoogleMaps   ; 1 female, Brazil, São Paulo de Olivença, Lg. Amataura, 8.1961, leg. Fittkau ( UIC)   .

Diagnosis. P. oculatus   mostly resembles P. latus   in the size of the eyes and coloration but differs by the shape of sclerites of the aedeagus.

Description. Body length: 3.35 mm. Coloration: head dark brown with clypeus yellowish; pronotum light brown to yellowish; elytra dark brown, nearly black in anterior half, more yellowish in posterior half; abdomen dark brown to nearly black with posterior margin of segments yellowish; legs and antennae yellow. Head 0.43 mm long, 0.48 mm wide; eyes large and prominent; 0.33 times as long as total length of head; 0.87 times as long as postocular length; sides approximately parallel; posterior margin straight; slightly depressed on central vertex in front of neck. Pronotum 0.43 mm long, 0.48 mm wide; widest close to anterior angles; anterior margin slightly curved; posterior margin less curved than anterior margin; sides converging posteriad Elytra 0.57 mm long, 0.55 mm wide; 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 triangularly emarginate; suture 0.82 times as long as lateral side; microtuberculate punctation larger than on head and pronotum; with yellow pubescence pointing posteriad; posterior edge with fringe of short dark setae; surface matt. Abdomen with dense punctation; long pubescence pointing posteriad. Aedeagus elongate; 0.51 mm long; approximately four times as long as wide; subparallel; slightly convergent to apex; sclerites with broad base and apical hook; short, 0.11 mm long ( Fig. 52 View FIGURES 48–54 ).

Etymology. The species name derives from the Latin word “oculatus” meaning concerning eyes, and refers to the large eyes.

Geographical records. The specimens are collected from different places of the Várzea of the Rio Solimões, Amazonas ( Brazil).

Biological notes. P. oculatus   was collected from the litter layer of Várzea forests.


Instituto Nacional de Pesquisas da Amazonia


Australian Museum