Pseudastenus oculatus Irmler, 2020

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

Pseudastenus oculatus Irmler , sp. nov.

Figs. 43 , 52

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) ; 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 ).

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.

Figures

FIGURES 40–45. Dorsal view. 40. Pseudastenus ribeirocostae sp. nov.; 41. P. ferrugineus sp. nov.; 42. P. latus sp. nov.; 43. P. oculatus sp. nov.; 44. P. amazonicus sp. nov.; 45. P. schubarti sp. nov. Scale bars: 2 mm.

FIGURES 48–54. Aedeagus of Pseudastenus, dorsal and lateral view, respectively, figures 51–54 including microscopic detail of basal slerites. 48. P. ribeirocostae sp. nov.; 49. P. ferrugineus sp. nov.; 50. P. latus sp. nov.; 51. P. barretoi; 52. P. oculatus sp. nov.; 53. P. amazonicus sp. nov.; 54. P. schubarti sp. nov. Scale bar: 0.3 mm.