Pseudastenus Bernhauer, 1933

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 : 141-142

Key to species of Pseudastenus Bernhauer

1. Elytra shorter than pronotum, 0.9 times as long as pronotum, sides divergent to posterior margin, widest at posterior margin. ................................................................................................... 2

- Elytra longer than pronotum, ranging between 1.1 and 1.4 times as long as pronotum, sides slightly curved, widest in front of posterior margin...................................................................................... 4

2. Eyes reduced, approximately only 0.20 times as long as total length of head; postocular length more the two times longer than eyes; elytra unicolored or not conspicuously bicolored........................................................ 3

- Eyes less reduced, approximately 0.30 times as long as total length of head; postocular length only 1.6 times as long as eyes; elytra conspicuously bicolored, with distinct black anterior half......................................... P. barretoi

3. Eyes slightly larger; postocular sides approximately parallel; elytra slightly bicolored, anterior half of elytra indistinctly darker than posterior half.......................................................................... P. ribeirocostae

- Eyes slightly smaller; postocular sides divergent; elytra unicolored yellow................................ P. schubarti

4. Eyes large, 0.33 times as long as total length of head; postocular length equal to eye length................... P. oculatus - Eyes smaller, between 0.24 and 0.31 times as long as total length of head; postocular length distinctly longer than eye length ................................................................................................... 5

5. Pronotum light brown; elytra with basal half darker than apical half (in some specimens not so conspicuous)............. 6

- Pronotum rust brown to reddish; elytra with basal two-thirds darker than apical onethird................... P. ferrugineus

6. Larger, at least 3.00 mm long; elytra bicolored, dark brown to black in anterior half and light brown in posterior half; aedeagus with apical sclerites of internal sac not elongate............................................................. 7

- Smaller, 2.20 mm long; elytra unicolored light brown; aedeagus with apical sclerites of internal sac elongate and straight............................................................................................ P. amazonicus

7. Head light brown; median lobe of aedeagus with apical sclerites entirely narrow and S-shaped ( Figs. 46–47 ).... P. plaumanni

- Head dark brown; median lobe of aedeagus with apical sclerites broad on the basal half and not S-shaped ( Fig. 50 )... P. latus

Figures

FIGURES 46–47. Aedeagus of Pseudastenus plaumanni. 46. Dissected from the lectotype (FMNH), dorsal view. 47. Dissected from a specimen collected in the type locality, dorsal and lateral view, respectively. Details: a, basal sclerite; b, apical sclerite; c, basal sclerite of the ejaculatory duct; d, apical sclerite of the ejaculatory duct. Scale bars: 0.2mm.

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.