Osoriellus trinitatis ( BLACKWELDER, 1943 ) Irmler, 2014

Irmler, Ulrich, 2014, The Neotropical species of the genus Osoriellus FAGEL, 1959 (Coleoptera: Staphylinidae: Osoriinae), Beiträge Zur Entomologie = Contributions to Entomology 64 (2), pp. 231-354 : 308-310

Osoriellus trinitatis ( BLACKWELDER, 1943) new combination

( Figs 103 A-C, 123B)

Osorius trinitatis BLACKWELDER, 1943: 199

Type material examined: Trinidad: Arima, 12 mi. N, female, 23.06.1935, leg. G. Weber (paratype in NMNH)

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Further material examined: Trinidad: Arima (61°16'W, 10°37'N), Blanchisseuse, rotten log on ground, 550 m elevation, male, female, 05.01.1961, leg. T. Clay ( BMNH) ; Aripo (61°15'W, 10°42'N) N. Range, cloud forest, debris among aerial palm roots, 920 m elevation, 2 females, 21.01.1961, leg. T. Clay ( BMNH) ; Panama: La Fortuna, Continental Divide Trail (82°12'0"W, 8°46'0"N); berlesate forest litter, 1200 m elevation, 2 males, 5 females, 9.6.1995, leg. R. Anderson, #PAN2A95 10F ( KNHM, UIC) ; Costa Rica: Heredia, 10 km SE La Virgen (84°05'W, 10°20'N), 450-550 m elevation, female, 17.- 21.3.2003, leg. R. Anderson ( KNHM) ; Heredia, La Selva, 3.2 km SE Puerto Viejo, 100 m elevation, flight intercept trap, female, 17.3.1992, leg. W. Bell ( KNHM) ; Guanacaste, Guanacaste Conservation Area, Patilla Field Station , sampled in cloud-wet montane trans. litter, 1000 m elevation, 1 male, 2 females, 14.2.1996, leg. R. Anderson ( KNHM, UIC) ; 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), 950 m elevation, female, 14.7.1997, leg. R. Anderdson ( KNHM) ; Peru: Loreto, Campamento San Jacinto (75°51'77" W, 2°18'75" S), 175-215 m elevation, rainforest berlese, female, 6.7.1993, leg. R. Leschen ( KNHM) ; Loreto, 1.5 km N Teniente Lopez (76°06.92'W, 2°35.66'S), 210-240 m elevation, nr. Ganoderma, female, 21.7.1993, leg. R. Leschen ( KNHM) ; Bolivia: Cochabamba, 117 km E Yungas, Lagunitas (65°40'57"W, 17°6'22"S), flight intercept trap, female, 1.- 6.2.1999, leg. F. Genier ( KNHM) .

Key to the remaining species

1. Smaller than 6.0 mm. .......................................................................................................................................................... 7

- Longer than 6.5 mm. ......................................................................................................................................................... 17

2. Eyes thick and nearly semicircular. ................................................................................................................................... 3

- Eyes less thick, only slightly prominent or not prominent. ........................................................................................... 4

3. Punctation of pronotum sparse, but punctures very large, surface with microsculpture, sides only slightly narrowed to posterior angles, lateral and posterior margin of pronotum and elytra yellowish brown. ......... O. orbiculatus n. sp.

- Punctation of pronotum denser, punctures smaller, surface without microsculpture, sides evenly narrowed to posterior angles in smooth curve, colouration dark brown. ................................................................ O. opticus n. sp.

4. Protibia with extremely long digits, WLR smaller than 0.35. ....................................................................................... 5

- Protibia with moderately long digits; WLR higher than 0.60. .........................................................................................

5. Smaller than 4.0 mm, anterior angles of pronotum not produced to acute teeth, posterior angles of pronotum rounded. ................................................................................................................................................... O. digitatus n. sp.

- Longer than 5.0 mm, anterior angles produced to distinct acute teeth, posterior angles obtuse, but distinctly angulate. ................................................................................................................................................................ O. acutus n. sp.

6. At least 4.0 mm long. .......................................................................................................................................................... 8

- Smaller than 3.5 mm. .......................................................................................................................................................... 7

7. Setiferous punctation of pronotum dense and coarse, interstices between punctures distinctly shorter than diameter of punctures. .................................................................................................................... O. carinicollis ( NOTMAN, 1925)

- Setiferous punctation of pronotum sparser and finer, interstices between punctures as wide as diameter of punctures. ............................................................................................................................ O. trinitatis ( BLACKWELDER, 1943)

8. Shoulders with rectangular angle. ..................................................................................................................................... 9

- Shoulders rectangular, but rounded. .............................................................................................................................. 11

9. Black, sides of pronotum evenly narrowed to posterior angles. .................................................. O. rectangulus n. sp.

- Light reddish brown, sides of pronotum slightly emarginate in middle, nearly parallel in posterior half. ........... 10

10. Head with weak microsculpture, surface moderately shiny, pronotum without microsculpture or only with remains of microsculpture, surface shiny. ........................................................................................................... O. rufescens n. sp.

- Head with dense and deep microsculpture, surface matt, pronotum with dense, but weak microsculpture, surface moderatly shiny. ............................................................................................................................................ O. loreti n. sp.

11. At least 5.3 mm long. ........................................................................................................................................................ 15

- Smaller than 4.8 mm. ........................................................................................................................................................ 12

12. Pronotum with deep and dense microsculpture, surface matt. .......................................................... O. adustus n. sp.

- Pronotum without or with weak microsculpture, surface shiny. ................................................................................ 13

13. Head with dense microsculpture, surface with iridescent shine. ........................... O. weberi ( BLACKWELDER, 1943)

- Head without or with weak microsculpture, surface without iridescent shine. ....................................................... 14

14. Light brown, surface of pronotum polished and shiny. ....................................................................... O. lescheni n. sp.

- Dark brown, surcface of pronotum with weak microsculpture, moderately shiny. ..................... O. infuscatus n. sp.

15. Pronotum with dense and finer punctation, without impunctate midline. ...... O. cordovensis ( BERNHAUER, 1910)

- Pronotum with sparser or coarser punctation and with wide impunctate midline. ................................................ 16

16. Light red, angles of clypeus produced to acute teeth, punctation of pronotum sparser, interstices between punctures tree to four times as wide as diameter of punctures ................................................ O. notmani ( DARLINGTON, 1937)

- Dark brown, angles of clypeus produced to granules, punctation of pronotum denser, two times as wide as diameter of punctures. .............................................................................................................. O. neotropicus ( BERNHAUER, 1908)

17. Sides of pronotum strongly narrowed in distinct curve to posterior angles, pronotum with weak or without microsculpture, surface shiny or polished. .............................................................................................................................. 19

- Sides evenly and straightly narrowed to posterior angles; pronotal shap trapezoidal, pronotum with dense and deep microsculpture, surface matt. .......................................................................................................................................... 18

18. Anterior angles of clypeus only produced short granules, microsculpture of pronotum dense, surface matt. ......... ................................................................................................................................................................. O. opacinotus n. sp.

- Anterior angles of clypeus produced to short and acute teeth, microsculpture of pronotum less dense, surface moderately matt. ....................................................................................................................................... O. sticticus n. sp.

19. Punctation of pronotum sparse, interstices between punctures at least twice as wide as diameter of punctures. .... ................................................................................................................................... O. sexpunctatus ( BERNHAUER, 1912)

- Punctation of pronotum denser, interstices between punctures as wide as diameter of punctures or slightly wider. ................................................................................................................................................... O. germanus ( SHARP, 1887)

Diagnosis: Among the species with digitate protibia and setiferous pronotal punctation, the species resembles O. carinicollis in size and shape of the pronotum, but it has a distinctly finer punctate pronotum. The aedeagus is thick and obtuse at apex, whereas it is thin and acute in O. carinicollis .

Description: Length: 3.1 mm. Colouration: Brown; pronotum and elytra at shoulders reddish; legs, antennae, and anterior margin of clypeus yellow.

Head: 0.37 mm long, 0.58 mm wide; eyes not prominent and as long as temples; sides of fore-head sinuate; anterior edge of clypeus even; without lateral granules; width of anterior edge smaller than width of head in front of eyes; on vertex, setiferous punctation dense and coarse; interstices between punctures half as wide as diameter of punctures; irregular midline impunctate; impunctate midline without microsculpture; surface polished and shiny; on punctate areas of vertex with remains of microsculpture; surface matt or slightly shiny.

Antennae short; slightly longer than head; second antennomere thick and oval; distinctly longer than conical third antennomere; following 3 antennomeres slightly increasing in width and distinctly wider than long; antennomeres 7 to 11 distinctly thicker than preceding antennomeres; antennomere 10 only slightly wider than long.

Pronotum: 0.53 mm long, 0.56 mm wide; widest at anterior angles; sides evenly convergent to posterior widely rounded angles; lateral margin fine; in dorsal aspect, visible throughout its total length; setiferous punctation distinctly finer and sparser than on head; interstices between punctures approximately as wide as diameter of punctures; between normal punctures with sparse micropunctation and weak remains of microsculpture; surface mostly polished and shiny.

Elytra: 0.68 mm long, 0.59 mm wide; ground-sculpture deep and coarse; coarse setiferous punctation nearly invisible in ground-sculpture; surface matt.

Abdomen with coarse setiferous punctation; similar to elytral punctation; surface matt, except impunctate shinier midline.

Protibia: 0.30 mm long, 0.10 mm wide; on outer edge with 8 long spines; 3 apical spines inserted on short digits; WLR: 1.00; posterior face covered with sparse setae; in posterior aspect, inner emargination distinctly visible; in middle, partly covered by posterior inner edge.

Aedeagus with thick apical lobe ending in widely rounded obtuse apex; along inner edge with groups of several sensillae.

Figures

Fig. 103-108: Remaining-species-group: Osoriellustrinitatis (103), O. carinicollis (104), O. sticticus (105), O. acutus (106), O. orbiculatus (107), O. adustus (108); antenna (A), protibia (B), aedeagus in lateral aspect (C); scale bar: 0.1 mm.