Osorius

Irmler, Ulrich, 2010, The Neotropical species of the genus Osorius G - M, 1829 with remarks to the Neotropical Osoriid complex (Coleoptera: Staphylinidae: Osoriinae), Beiträge Zur Entomologie = Contributions to Entomology 60 (2), pp. 363-426 : 370-373

Key to the Neotropical species of Osorius

1. Large species, longer than 12 mm. ...............................................................................B

- Species smaller than 12 mm. ........................................................................................H

2. Front angles of clypeus long and acute ( Fig. 1d ). ............................. O. ater PERTY, 1830

- Front angles of clypeus obtusely prominent (Fig. 23d). ................................................C

3. With numerous supraocular striae and granulate punctures (Fig. 2e). .......................... D

- Without or with only few supraocular striae, but with numerous postocular striae ( Fig. 4e ). ......................................................................................................................F

4 Apical part of aedeagus long and acuminate (Fig. 2c). .................. O. stipes SHARP, 1876

- Apical part of aedeagus shorter and obtuse (Fig. 3c). ...... O. alternans BERNHAUER ,, 1920

5 Surface of elytra with dense coriaceous ground sculpture, punctation within in the coriaceous ground sculpture not visible ( Fig. 39 A ). ......................................................................F

- Surface of elytra with sparse coriaceous ground sculpture, shiny, nearly polished, punctation on all parts clearly visible ( Fig. 39 B ). ...........................................................................G

6. Larger species, at least 14 mm long, clypeus with central prominence, microsculpture of pronotum weak, surface nearly polished. ......................... O. canaliculatus SOLSKY, 1870

- Smaller species of about 13 mm, clypeus without central prominence, microsculpture of pronotum distinct, surface slightly shiny. ................... O. columbinus BERNHAUER ,, 1920

7. Pronotum without depressions in posterior angles. ....... O. intermedius ERICHSON, 1840

- Pronotum with indistinct depressions in posterior angles. ..... O. brasiliensis GUÉRIN, 1829

8. Eyes distinctly prominent (Fig. 8a, 9a). ........................................................................ I

- Eyes not or only slightly prominent (Fig. 10a). .......................................................... 10

9. Larger, 8.0 mm long, 3 rd antennomere twice as long as 2 nd. .......... O. boops SHARP, 1887

- Smaller, 7.0 mm long, 3 rd antennomere not longer than 2 nd. ....... O. affinis SHARP, 1876

10. Small, not longer than 8.0 mm, pronotum relatively long, length: width relationship between 0.87 and 1.1. ............................................................................................................. 11

- Larger than 8.5 mm, pronotum wider, length: width relationship 0.74 – 0.87. .......... 18

11. Pronotum with dense and deep microsculpture, surface matte or slightly shiny ( Fig. 38 D ). ................................................................................................................ 12

- Pronotum with weak microsculpture and micro-punctation ( Fig. 38 C ). ........................ ........................................................................................ O. dentatus BERNHAUER ,, 1920

12. Punctation on pronotum sparse and fine, distance between punctures at least three times wider than diameter of punctures ( Fig. 38 D ). ........................................................... 13

- Punctation on pronotum denser and larger, distance between punctures two times wider than diameter of punctures ( Fig. 38 E ). ...................................................................... 15

13. Microsculpture of pronotum dense, but not deep, surface slightly shiny, head with postocular striae. ......................................................................... O. costaricensis BERNHAUER ,, 1942

- Microsculpture of pronotum dense and deep, surface matte, head without postocular striae. ......................................................................................................................... 14

14. Side of pronotum nearly parallel ( Fig. 36 A ), posterior edge nearly as long as anterior edge, shoulders nearly rectangular. ............................................................. O. verhaaghiverhaaghi sp. n.

- Pronotum slightly, but distinctly narrowed to posterior angels ( Fig. 36 B ), anterior edge about 1.1 times longer than posterior edge, shoulders obtuse, smoothly rounded. ........... ............................................................................................................ O. paganuspaganus sp. n.

15. Clypeus close to the outer obtuse prominence with an additional acute tooth on each side (Fig. 15d). .................................................................................... O. venezuelanusvenezuelanus sp. n.

- Clypeus only with an outer prominence on each side. ................................................ 16

16. Smaller, 6.0 mm; anterior angles of pronotum tooth-like prominent ( Fig. 36 D ), pronotum less narrowed to posterior angles, anterior edge only 1.1 times wider than posterior edge. ................................................................................................... O. pusillus sp. n.

- Larger, 7.4 – 8.0 mm long. ........................................................................................ 17

17. Punctation of pronotum deeper and denser, anterior angles not prominent, larger, 7.8 – 8.0 mm. ............................................................... O. laevicollis BERNHAUER ,, 1908

- Punctation of pronotum slightly sparser and finer, anterior angles prominent, smaller, 7.5 mm. ......................................................................... O. sublaevis BERNHAUER ,, 1920

18. Sides of pronotum in front of posterior angles deeply emarginate (Fig. 19a). .................. .................................................................................. O. sinuatocollis BERNHAUER ,, 1920

- Sides of pronotum only slightly emarginate in front of posterior angles ( Fig. 20a ). ..... 19

19. Pronotum with micro-punctation between the normal larger punctures ( Fig. 38 F ). ... 20

- Pronotum without micro-punctation between the normal larger punctures. .............. 24

20. Pronotum without microsculpture, surface polished. ................................................. 21

- Pronotum with weak microsculpture, surface shiny, but not polished. ....................... 23

21. With numerous supraocular and postocular striae, linear furrow in pronotal midline extending to anterior half (Fig. 21a, 22a). .................................................................. 22

- With few supraocular striae, linear furrow on pronotal midline only in posterior half. .... ................................................................................................................. O. ashei sp. n.

22. Pronotum with irregular punctation and an indistinct transverse depression in the middle. ........................................................................ O. laevigatulus SCHUBERT, 1911

- Pronotum regularly punctate and without transverse depression. .................................... ..................................................................................... O. wasmanni BERNHAUER ,, 1920

23. Head with numerous granulate punctures and supraocular and postocular striae. ........... .................................................................................... O. peruvianus BERNHAUER ,, 1908

- Head without granulate punctures and supraocular striae, only with few postocular striae. ......................................................................................... O. integer SHARP, 1876

24. Clypeus with thick obtuse lateral prominence and a long acute tooth, separated by a broad and deep emargination (Fig. 25d). ................................................ O. tschirnhausi sp. n.

- Clypeus only with lateral obtuse prominences. ........................................................... 25

25. Pronotum with weak microsculpture, surface shiny, but not polished. ....................... 26

- Pronotum with dense and distinct microsculpture, surface matte or only slightly shiny. .. ................................................................................................................................... 27

26. Clypeus with numerous granulate punctures ( Fig. 39 C ), except on a small space in the middle. ........................................................................ O. granulatus BERNHAUER ,, 1920

- Clypeus without granulate punctures. .............................................. O. guianensis sp. n.

27. Larger, 10 – 11 mm long. .......................................................................................... 31

- Smaller than 8.5 – 9.6 mm. ....................................................................................... 28

28. Pronotum very finely and sparsely punctate, microsculpture deep and dense, surface matte ( Fig. 38 G ). ................................................................................ O. dubius SHARP, 1887

- Punctation of pronotum deeper and denser, microsculpture weaker, surface slightly shiny (38 H). ...................................................................................................................... 29

29. Pronotum more or less triangular (Fig. 28a), with dense punctation, elytra with deep coriaceous ground sculpture, apex of aedeagus thick and obtuse (Fig. 28c). ..................... ................................................................................................ O. morio NOTMAN, 1925

- Pronotum with slight and short emargination in front of posterior angles, punctation sparser, apex of aedeagus acute. .................................................................................. 30

30. Elytra dark brown with weak ground sculpture, punctures distinct, punctation of pronotum sparser, distance between punctures on average wider than diameter of punctures, surface matter, apex of aedeagus short and acute (Fig. 29c). .............. O. piceus ERICHSON, 1840

- Elytra black with deeper ground sculpture, punctures indistinct, punctation of pronotum denser ( Fig. 37 C ), distance between punctures on average as wide as diameter of punctures, apex of aedeagus long and acute ( Fig. 30c ). .................................. O. continentaluscontinentalus sp. n.

31. Microsculpture of pronotum dense and deep, surface matte, punctation irregular and sparser, distance between punctures wider than diameter of punctures, aedeagus with obtuse apex (Fig. 31c). ...................................................................... O. sahlbergi BERNHAUER ,, 1920

- Microsculpture of pronotum weaker, surface slightly shiny, punctation denser, distance between punctures shorter than diameter of punctures, aedeagus with acute apex. ..... 32

32. Pronotum strongly narrowed from anterior to posterior angles, anterior edge more than 1.3 times wider than posterior edge. ........................................................................... 33

- Pronotum less narrowed from anterior to posterior angles, anterior edge less than 1.3 times wider than posterior edge. .......................................................................................... 34

33. Punctation of pronotum coarse and dense, distance between punctures on average only half as wide as diameter of punctures ( Fig. 38 H ), with deep longitudinal depression (Fig. 32a). ............................................................................................ O. confusus NOTMAN, 1925

- Punctation of pronotum slightly weaker, but as dense, on average only half as wide as diameter of punctures, without longitudinal depression ( Fig. 33a ). ................................. .............................................................................................. O. puncticeps SHARP, 1887

34. Punctation of pronotum sparser and finer, distance between punctures wider than diameter of punctures, microsculpture weaker. .......................... O. propinquus BERNHAUER ,, 1920

- Punctation of pronotum denser and coarser, distance between punctures shorter than diameter of punctures, microsculpture deeper, surface matter. ..... O. nitens SHARP, 1876

Figures

Fig. 1: Osorius ater. - Fig. 2: O. stipes. - Fig. 3: O. alternansalternans (a: front body, b: antenna, c: aedeagus in ventral and lateral aspect, d: clypeus with labrum, e: head in lateral aspect; scale bar a, b: 1 mm, c, d, e: 0.5 mm).

Fig. 4: Osorius brasiliensis. - Fig. 5: O. intermedius. - Fig. 6: O. columbinus (a: front body, b: antenna, c: aedeagus in ventral and lateral aspect, d: prosternal process, e: head in lateral aspect; scale bar a, b, e: 1 mm, c, d: 0.5 mm)

Fig. 39: Pronotum of Antillosorius daemon ((A), pronotum of Osoriellus eggersieggersi (B), and fore head of Osorius granulatusgranulatus (C) (scale bar 1 mm).

Fig. 38: Surface of elytra of Osorius columbinus (A), O. brasiliensis (B), and surface of pronotum of O. dentatus (C), O. paganus (D), O. pusillus (E), O. peruvianus (F), O. dubius (G), O. confusus (H) (scale bar: 0.5 mm).

Fig. 36: Head and pronotum of Osorius verhaaghi ((A), O. paganus (B), O. venezuelanus (C), O. pusillus (D) (scale bar: 1 mm).

Fig. 20: O. ashei. - Fig. 21: O. laevigatulus. - Fig. 22: O. wasmanni. - Fig. 23: Osorius peruvianusperuvianus (a: front body, b: antenna, c: aedeagus in ventral and lateral aspect, d: clypeus; scale bar: a, b, d: 1 mm, c: 0.5 mm).

Fig. 37: Head and pronotum of O. asheiashei ((A), O. tschirnhausitschirnhausi (B), O. continentalus (C), O. guianensisguianensis (D) (scale bar: 1 mm).

Fig. 30: Osorius continentalus. - Fig. 31: O. sahlbergi. - Fig. 32: O. confusus (a: front body, b: antenna, c: aedeagus in ventral and lateral aspect; scale bar: a, b: 1 mm, c: 0.5 mm).

Fig. 33: Osorius puncticeps. - Fig. 34: O. propinquus. - Fig. 35: O. nitens (a: front body, b: antenna, c: aedeagus in ventral and lateral aspect; scale bar: a, b: 1 mm, c: 0.5 mm).