Osoriinae, Erichson, 1839

Irmler, Ulrich, 2015, Osoriinae of Cuba with description of new species and an identification key (Coleoptera: Staphylinidae), Acta Entomologica Musei Nationalis Pragae 55 (1), pp. 145-172 : 158-168

Key to genera and species of the Cuban Osoriinae

1 Inner edge of protibia emarginate. Tribe Osoriini . ….................................................. 22

– Inner edge of protibia even, without emargination. Tribe Thoracophorini . ................... 2

2 Elytra with three to four longitudinal carinae or remnants of carinae. Genus Thoracophorus Motschulsky, 1837 . .................................................................................................. 3

– Elytra without longitudinal carinae. ............................................................................... 5

3 Eyes totally visible in dorsal aspect, elytra with remnants of carinae, lateral margin of pronotum even ( Fig. 5D ), aedeagus ( Fig. 3A ). ......... Thoracophorus cubensis sp. nov.

– Eyes at least partly covered by supraocular carinae, lateral margin of pronotum denticulate. ................................................................................................................................. 4

4 Eyes totally covered by supraocular carinae ( Fig. 5B ), aedeagus ( IRMLER 1985: Fig. 7c ). ....................................................................... Thoracophorus brevicristatus Horn, 1871

– Eyes only partly covered by supraocular carinae ( Fig. 5C ), aedeagus ( IRMLER 1985: Fig. 23c). ...................................................... Thoracophorus guadalupensis Cameron, 1913

5 Minute species of 1.4 to 1.6 mm, sides of pronotum deeply emarginate in front of posterior angles, ( Fig. 5E ), aedeagus ( IRMLER 2012: Figs 9c,d ). ............................................... .................................................................................... Espeson moratus Schaufuss, 1882

– Longer than 2.0 mm, sides of pronotum with less deep emargination in front of posterior angles. ............................................................................................................................. 6

6 Abdominal sternites with diagonal striae. Genus Lispinus Erichson, 1840 . .................. 7

– Abdominal sternites without diagonal striae ................................................................ 10

7 Sides of pronotum divergent to posterior angles, second antennomere elongate, nearly three times longer than the third ( Fig. 7F ), aedeagus ( IRMLER 1994: Fig. 7c ). .................. .................................................................................... Lispinus laticollis Erichson, 1840

– Sides of pronotum nearly parallel or convergent to posterior angles, second antennomere not three times longer than the third. .............................................................................. 8

8 Elytra and antennomeres 4 and 5 longer than wide ( Fig. 7E ), aedeagus ( IRMLER 1994: Fig. 1c ). ................................................................................. Lispinus cubensis Irmler, 1994

– Elytra and antennomeres 4 and 5 quadrate or wider than long. ..................................... 9

9 Sides of pronotum nearly parallel, elytra with longitudinal furrow, 4.8–5.0 mm long ( Fig. 8A ), aedeagus ( IRMLER 2012 a: Fig. 3k ). ........................ Lispinus striola Erichson, 1840

– Sides of pronotum distinctly narrowed to posterior angles, elytra without longitudinal furrows, smaller than 4.0 mm ( Fig. 8B ), aedeagus ( IRMLER 2000: Figs 5e,f ). .................. .................................................................. Lispinus insularis Chevrolat & Fauvel, 1863

10 Elytra distinctly wider than long ( Fig. 5A ), aedeagus ( Fig. 1A ). ...................................... .......................................................................................... Allotrochus cubensis sp. nov.

– Elytra only slightly wider than long, quadrate or longer than wide. ............................ 11

11 Male antennae considerably longer than head, eyes distinctly prominent, semicircular ( Fig. 6F ). ............................................................................... Tannea picata Irmler, 2003

– Length of male and female antennae equal, eyes not semicircular. ............................. 12

12 Antennae only slightly longer than head, gular sutures combined throughout their total length; parthenogenetic species. Genus Clavilispinus Bernhauer, 1926 . ..................... 13

– Antennae only slightly shorter than head and pronotum combined, gular sutures at least partly divided. Genus Nacaeus Blackwelder, 1942 . ................................................... 16

13 Surface of pronotum and elytra without microsculpture, polished and shiny ( Fig. 7C ). .. .................................................................................... Clavispinus politus ( Sharp, 1887)

– Surface of pronotum and elytra with dense microsculpture, matt.................................14

14 Colouration yellow, smaller than 2.8 mm. ................................................................... 15

– Colouration dark and between 2.8 and 3.0 mm long ( Fig. 7B ). ........................................ ...................................................................... Clavispinus megacephalus ( Fauvel, 1865)

15 Smaller species of 1.9 to 2.1 mm length ( Fig. 7A ). .......................................................... ............................................................................... Clavispinus exiguus ( Erichson, 1840)

– Larger species of 2.4 to 2.5 mm length ( Fig. 7D ). .. Clavispinus minutus ( Sharp, 1887)

16 Extremely depressed, yellow, eyes small, much shorter than temples ( Fig. 5F ), aedeagus ( IRMLER 2003a: Fig. 26e). ........................................... Nacaeus planellus ( Sharp, 1887)

– Only slightly depressed; dark brown or only pronotum and elytra yellow; eyes larger and longer than temples. ..................................................................................................... 17

17 Elytra and/or pronotum yellow, smaller species of approximately 2 mm length. ........ 18

– Brown or black; at least 2.5 mm long. ......................................................................... 20

18 Pronotum and elytra light brown to yellow, head dark or light brown. ....................... 19

– Only elytra light yellow, head and pronotum brown ( Fig. 6E ), aedeagus ( IRMLER 2003a: Figs 44e,f). .............................................................. Nacaeus flavipennis ( Fauvel, 1865)

19 Microsculpture of elytra isodiametric, head dark brown ( Fig. 6D ), aedeagus ( IRMLER 2003a: Figs 40e,g). ............................. Nacaeus nigrifrons ( Chevrolat & Fauvel, 1863)

– Microsculpture of elytra longitudinal, head light brown ( Fig. 6C ), aedeagus ( IRMLER 2003: Figs 42e,g). .............................................................. Nacaeus laetus (Sharp, 1876)

20 Punctures on elytra sparse and fine; hardly visible in isodiametric microsculpture, smaller, between 2.5 mm and 3 mm long, punctation of pronotum fine and sparse, elytra longer than wide ( Fig. 6A ), aedeagus ( Fig. 2A ). .......... Nacaeus dejectus ( Sharp, 1887)

– Punctures on elytra distinctly visible, microsculpture irregular, netlike and partly longitudinal, elytra approximately quadrate ( Fig. 6B ), aedeagus ( IRMLER 2003a: Fig. 30e) ..... ............................................................................. N. impressicollis ( Motschulsky, 1857)

21 Outer edge of protibia with spines, antennae geniculate. ............................................ 23

– Outer edge of protibia with setae, antennae not geniculate. ......................................... 22

22 Sides of pronotum evenly curved; widest in the middle and without emargination in front of posterior angles ( Fig. 8D ), aedeagus ( IRMLER 1981a: plate 7 Fig. 1b ). ......................... ................................................................ Holotrochus minor Chevrolat & Fauvel, 1863

– Sides of pronotum deeply emarginate in front of posterior angles ( Fig. 8C ), aedeagus ( IRMLER 1981b: Fig. 1d ). ........................................... Mimogonus fumator Fauvel, 1889

23 Body with only few setae, sides of pronotum at least slightly emarginate in front of posterior angles, lateral margin of pronotum widened from anterior to posterior angles; third antennomere nearly twice as long as second. Genus Antillosorius Irmler, 2010 . ........ 29

– Body with setiferous punctation, sides of pronotum not sinuate in front of posterior angles. Genus Osoriellus Fagel, 1958 . ............................................................................ 24

24 Smaller than 2.9 mm, head brown, pronotum, elytra and abdomen light yellow ( Fig. 8F ), aedeagus ( IRMLER 2014: Fig. 43C) ......................... Osoriellus exiguus ( Notman, 1925)

– Larger, at least 3.0 mm. ................................................................................................ 25

25 Pronotum with isodiametric microsculpture, surface matt ( Fig. 9A ), aedeagus ( IRMLER 2014: Fig. 48C). .................................................. Osoriellus lewisi ( Blackwelder, 1943)

– Pronotum without or with weak microsculpture, surface shiny. .................................. 26

26 Pronotum with large punctures placed in irregular longitudinal rows and with wide impunctate midline. .......................................................................................................... 27

– Pronotum with fine and dense punctation and narrow impunctate midline ( Fig. 8E ), aedeagus ( IRMLER 2014: Fig. 62C). .......................... Osoriellus eggersi (Bernhauer, 1904)

27 Small species of 3.5 to 3.9 mm length ( Fig. 9B ), aedeagus ( IRMLER 2014: Fig. 65C). ..... ................................................................................. Osoriellus obtusicollis Irmler, 2014

– Species longer than 4.0 mm. ........................................................................................ 28

28 Smaller species of 4.7 mm length ( Fig. 9D ), pronotal punctation sparser, on average, interstices between punctures twice as wide as diameter of punctures, aedeagus ( IRMLER 2014: Fig. 86C). ............................................... Osoriellus haitiellus ( Darlington, 1937)

– Larger species of 5.1–5.5 mm length ( Fig. 9C ), pronotal punctation denser, on average, interstices between punctures as wide as diameter of punctures, aedeagus ( IRMLER 2014: Fig. 81C). ............................................................... Osoriellus schwarzi ( Notman, 1925)

29 Abdominal tergites only with single setiferous punctures. .......................................... 30

– Abdomen with moderately dense setiferous punctation. ............................................. 31

30 Anterior edge of clypeus deeply denticulate ( Fig. 9E ). ....................................................... ..................................................................... Antillosorius crenulifrons ( Notman, 1925)

– Anterior edge of clypeus not deeply denticulate, only undulate ( Fig. 9F ). ....................... ................................................................ Antillosorius darlingtoni ( Blackwelder, 1943)

31 Eyes extremely large and prominent ( Fig. 10A ). ............ Antillosorius martini sp. nov.

– Eyes not or slightly prominent. ................................................................................... 32

32 Pronotum strongly narrowed to posterior angles and deeply emarginate in front of posterior angles. .................................................................................................................... 33

– Pronotum slightly narrowed to posterior angles and not deeply emarginate in front of them. ............................................................................................................................. 34

33 Clypeus nearly semicircular, anterior face of protibia with row of setiferous punctures ( Fig. 10B ). ............................................... Antillosorius turquinus ( Blackwelder, 1943)

– Anterior edge of clypeus straight, anterior face of protibia with scattered setiferous punctures ( Fig. 10C ). ........................................... Antillosorius strictus ( Blackwelder, 1943)

34 Small species of 5 mm length, elytra as long as pronotum ( Fig. 10D ). ............................ ............................................................................... Antillosorius buscki ( Notman, 1925)

– Larger species of at least 7 mm, elytra longer than pronotum. .................................... 35

35 Pronotum slightly emarginate in front of posterior angles. .......................................... 36

– Pronotum smoothly rounded to posterior angles. ......................................................... 37

36 Pronotum with extremely weak microsculpture; surface nearly polished, shiny, front edge of clypeus smaller, 0.45 times as wide as space between eyes ( Fig. 10F ). ............... ........................................................................... Antillosorius socors ( Darlington, 1937)

– Pronotum with deep microsculpture, surface matt, front edge of clypeus wider, 0.6 times as wide as space between eyes ( Fig. 10E ). ........... Antillosorius manni ( Notman, 1925)

37 Anterior face of protibia with row of setiferous punctures, microsculpture of pronotum extremely fine, nearly polished, surface shiny ( Fig. 11B ). ................................................ ....................................................................... Antillosorius oriente ( Blackwelder, 1943)

– Anterior face of protibia with scattered setiferous punctures, pronotal microsculpture less deeper, surface rather shiny ( Fig. 11A ). ...... Antillosorius cubensis ( Blackwelder, 1943)

Figures

Fig. 5. Head, pronotum and elytra, showing shape, punctation and microsculpture. A – Allotrochus cubensis sp. nov.; B – Thoracophorus brevicristatus Horn, 1871; C – T. guadalupensis Cameron, 1913; D – T. cubensis sp. nov.; E – Espeson moratus Schaufuss, 1882; F – Nacaeus planellus (Sharp, 1887). Scale bars: 0.2 mm (A–E), 0.5 mm (F).

Figs 1–4: Morphological details of Cuban Osoriinae. 1 – Allotrochus cubensis sp. nov.; 2 – Nacaeus dejectus (Sharp, 1887); 3 – Thoracophorus cubensis sp. nov.; 4 – Antillosorius martini sp. nov. Body parts: A – aedeagus in lateral/ ventral aspect; B – paramere; C – last abdominal tergite; D – last abdominal sternite; E – antenna; F – protibia in posterior aspect. Scale bars: 0.1 mm.

Fig. 7. Head, pronotum and elytra, showing shape, punctation and microsculpture. A – Clavilispinus exiguus (Erichson, 1840); B – C. megacephalus (Fauvel, 1865); C – C. politus (Sharp, 1887); D – C. minutus (Sharp, 1887); E – Lispinus cubensis Irmler, 1994; F – L. laticollis Erichson, 1840. Scale bars: 0.2 mm (A–D), 0.5 mm (E–F).

Fig. 9. Head, pronotum and elytra, showing shape, punctation and microsculpture. A – Osoriellus lewisi (Blackwelder, 1943); B – O. obtusicollis Irmler, 2014; C – O. schwarzi (Notman, 1925); D – O. haitiellus (Darlington, 1937); E – Antillosorius crenulifrons (Notman, 1925); F – A. darlingtoni (Blackwelder, 1943). Scale bars: 0.5 mm.

Fig. 8.Head, pronotum and elytra, showing shape, punctation and microsculpture.A – Lispinus striola Erichson,1840; B – L. insularis Chevrolat & Fauvel, 1863; C – Mimogonus fumator Fauvel, 1889; D – Holotrochus minor Chevrolat & Fauvel, 1863; E – Osoriellus eggersi (Bernhauer, 1904); F – O. exiguus (Notman, 1925). Scale bars: 0.5 mm.

Fig. 6. Head, pronotum and elytra, showing shape, punctation and microsculpture. A – Nacaeus dejectus (Sharp, 1887); B – N. impressicollis (Motschulsky, 1857); C – N. laetus (Sharp, 1876); D – N. nigrifrons Chevrolat & Fauvel, 1863; E – N. flavipennis (Fauvel, 1865); F – Tannea picata Irmler, 2003. Scale bars: 0.2 mm (A–E), 0.5 mm (F).

Fig. 10. Head, pronotum and elytra, showing shape, punctation and microsculpture. A – Antillosorius martini sp. nov.; B – A. turquinus (Blackwelder, 1943); C – A. strictus (Blackwelder, 1943); D – A. buscki (Notman, 1925); E – A. manni (Notman, 1925); F – A. socors (Darlington, 1937). Scale bars: 0.5 mm.

Fig.11.Head, pronotum and elytra,showing shape, punctation and microsculpture. A – Antillosorius cubensis (Blackwelder, 1943); B – A. oriente (Blackwelder, 1943). Scale bars: 0.5 mm.