Ocyolinus Sharp, 1884

Chatzimanolis, Stylianos & Ashe, James S., 2009, A revision of the neotropical genus Ocyolinus (Coleoptera: Staphylinidae: Staphylinini), Zootaxa 2162, pp. 1-23 : 3-6

Ocyolinus Sharp, 1884

( Figs. 1–49 )

Ocyolinus Sharp, 1884: 363 .

Type species. Ocyolinus rugatus Sharp, 1884 , fixed by virtual monotypy and direct implication ( Herman, 2001: 3582).

Diagnosis. Ocyolinus can be distinguished from other genera in the subtribe Xanthopygina by the combination of the following characters: a) mandibles extremely elongate, each with a single triangular tooth that is typically slightly different in right and left mandible; b) maxillary and labial palpi expanded, but never as dilated as in Dysanellus Bernhauer, 1911 ; c) antennomere 11 with a distal white patch of setae; d) head subquadrate, never trapezoid (as in Dysanellus or Torobus Herman, 2001 ); e) integument of head and pronotum with microsculpture; f) terga V–VI without subbasal carinae; g) median lobe of aedeagus with a pair of dorsal teeth. Due to body coloration, Ocyolinus looks superficially similar to several species of Gastrisus Sharp, 1876 , Nausicotus Sharp, 1884 and Torobus , but can be easily distinguished from them because the latter species do not have elongate mandibles. Dysanellus bruchi Bernhauer, 1911 and D. transverserugosus Bernhauer, 1921 have mandibles similar in shape to the ones found in Ocyolinus , but they have extremely securiform labial palpi and trapezoid-shaped head. Torobus principalis ( Bernhauer, 1911) has similar coloration and the mandibles are as elongate as in Ocyolinus , but the structure of the mandibular tooth is different (appearing having a small dorsal and a large ventral tooth) as well as the overall shape of head and the pronotum punctation pattern.

The phylogenetic relationships within Ocyolinus as well as its relationship with other genera such as Dysanellus and Torobus will be discussed in more details in a forthcoming paper (Chatzimanolis, in preparation).

Description. Habitus as in Figs. 1–3 , body medium sized, 10.5–17.0 mm in total length.

Coloration. Color of head and pronotum similar, in most species metallic dark purple with green and blue overtones, in other species with shining metallic brown with green overtones; most species with elytra metallic dark purple with green and blue overtones or dark metallic brown with green and blue overtones. Mouthparts reddish brown to orange. Abdomen dark brown, except in some posterior segment of sternum VII and VIII orange. Surface of abdomen appearing matt in some due to polygon-shaped microsculpture.

Head ( Figs. 4–9 ) subquadrate to slightly transverse; posterior angles rounded; eyes of medium size, prominent, occupying almost half of lateral margins of head; nuchal depression very prominent dorsally, forming well-defined neck 1/3 to 1/2 width of head; punctures on dorsal surface of neck various. Umbilicate punctation on epicranium various among species, from sparsely distributed along lateral and posterior margins to very densely distributed and confluent punctures. Epicranium flat, with polygon-shaped or transverse microsculpture visible at magnifications> 70X, with large prominent macrosetae along border of head. Anteclypeus well developed, moderately sclerotized. Ventrally, head with incomplete (obsolete medially) postmandibular ridge and well developed infraorbital ridge (except in O. rugatus faint). Gular sutures separated in anterior third, converging to narrow separation in posterior 2/3.

Antenna ( Fig. 17 ) with antennomeres 1–11 elongate; antennomeres 1–3 with multiple rows of macrotrichae; antennomeres 4–11 with three rows of macrotrichiae, covered with microtrichiae; anntenomere 11 with round white patch lacking microsetae apically.

Labrum ( Fig. 21 ) medially emarginate to near its base. Mandibles as in Figs. 4–9 , 16 ; extremely elongate, curved or straight distally; mandibles with shallow fold on lateral edge (dorsal view) extending from condylar region to anterior margin of tooth, fold with pores; right and left mandibles nearly symmetrical except shape of medial tooth; left mandible with strongly convex elongate to broadly triangular tooth; right mandible with strongly convex elongate to flat broadly triangular tooth with or without constriction apically; prostheca sparingly setose. Maxilla as in Fig. 19 ; galea and lacinia densely setose. Maxillary palpi 4-segmented; P1 (= first palpomere) short, less than 1/3 length of P2; P2–P4 elongate, P2 about 1.5 times as long as P3; P3 subequal in length to P4; P2–P3 club-like. Hypopharynx and labium as in Fig. 20 . Anterior margin of mentum with broad emargination medially, mentum with two anterolateral setae in each end. Ligula short, membranous, entire. Labial palpi 3-segmented, P1 slightly smaller than P2; P3 longer than P2. P2 with medial, lateral constriction; P3 slightly securiform.

Pronotum (Figs. 10–15) subquadrate to elongate; hypomeron expanded; superior and inferior marginal lines of hypomeron separate throughout their lengths; superior line fully visible from above, prominent, extended around antero-lateral margin of pronotum and contacting inferior line at neck fossa, no portion of dorsum of pronotum visible from below. Umbilicate punctation on pronotum varies among species; sparse to densely punctuated, size of punctures varies; antero-lateral parts of pronotum densely punctuated. Pronotum appearing matt in most species due to the presence of micropunctures and microsculpture (shining in O. ganglbaueri and O. rugatus ). Pronotum with row of confluent or almost confluent punctures along the lateral margins of pronotum. Microsetae directed more or less postero-medially or posteriorly. Basisternum of prosternum with pair of prominent medial setae and microsculpture; anterior marginal depression present; without medial carina. Sternacostal ridge present; intercoxal depression anterior to subcoxal ridge present. Furcasternum with prominent medial carina.

Elytra subequal in length to pronotum, moderately densely and uniformly punctuate and microsetose; with large prominent macrosetae along lateral margins of elytra. Elytra depressed near mesoscutellum. Hind wings fully developed.

Mesoventrite with anterior margin reflexed into slight “lip”; with medial carina; mesoventral process triangular and pointed apically, extended about 2/5 distance between mesocoxae; metaventral processes small, triangular and rounded apically, extended about 1/5 distance between metacoxae, appearing light brown.

Tarsal segmentation 5-5-5. Protarsal articles 1–4 of both sexes slightly to moderately transverse, covered ventrally by spatulate setae. Tarsal articles of middle and hind legs symmetrical, not enlarged or dilated. Empodium with 2 small setae. Protibia with row of spurs at distal margin, without any other spurs (except in O. amethystinus and O. nebulosus ), ctenidium present. Meso- and metatibia with multiple rows of spurs.

Abdomen with paired prototergal glands present in first abdominal tergum. Abdominal terga III–VII with tergal basal carina, terga III–IV with subbasal (arch-like) tergal carina in some, absent in others, terga V–VII without subbasal carina. Abdominal sterna with transverse basal ridges well developed on sterna III–VII. Sterna VII–VIII with shallow depressions 2/5 from posterior margin.

Male and female genitalia typical of Staphylinini . Male ( Fig. 23 ) and female tergite IX composed of two elongate, narrow lateral sclerites. In females, basal valvifers with microsculpture; second gonocoxites without microsculpture; apical stylus small. Spermatheca not sclerotized. Aedeagus typical of Staphylinini , with large median lobe and single paramere. Paramere in all species with sensory spinules (peg setae) and short apical setae. Median lobe with pair of dorsal teeth in all species and with hook-like apical tooth in O. rugatus and O. ganglbaueri .

Females without obvious secondary sexual characters. Males with distal margin of sternum VII with slight broad emargination medially ( Fig. 23 ); sternum VIII with shallow V-shaped emargination medially ( Fig. 23 ); sternum IX with deep V-shaped emargination medially ( Fig. 23 ).

Figures

FIGURES 1 – 3. Habitus photographs of Ocyolinus. 1. O. amethystinus, holotype. 2. O. rugatus, lectotype. 3. O. nebulosus, paratype.

FIGURES 4 – 9. Head of Ocyolinus. 4. O. amethystinus. 5. O. astenos. 6. O. dimoui. 7. O. ganglbaueri. 8. O. nebulosus. 9. O. rugatus.

FIGURES 16 – 22. Ocyolinus ganglbaueri. 16. Ventral view of left mandible, showing the prostheca, scale bar = 1 mm. 17. Antenna, scale bar = 1.6 mm. 18. Protibia, scale bar = 1 mm. 19. Right maxilla, scale bar = 0.7 mm. 20. Hypopharynx and labial palpi, scale bar = 0.8 mm. 21. Labrum, scale bar = 0.6 mm. 22. Ventral view of paramere showing the sensory spinules (peg setae), scale bar = 0.2 mm.

FIGURES 23 – 24. Ocyolinus ganglbaueri. 23. Ventral view of male abdominal sterna. 24. Magnification of anterior part of sternum VIII showing the polygon-shaped microsculpture.

FIGURES 25 – 28. Aedeagus of O. amethystinus. 25. Dorsal view. 26. Lateral view. 27. Detail of median lobe, lateral view. 28. Detail of paramere, ventral view.

FIGURES 29 – 32. Aedeagus of O. astenos. 29. Dorsal view. 30. Lateral view. 31. Detail of median lobe, lateral view. 32. Detail of paramere, ventral view.

FIGURES 33 – 36. Aedeagus of O. dimoui. 33. Dorsal view. 34. Lateral view. 35. Detail of median lobe, lateral view. 36. Detail of paramere, ventral view.

FIGURES 37 – 40. Aedeagus of O. ganglbaueri. 37. Dorsal view. 38. Lateral view. 39. Detail of median lobe, lateral view. 40. Detail of paramere, ventral view.

FIGURES 41 – 44. Aedeagus of O. nebulosus. 41. Dorsal view. 42. Lateral view. 43. Detail of median lobe, lateral view. 44. Detail of paramere, ventral view.

FIGURES 45 – 48. Aedeagus of O. rugatus. 45. Dorsal view. 46. Lateral view. 47. Detail of median lobe, lateral view. 48. Detail of paramere, ventral view.

FIGURE 49. Distribution map of Ocyolinus.