Torobus purpurascens ( Nordmann, 1837 )

Chatzimanolis, Stylianos, 2018, A Review of the Genera Dysanellus Bernhauer and Torobus Herman (Coleoptera: Staphylinidae: Staphylininae: Staphylinini), The Coleopterists Bulletin 72 (2), pp. 279-291 : 288-289

Torobus purpurascens ( Nordmann, 1837)

( Figs. 4 , 8 , 15 , 22–24 , 26 )

Staphylinus purpurascens Nordmann 1837: 47 .

Trigonopselaphus purpurascens (Nordmann) ; Gemminger and Harold 1868: 597.

Trigonurus [sic; lapsus of Trigonopselaphus] brasilianus Bernhauer 1906: 327 . New synonymy.

Trigonopselaphus brasilianus (Bernhauer) ; Bernhauer and Schubert 1914: 403.

Torobus purpurascens (Nordmann) ; Herman 2001a: 29.

Torobus brasilianus (Bernhauer) ; Herman 2001a: 29.

Type Material. Lectotype of Staphylinus purpurascens , here designated, with labels: “Type” / “5976” / “Hist. -Coll. ( Coleoptera ) Nr. 5976 Staphylinus purpurascens Nordm. Brasil v. Langsdorff Zool. Mus. Berlin” / “ SYNTYPE Staphylinus purpurascens Nordmann, 1837 labelled by MFNB 2017” / “ Lectotype Staphylinus purpurascens Nordmann des. Chatzimanolis 2017 ” / “ Torobus purpurascens Nordmann det. Chatzimanolis 2017 ”. In the collection of ZMHB . Paralectotypes, two females, here designated, with labels “Type” / “Hist. -Coll. ( Coleoptera ) Nr. 5976 Staphylinus purpurascens Nordm. Brasil v. Langsdorff Zool. Mus. Berlin” / “ SYNTYPE Staphylinus purpurascens Nordmann, 1837 labelled by MFNB 2017” / “ Paralectotype Staphylinus purpurascens Nordmann des. Chatzimanolis 2017 ” / “ Torobus purpurascens Nordmann det. Chatzimanolis 2017 ”. In the collection of ZMHB .

Holotype for Torobus brasilianus , male with labels: “ Brasilien Bang-Haas” / “ Trigonurus brasilianus Brh Typus det. Bernhauer” / “ brasilianus Bernh Typ. ” / “Chicago NHMus. M. Bernhauer Collection” / “ HOLOTYPE teste A. Westrich 2015 GDI Imaging Project” / “PHOTOGRAPHED Kelsey Keaton 2015 Emu Catalog” / “FMNHNS3047815 Field Museum Pinned”. In the collection of FMNH. Photographs of the holotype and labels for T. brasilianus are available at collections-zoology.fieldmuseum.org/catalogue/3047815.

Additional Material. BRAZIL: Bahia: unknown locality (1 male, BMNH) ; Esp´ırito Santo: Fazenda Jerusalem , 3.xii.1913, J. F. Zikan (1 female, FMNH) ; Trijuco Preto , 900 m, iii.1940, E. Reitter (1 male, NMW) ; unknown locality, Descourtilz (1 male, 1 female, FMNH) ; unknown locality (1 female, BMNH) ; Minas Gerais: Santa Bárbara , iii.1957 (1 female, NMW) ; unknown locality (1 male, BMNH) ; Rio de Janeiro: Nova Friburgo (1 male, MHNG) ; Rio Grande do Sul: Rio Grande (1 female, BMNH) ; Santa Catarina: Hansa Humboldt , viii.1939, E. Reitter (2 males, NMW) ; S ‾ ao Paulo: Cantareira, A. Bierig (1 male, FMNH) ; same locality, 8.xii.1929, J. Halik, UTCI000004381 (1 male, UTCI) ; Mogi des Cruzes, 50 km SE Sierra do Mar., Est. Biol. Boraceia , 800–900 m, 28–30.iv.1997, F. Genier, SM0156870, SM0156872, SM0156874 (3 males, SEMC) ; Unknown state: (1 male, 2 females, BMNH; 2 females, FMNH) ; Bescke , GAC7936 (1 female, MZH) ; PARAGUAY: Alto Paraná: Hohenau , 26. viii.1934, J. Jacob (1 female NMW) ; UNKNOWN COUNTRY: (1 male, NMW) ; Kraatz (2 males, SDEI; 1 female, MHNG) ;

Diagnosis. Torobus purpurascens can be easily distinguished from T. laetipes due to the overall different color patterns in these two species. Besides the different coloration, T. purpurascens can be distinguished from T. laetipes based on the shape of the head (head rectangular in T. purpurascens , rounded in T. laetipes ) and the shape of the aedeagus (paramere much wider in T. laetipes than in T. purpurascens ).

Description. Body length 14.9–20.1 mm. Coloration of head and pronotum dark metallic purple to metallic green-red; elytra dark metallic bluepurple; mouthparts, antennae, mesoscutellum, legs, ventral surface of body, and abdomen brown except VIII variable from brown to orange. Head transverse, with posterolateral corners slightly expanded, width:length ratio = 1.29, rectangular. Epicranium with transverse microsculpture and micropunctures; with few medium-sized punctures around margin of head and eyes and few other scattered medium-sized punctures on epicranium. Clypeus slightly emarginate. Eyes medium-sized, length of eyes / length of head ratio = 0.48, distance between eyes as wide as 1.80 times length of eye. Neck with transverse microsculpture and few micropunctures. Pronotum longer than wide, width: length ratio = 0.91; surface of pronotum uniformly covered with sparse transverse microsculpture and micropunctures; appearing shiny. Pronotum without well-defined rows of punctures at disc; at most with 2–3 punctures near center; few scattered mediumsized punctures near anterolateral margins; pronotal margin with thick area of micropunctures, appearing as a fine grey line around margin. Elytra not appearing smooth; with medium-sized to large, deep punctures (about 11–12 punctures / elytral width); distance between punctures equal to width of puncture; elytra with rugose microsculpture. Abdominal tergum III with faint subbasal (archlike) carina; tergum IV with slightly less delineated subbasal (arch-like) carina. Male secondary sexual structures ( Fig. 15 ) on sternum VII with slight emargination medially; porose structure present on sternum VII [see Remarks below]; sternum VIII with shallow, U-shaped emargination medially; sternum IX with deep, V-shaped emargination medially. Female without obvious sexual structures. Aedeagus as in Figs. 22–24 ; in dorsal view, paramere narrow [in comparison to T. laetipes ], converging to rounded tip; paramere slightly longer (or subequal) and narrower than median lobe; in lateral view, paramere concave, narrower apically; paramere with peg setae along the anterior lateral margins. Median lobe in dorsal view wide, converging to narrowly rounded apex, with a large tooth apically; in lateral view, becoming much narrower near apex.

Distribution. Known from several states in Brazil and the department of Alto Parańa in Paraguay.

Remarks. Bernhauer (1906) mentioned that T. brasilianus was different from T. purpurascens due to the coloration and the smaller head and pronotum. However, after comparing all taxa that were previously identified by Bernhauer, Scheerpeltz, and others as belonging to these two species, as well as the type material, I cannot find any significant differences in the shape of the aedeagi. Additionally, the minor differences in coloration and size among specimens do not form any clear geographic patterns.

Chatzimanolis (2013) erroneously mentioned that T. purpurascens has no porose structure while comparing that species with members of Terataki . The porose structure on T. purpurascens is positioned rather anteriorly on the segment, and it was obscured by the preceding segments on the rather limited number of specimens I examined at that time.

Figures

Figs. 3–4. Torobus species, habitus. 3) T. laetipes, total length = 17.2 mm; 4) T. purpurascens, total length = 18.3 mm.

Figs. 7–8. Heads and pronota of Torobus species. 7) T. laetipes; 8) T. purpurascens. Not to scale.

Figs. 13–15. Abdominal sterna VII and VIII. Arrows indicate the position of porose structure. 13) Dysanellus transverserugosus (While there is a broad area with no setae on VII, it is not clear if there is a porose structure. See text for more details); 14) Torobus laetipes; 15) Torobus purpurascens. Not to scale.

Figs. 22–24. Aedeagus of Torobus purpurascens. 22) Dorsal view; 23) Lateral view; 24) Paramere, ventral view.

Fig. 26. Distribution map of Torobus laetipes and Torobus purpurascens.