Dysanellus transverserugosus Bernhauer, 1921

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 : 283-285

Dysanellus transverserugosus Bernhauer, 1921

( Figs. 2 , 6 , 9 , 12–13 , 16–18 , 25 )

Dysanellus transverserugosus Bernhauer 1921: 175 .

Type Material. Holotype, female, with labels: “[ Brazil] Ypiranga, Lüderw. leg, xi.[19]12” / “ Dysanellus transverserugosus Typus” / “Chicago NHMus. M. Bernhauer Collection ”. In the collection of FMNH.

Additional Material. BRAZIL: Minas Gerais: Fonseca, 1919 (1 male FMNH) ; Rio de Janeiro: Petropolis. H. Schultz (1 female, FMNH) ; S~ ao Paulo: Campos de Jord ~ ao, K. Lenko, vii.1957 (1 female, AMNH) ; Ipiranga , iv.1919 (1 female, FMNH); same locality, ix.1920 (1 male, FMNH) ; Santo Amaro , xii.1962, J. Lane (1 male, CNC) ; S~ ao Paulo , 14.i.1915, A. Bierig (2 males, 1 female, FMNH) ; same locality ii.1923 (1 female, CNC) . PARAGUAY: Itapúa: San Pedro Mi, San Rafael Reserve , -26.5233 -55.8050, FIT, 27–30.xi.2000, Z. H. Falin (1 male, SEMC) .

Diagnosis. Dysanellus transverserugosus can be easily distinguished from D. bruchi based on the rugose sculpture ( Fig. 6 ) on the head and pronotum on D. transverserugosus . Ocyolinus rugatus Sharp (illustrated in Chatzimanolis and Ashe 2009) appears superficially similar to D. transverserugosus due to the rugose sculpture of the forebody, but these two species can be easily distinguished from each other by the shape of the last labial palpomere, the presence or absence of the postcoxal process, and the completely different shape of the aedeagus.

Description. Body length 14.1–17.6 mm. Head and pronotum dark metallic brown with purple overtones, elytra metallic golden brown. Mouthparts, mesoscutellum, ventral surface of body, and legs brown; antennomeres 1–6 brown, 7–11 dark orange. Abdominal segment VIII orange-brown. Head transverse, width:length ratio = 1.39; posterolateral corners slightly expanded. Epicranium with transverse rugose sculpture and dense, small punctures; distance between punctures equal to width of puncture; with polygonal microsculpture visible in areas not covered by punctures. Eyes small to medium-sized, length of eyes / length of head ratio = 0.36, distance between eyes as wide as 2.69 times length of eye. Mandibles with long medial tooth. Distal margin of labial palpomere 3 bent, not straight. Antennomeres 1–9, 11 longer than wide; antennomere 10 subquadrate. Neck with microsculpture and dense micropunctures. Pronotum quadrate, width:length ratio = 1.00; surface of pronotum with stark transverse rugose sculpture; with uniform, dense, small punctures in multiple rows, but rows hard to see due to rugose sculpture; with sparse microsculpture; pronotum shiny. Elytra with small to medium-sized, punctures (about 12–14 punctures / elytral width); distance between punctures equal to width of puncture. Elytra shiny; with sparse microsculpture. Abdominal terga III–IV without subbasal (arch-like) carina. Male secondary sexual structures ( Fig. 13 ) on sternum VII with broad, shallow emargination medially; presence of porose structure on sternum VII unclear; sternum VIII with U-shaped emargination medially; sternum IX with deep V-shaped emargination medially. Female without obvious sexual structures. Aedeagus as in Figs. 16–18 ; in dorsal view, paramere wide, converging to emarginate tip; paramere shorter and narrower (apically) than median lobe; in lateral view, paramere slightly concave, narrower apically; paramere with peg setae along lateral margins near apex. Median lobe in dorsal view wide, converging to rounded apex, with a large tooth apically; in lateral view, becoming much narrower near apex.

Distribution. Known from the states of Minas Gerais, Rio de Janeiro, and S~ ao Paulo in Brazil and the department of Itapúa in Paraguay.

Remarks. It is unclear if there is a porose structure on sternum VII in males. While there is a general area in the middle of the anterior margin that is lighter in color and not covered by setae, there is no visible pore or specialized setae as in Torobus ( Figs. 14–15 ) or in other Xanthopygina (e.g., Chatzimanolis 2013, 2015a, b).

Figures

Figs. 1–2. Dysanellus species, habitus. 1) D. bruchi, total length = 15.2 mm; 2) D. transverserugosus, total length = 17.4 mm.

Figs. 5–6. Heads and pronota of Dysanellus species. 5) D. bruchi; 6) D. transverserugosus. Not to scale.

Figs. 9–10. Head, ventral view. 9. Dysanellus transverserugosus; 10) Torobus laetipes. Not to scale.

Figs. 11–12. Distal end of labial palpomere 3 in Dysanellus species. 11) D. bruchi; 12) D. transverserugosus. Scale bar = 50 µm.

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. 16–18. Aedeagus of Dysanellus transverserugosus. 16) Dorsal view; 17) Lateral view; 18) Paramere, ventral view.

Fig. 25. Distribution map of Dysanellus bruchi and Dysanellus transverserugosus.