Dysanellus bruchi Bernhauer, 1911

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 : 282-283

Dysanellus bruchi Bernhauer, 1911

( Figs. 1 , 5 , 11 , 25 )

Dysanellus bruchi Bernhauer 1911: 419 .

Type Material. Holotype, female, with labels: “Rep. Argentina, Prov. Buenos Aires, 11[xi].1896, C. Bruch ” / “ Trigonophorus bruchi n. sp. Fvl.” / “ Dysanellus bruchi Brh Typus” / “Chicago NHMus. M. Bernhauer Collection ”. In the collection of FMNH. A habitus photograph of the type appears in Chatzimanolis (2012).

Additional Material. ARGENTINA: Entre Rios: Pronunciamiento , ii.1975, Bolle (1 female CNC) ; Tucumán: 15 km N Tucumán, R´ıo Sali , 254m, 30.xii.1971, L. Herman (1 female, AMNH) ; Unknown province : O. W. Thomas, 1901-143 (1 female, BMNH) .

Diagnosis. Dysanellus bruchi can be easily distinguished from D. transverserugosus by the absence of rugose sculpture ( Fig. 6 ) on the head and pronotum of D. bruchi .

Description. Body length 13.6–16.1 mm. Head, pronotum, and elytra metallic green-blue. Mouthparts, mesoscutellum, ventral surface of body, and legs brown; antennomeres 1–5 brown, 6–11 dark orange. Posterior margin of abdominal segment VII and segment VIII orange-brown. Head transverse, width:length ratio = 1.44; with posterolateral corners slightly expanded. Epicranium with dense polygonal microsculpture and micropunctures; with medium-sized punctures around margin of head and eyes and with few other scattered medium-sized punctures on middle of epicranium. Eyes mediumsized, length of eyes / length of head ratio = 0.53, distance between eyes as wide as 1.94 times length of eye. Mandibles without long medial tooth. Distal margin of labial palpomere 3 straight, not bend. Antennomeres 1–7, 11 longer than wide; antennomere 8–10 subquadrate. Neck with microsculpture and few micropunctures. Pronotum quadrate, width:length ratio = 1.02; surface of pronotum uniformly covered with dense polygonal microsculpture and micropunctures; appearing matte due to microsculpture. Pronotum with one well-defined row of medium-sized punctures adjacent to each side of impunctate center line; with additional 3 diagonal rows of punctures (on each side), rows starting on anterolateral corners; distance between punctures varies, typically 2–3 times width of puncture. Elytra with small to mediumsized uniform punctures (about 14–16 punctures / elytral width); distance between punctures equal to width of puncture. Elytra shiny; with sparse microsculpture. Abdominal terga III–IV with faint subbasal (arch-like) carina. Female without obvious sexual structures. Males unknown.

Distribution. Known from the provinces of Buenos Aires, Entre Rios, and Tucumán in Argentina.

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

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