Homalotrichus shapra Pérez, Rodríguez & Asenjo, 2018

Pérez, Luis, Rodríguez, Maryzender & Asenjo, Angélico, 2018, Two new species of Homalotrichus Solier, 1849 (Coleoptera: Staphylinidae) from Peru, Zootaxa 4459 (2), pp. 376-386 : 382-385

Homalotrichus shapra Pérez, Rodríguez & Asenjo , sp. nov.

( Figs. 6A–J )

Type material (3♂♂, 3♀♀). Holotype: PERU: ♂, labeled “ PERU: CA[Department of Cajamarca], Rio Chonta, / Cerro Negro , 7°0'29.79"S, / 78°34'44.55"W, 3656 m [altitude in relation to sea level], / 29-30.xi [November].2010. F. Chávez / leg.”; “ HOLOTYPE [red label] / Homalotrichus shapra / Pérez, Rodríguez & Asenjo / Desig. / Pérez et al., 2018” ( MUSM) . Paratypes (5): 2♂♂, 1♀, labeled “ PERU: CA[Department of Cajamarca], Caserio / Chugurmayo, 6°53'38"S, / 78°19'4.9"W, 3626 m [altitude in relation to sea level], / 20.xi [ November ].2012” (1♂ and 1♀ MUSM; 1 ♂ FMNH) . 2♀♀, labeled “ PERU: CA[Department of Cajamarca], Rio Chonta, / Cerro Negro , 7°0'29.79"S, / 78°34'44.55"W, 3656 m [altitude in relation to sea level], / 29-30.xi [November].2010. F. Chávez / leg.” ( MUSM); all paratypes labeled “ PARATYPE [yellow label] / Homalotrichus shapra / Pérez, Rodríguez & Asenjo / Desig. Pérez et al., 2018”.

Diagnosis. H. shapra sp. nov. is easily differentiated from other species of Homalotrichus by the combination of the following characters: head width about 8× eye width ( Fig. 6A,C ), pronotum convex, lateral margin strongly convex and narrowing to base and pronotal impressions oval-shaped ( Fig. 6A,C ). The male is easily differentiated from males of other species by not having a marked sexual dimorphism: absence of triangular process on tergum VII ( Fig. 6A–B ) and the absence of a huge curved horn on tergite VIII.

Description. Holotype male (BL: 3.80; BW: 1.08).

Head, antennae, pronotum, and abdomen black, elytra dark brown. Mouthparts light brown, labial palps, maxillary palps dark brown. Coxae and trochanter dark brown. First to fifth tarsomeres brown ( Figs. 6A–B ).

Head hexagonal, wider than long (HW: 0.67; HL: 0.46) with anterior margin straight, head width about 8× eye width. Neck narrower than head (NW: 0.49). Cephalic disk ( Fig. 6A ) with micro-punctation spread heterogeneously forming smooth areas. One macroseta near anterior edge of eye, one macroseta near posterior edge of eye and one macroseta near posterior margin of head ( Fig. 6C ). Eyes large and prominent, longer than wide (YL: 0.184; YW: 0.08) located laterally in middle part. Antennae longer than length of head and pronotum together, antennomere 1 the longest, slightly incrassate apically, 2–3 elongate and strongly incrassate apically, 4 slightly longer than wide, antennomere 5 subquadrate, from 5 on broader than 2–4 and with distinct basal ridge, antennomere 10 wider than length (width:length = 0.14:0.13), terminal antennomere about 1.4× longer than wide.

Pronotum convex ( Figs. 6A–C ) wider than long (PW: 0.85; PL: 0.64), margin anterior slightly convex and posterior margin straight, lateral margin irregular, strongly convex and narrowing to base. Pronotal disc with setigerous punctures spread irregularly. Two pronotal impressions oval-shaped near posterior margin. Three macrosetae near each lateral margin and two setae near each posterior corner. Two pairs of macroseta near anterior margin. Two macrosetae near posterior margin. Scutellum subtriangular with rounded apex and with micropunctation ( Figs. 6A,C ).

Elytra ( Figs. 6A–C ) longer than wide (EL: 1.15; EW: 1.11) with apex wider than base. Elytron with five well defined lines of punctures and scattered punctures near outer lateral margin. First longitudinal line with five setae near inner lateral margin, line of seven setae near outer lateral margin, line of six setae very close outer lateral margin.

Legs. Procoxae conical narrowly separated by prosternal process. Mesocoxae contiguous, elongated and oblique, separated by mesosternal process. Metacoxae transversal, with conical region that articulates with trochanter. Protrochanter triangular, mesotrochanter triangular, and metatrochanter triangular. Profemora, mesofemora and metafemora long, mesofemora tapering slightly towards its extreme. Left protibiae with a defined row of four spines and two setae in external-lateral margin, right protibiae with well defined row of five spines and two setae in external-lateral margin, mesotibiae and metatibiae with spines. Tarsi 5-segmented, tarsomere 1–4 small, as long as wide (0.03:0.04). Tarsomere 5 longer than wide (0.20; 0.04).

Abdomen margined ( Fig. 6A ). Terga III-VII (morphological segments) with subbasal carinae complete. Segments III-VI with two laterosternites per segment, segment VII with only one laterosternite per segment. Tergum VII without a triangular process that is more or less lamellar at midline, near posterior margin. Tergum VIII emarginate, trapezoidal with 16 macrosetae, 6 arranged near each lateral margin and 4 macrosetae in middle forming a rectangle ( Fig. 6D ). Sternite VIII ( Fig. 6E ) with membranous lobe on posterior margin, 6 macrosetae in each lateral-posterior third. Tergum IX visible in ventral view, many setae in distal part (dorsal view). Sternite IX an elongate plate.

Aedeagus symmetrical, with median lobe bulbous at base, narrow in middle part. Parameres thin, curved, not exceed length of aedeagus. In ventral view ( Fig. 6F ), parameres fused basally. In lateral view ( Fig.6G ), parameres with acute projection near base. In dorsal view ( Fig. 6H ), base of median lobe with an oval membranous area. Internal sclerites as in Figs. 6F–H .

Female similar to male, except sternite IX ( Fig. 6J ) divided perpendicularly and forming two plates with many setae in distal part and absence of acute projection in tergum IX ( Fig. 6I )

Habitat. Unknown.

Distribution. Known from Chugurmayo and Cerro Negro localities, Cajamarca, northern region of Peru, at 3626 m and 3656 m respectively ( Fig. 7).

Etymology. The specific name “ shapra ” means hair in Quechua. It refers to the large number of setae on sternite VIII. This is a noun in apposition.

Remarks. The number of spines on the protibiae varies between 4 – 5 in the paratypes.

Figures

FIGURE 6. (A–J) (A–H) Homalotrichus shapra sp. nov., holotype male: (A) habitus, dorsal view; (B) habitus, lateral view; (C) arrangement of setae on head, pronotum and elytra; (D) male tergum VIII (T8); (E) male sternite VIII (S8); (F), aedeagus, ventral view; (G) aedeagus, lateral view; (H) aedeagus, dorsal view. (I–J) Homalotrichus shapra sp. nov., paratype female from Cajamarca, Cerro Negro: (I) female tergum IX (T9) and tergum X (T10), dorsal view; (J) female tergum IX (T9) and sternite IX (S9), ventral view. Dotted areas (E–J) represent membranous areas. Circles in (D) represent the external opening of spiracles. Arrows in (I) indicate the external opening of abdominal glands.