Atrotus indicus, Guéorguiev, Borislav, 2013

Guéorguiev, Borislav, 2013, Taxonomic, nomenclatural, and faunistic records for species in tribes Melaenini, Moriomorphini, Pterostichini, Licinini, and Sphodrini (Coleoptera: Carabidae), Zootaxa 3709 (1) : -

Atrotus indicus sp. n.

Habitus: Fig. 16 ; mouth parts: Fig. 17 ; male genitalia: Figs. 18–20 .

Type material. Holotype ♂, left fore leg missing, mounted on card, genitalia dissected and deposited in euparal on separate triangular card pinned below the first card, “ INDIA: Tamil Nadu Nilgiri Hills Coonoor, 1700 m, 3.– 5.10.1991 leg. R. SCHUH ” [black print on white label] / “H O L O T Y P E Atrotus indicus sp. nov. Guéorguiev des. 2012” [black print on red label] [ Fig. 16 ] ( NMW).

Diagnosis. This species is easily diagnosed from all congeners by the following set of characters: 1/ size of body 7.5 mm; 2/ microsculpture distinct on the whole dorsal surface; 3/ terminal segment of the maxillary palpi attenuate; 4/ pronotum widest around the middle, with plane lateral margins; 5/ elytral striae impunctate; 6/ parascutellar stria absent; 7/ median lobe with disc at apex.

Description. Habitus. Moderately large-sized species of Atrotus , with elongate and flat body. Measurements. BL: 7.5 mm; BW: 2.95 mm. Ratios. PW/HW: 1.73; PW/PL: 1.29; PbW/PaW: 1.36; EW/PW: 1.31; EL/EW: 1.54. Color. Head piceous, with base of clypeus, mandibles and most of terminal segments of maxillary and labial palpi testaceus, apex of clypeus, labrum, palpi, and antennae yellowish; pronotum piceous on disc and apex, sides and base narrowly testaceus; elytra dark brown to piceous on disc and base, apex and fields outside stria 8 testaceus to yellowish, scutellum and suture somewhat darker than disc; ventral side mostly dark brown to piceous, mouthparts testaceous, elytral epipleura and entire legs yellowish. Microsculpture. Distinct on entire dorsal surface, head and pronotum with isodiametric, elytra with slight transverse microsculpture. Lustre. Dorsal and ventral surfaces shiny. Head. Narrower with respect to pronotum, frons smooth, frontal furrows superficial, short, converging behind, two supraorbital setae on each side; eyes fairly large, convex, moderately prominent, tempora short; clypeus incompletely fused with labrum, with anterior margin almost straight and a seta on each side, same incompletely fused with frons as clypeal suture is perceptible; labrum fairly bilobed, with V-shaped incision in middle, incision with two short setae medially, lobes inflated, each with a large seta at apex; mandibles long, curved downwards at apex, incisor tooth and terebral tooth sharp-pointed (angle at tip <90º) in both mandibles, as incisor teeth longer, more curved and sharper than terebral teeth ( Fig. 17 ); apical segments of maxillary palpi attenuate, sparsely pubescent; apical segment of labial palpi somewhat fusiform, sparsely pubescent; antennae very long, basal antennomere almost as long as two succeeding segments, antennomere 7 crosses posterior margin of pronotum. Pronotum. Wide, sub-quadrate, widest at middle, with lateral margins distinctly, narrowly bordered (bordering reduced only before posterolateral setae), flat; sides more convex apically than basally, with two pairs of setae situated inward at discal position (not at margin), lateral setae situated in pronotal apical second fifth, removed from border at a distance larger than diameter of pore, posterolateral setae situated in pronotal basal sixth before hind angles, at distance from border equal to diameter of pore; anterior margin emarginated, shorter than basal margin, fore angles round, moderately prominent; posterior margin convex, hind angles broadly rounded, without perceptible tips; basal impressions rather faint, sub-linear, slanting, convergent posteriorly; disc flat, smooth (only basal part with several faint and short longitudinal wrinkles), median line short, fine, faintly impressed. Elytra. Sub-elongate, widest just after middle, coalesced along suture; sides with very slight subapical sinuation; humeri well-marked, obtusely angulate; striae impunctate, moderately impressed, parascutellar striae absent, all striae disappeared close to base; intervals flat, smooth; basal margin complete, almost reaching stria 1; parascutellar setiferous puncture present, situated in stria 2; interval 3 with a small discal setiferous puncture adjoining stria 2 at basal second fifth of elytra; hind wings vestigial. Ventral surface (thorax and abdomen). Sternal part of thorax and abdomen smooth and shiny; metepisterna very wide, shorter than long, weakly narrowed behind, anterior margin appreciably longer than each of other three margins; last visible sternum with two minute marginal setiferous punctures. Legs. Long, slender; basal segments 1–3 of male protarsi dilated and asymmetrical, first one longer than wide, longer than each of two succeeding segments, segments 2–3 nearly as long as wide. Male genitalia. Median lobe of aedeagus moderately long, curved down viewed laterally ( Fig. 18 ), basal and medial parts uniformly wide, basal orifice rather concave, apical part thinner towards hooked tip (dorsal hook larger, ventral hook minute); right paramere long and narrow, dilated at tip with a minute seta ( Fig. 19 ), left paramere conchoid, with a minute seta in distal position ( Fig. 20 ).

Affinities. The morphologic features of the new species conform rather well to the extended diagnosis of Atrotus ( Basilewsky 1951) . However, there are two features with different states in the new taxon, compared with those in the other congeners: 1/ terminal segment of the maxillary palpi attenuate (not fusiform); 2/ complete reduction of the parascutellar striae of the elytra.

Based on Britton (1948) and Basilewsky (1951), A. indicus sp. n. appears close to two species, one from the Arabian Peninsula and another from South Africa. The new species resembles Atrotus bicolor Britton, 1948 from Yemen in the pronotum widest near to the middle, with sides rectilinear to hardly convex towards the base, and elytra with impunctate striae and smooth intervals. But the former is distinct from latter, in: 1/ larger size of body (7.4. mm in A. indicus sp. n., vs. 6.5 mm in A. bicolor ); 2/ uniformly colored pronotum and elytra (vs. pronotum and elytra bicoloured in A. bicolor ); 3/ microsculpture distinct on the whole dorsal surface (vs. microsculpture absent on the pronotum and disc of elytra in A. bicolor ); 4/ pronotum with sides and base narrowly testaceus, apex and disc piceous (vs. sides, apex and base broadly testaceus, disc piceous in A. bicolor ); 5/ lateral margins of pronotum completely flat (vs. lateral margins “slightly but broadly reflexed behind” in A. bicolor ); 6/ base and disc of elytra dark brown (vs. base of elytra testaceous, disc piceous in A. bicolor ).

On the other hand, there is similarity in the microsculpture of pronotum and elytra, as well as, shape of aedeagus of the new species ( Fig. 18 ) to that of A. fortipatus Péringuey ( Basilewsky 1951: 8, Fig. 2 ), the latter being the type species of the genus which inhabits the provinces of Western Cape and Eastern Cape of the Republic of South African. However, the former is distinct from the latter in: 1/ the almost symmetrical lobes of labrum (highly asymmetric in A. fortipatus ); 2/ pronotum widest around the middle (vs. pronotum widest before the middle in A. fortipatus ); 3/ sides of pronotum rectilinear to hardly convex towards the base (vs. sides slightly sinuate towards the base in A. fortipatus ); 4/ moderately impressed elytral striae (vs. striae deep in A. fortipatus ); 5/ elytral intervals flat (vs. intervals more or less convex in A. fortipatus ).

Distribution. India, state Tamil Nadu, Nilgiri Hills Mountain, the vicinity of Coonoor Town, around 1700 meters above sea level.

Etymology. The specific epithet is a noun in the nominative singular in preposition. It honors India, the country where the new species was collected.

Figures

FIGURES 16 – 20. Holotype of Atrotus indicus sp. n.: Fig. 16, habitus (photo by Assen Ignatov); Fig. 17, mouthparts, dorsal aspect; Fig. 18, median lobe of aedeagus, lateral aspect; Fig. 19, right paramere, internal face; Fig. 20, left paramere, internal face. Scale bars: 0.5 mm (Fig. 17); 0.2 mm (Figs. 18 – 20).

FIGURES 2 – 6. Holotype of Mecyclothorax baehri sp. n.: Fig. 2, habitus; Fig. 3, median lobe of aedeagus, left lateral aspect; Fig. 4, right paramere; Fig. 5, left paramere; Fig. 6, urite, dorsal view. Scale bars: 1.5 mm (Fig. 2); 0.5 mm (Figs. 3 – 6).