Anthracus brevipennis, Jaeger, 2017

Jaeger, Bernd, 2017, Five new species of the Anthracus annamensis group from the Philippines and India (Coleoptera, Carabidae, Harpalini, Stenolophina), Linzer biologische Beiträge 49 (1), pp. 585-608 : 594-598

Anthracus brevipennis nov.sp. ( Figs 18-26 )

T y p e m a t e r i a l: Holotype: 3 ( MCZ) labelled "Plains of / NE Leyte Is., P.I. / Nov '44-Jan '45 / Darlington" and " HOLOTYPE 3 / Anthracus / brevipennis nov.sp. / des. B. Jaeger 2017".

Paratypes: 733, 2♀♀ (MCZ, cJAE) with same locality label as the holotype, 13 also with the label "det. Darlington / at B.M. 1947-48 / Notes p.". All paratypes additionally labelled " PARATYPE 3 or ♀ / Anthracus / brevipennis nov.sp. / des. B. Jaeger 2017".

E t y m o l o g y: The species name refers to the comparatively short elytra.

D e s c r i p t i o n: General appearance as figured ( Fig. 18 ). Body length 4.0- 4.6 mm (HT 4.3 mm); width 1.7-1.9 mm.

Shiny, pronotum weakly, elytra moderately iridescent. Upper surface mainly blackish brown to almost black, with clypeus, labrum and mandibles (inner margins and apices of the latter blackish), lateral margins, base and baso-lateral impressions of pronotum, lateral margin and first interval of elytra paler to darker reddish brown. Legs, palpi and first two antennomeres pale yellowish brown, remaining antennomeres more or less distinctly infuscated. Ventral surface mainly dark or dark reddish brown, but prosternum, often also metasternum, posterior margins of abdominal sternites and epipleura slightly paler.

Head ( Figs 18-20 ) including eyes rather narrow (HW/PW: 0.66-0.69), with eyes moderately prominent (head 1.53-1.63 times as wide as head between eyes). Labrum slightly rounded at apical margin. Mandibles medium sized, not distinctly prolonged and curved, left mandible moderately sharp at apex, not thickened or truncate. Antennae rather short relative to pronotal length (AL/PL: 2.07-2.27), and moderately long relative to elytral length (AL/EL: 0.74-0.85). Microsculpture on labrum almost isodiametric, on clypeus weakly transverse, on anterior half of head obliterated, or with traces of lightly to very lightly impressed isodiametric meshes, and on posterior half posterior to eyes with lightly impressed isodiametric meshes, becoming moderately transverse in front of pronotal anterior margin.

Pronotum ( Figs 18-20 ) moderately transverse, 1.27-1.34 times as wide as long, 1.44-1.52 times as wide as head, widest in second quarter, lateral seta inserted somewhat posterior to beginning of second quarter. Apical margin clearly emarginate with anterior angles moderately projecting forward and narrowly rounded at tips. Sides markedly rounded to anterior angles, from widest point rectilinearly narrowed to posterior angles, or very faintly sinuate in front of the latter, which are more or less well marked, and more or less widely rounded at tips. Basal margin almost rectilinear medially, slightly to moderately oblique to posterior angles. Lateral furrows evenly narrow anterior to lateral seta, and posterior to the latter first gradually, later markedly widened, and fused with the basolateral impressions. Baso-lateral impressions rather large and deep, markedly prolonged forward along sides, clearly and obliquely delimited from pronotal disc and median part of base, flattened to basal and lateral margin, that latter is somewhat reflexed. Basolateral impressions and other parts of pronotal surface impunctate. Median line fine, disappearing before reaching basal and apical margins. Anterior transverse impression obliterated. Microsculpture on disc with traces of lightly impressed dense and strongly transverse meshes, at baso-lateral impressions and lateral furrows with moderately impressed moderately transverse meshes.

Elytra ( Fig. 18 ) rather short, 1.44-1.51 times as long as wide, 2.61-2.79 times as long and 1.35-1.43 times as wide as pronotum, with sides almost parallel or weakly widened posteriad, widest about at middle. Subapical sinuation weak to moderate, apical tip of each elytron narrowly rounded. Elytral striae distinctly impressed and impunctate, scutellar striole moderately long. Intervals slightly convex on disc, becoming very slightly narrowed and moderately convex at apex. Basal pore at beginning of scutellar striole present, interval 3 in third quarter with one setiferous pore, adjoining stria 2. Microsculpture on scutellum isodiametric, on elytral intervals only occasional traces of very lightly impressed transverse lines rudiments visible. Macropterous.

Metepisterna at inner margin about 1.4 times longer than wide at basal margin. Prosternum medially with 5-6, and in front of apical margin with a row of 6 longer setae. Prosternal process posteriorly with 1 long, distinct seta. Abdominal sternite IV smooth or with few single setae, sternites V-VI with distinct and moderately dense pubescence. Last visible abdominal sternite of males and females almost rectilinear at apex, at apical margin with 4 longer setae in both sexes.

Protarsomeres 1-4 of males markedly dilated and with distinct, biseriately arranged adhesive hairs on ventral surface. Protarsomere 4 markedly bilobed. Mesotarsomeres 1-4 of males moderately dilated and with adhesive hairs on ventral surface, mesotarsomere 4 weakly bilobed. In females pro- and mesotarsomeres unmodified. Male profemora somewhat thickened in relation to females, but without a row of numerous long and fine setae at upper inner margin.

Median lobe of aedeagus ( Figs 21-26 ) rather large, with apical portion rather long and gradually converging to the narrowly rounded apex ( Figs 24-25 ). In lateral aspect only slightly curved ventrad with apical portion more or less straight ( Figs 21-23, 26 ), and apical tip with peculiar shape ( Fig. 22a ). Internal sac (lateral aspect) composed of 1 medium sized and 1 large subapical teeth, followed by a group of 2 larger and 7-8 smaller teeth, arranged dorsally, and ventrally with 1 or 2 larger teeth at middle and 1 large elongate tooth basally, or in one specimen ( Fig. 22 ) additionally with 3 medium sized teeth between them.

C o m p a r i s o n s A. brevipennis n. sp belongs to the Anthracus annamensis group and represents the largest of the three immaculate species which are now known from the Philippines. It differs from these species and also from all other immaculate Oriental taxa of the species group by its peculiar habitus, with its broad body, the characteristic pronotal shape with large baso-lateral impressions, the quadrisetose anal sternite of males, and the specific and different shape of the median lobe, and internal structures of the aedeagus. From most species it can be also separated by the missing or strongly reduced pubescence of abdominal sternite IV.

D i s t r i b u t i o n A. brevipennis is so far known only from the Philippine island of Leyte. Because the species has fully developed hind wings it is probably more widely distributed, at least in the Philippines.

Figures

Figs 18-20: Anthracus brevipennis nov.sp. Habitus, head and pronotum. (18) HT, (19-20) PTs.

Figs 21-26: Anthracus brevipennis nov.sp. Median lobe of aedeagus, dorsal and lateral aspects. (21-25) PTs, (26) HT.