Anthracus darlingtoni, 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 : 586-590

publication ID	https://doi.org/ 10.5281/zenodo.5357351
persistent identifier	https://treatment.plazi.org/id/A71F87B6-E151-7662-FF5E-75A3FDDAFCCE
treatment provided by	Marcus
scientific name	Anthracus darlingtoni
status	sp. nov.

Treatment

Anthracus darlingtoni View in CoL nov.sp. ( Figs 1-7 View Figs 1-3 View Figs 4-8 , 9-12 View Figs 9-14 )

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"; "square – impunct. / det. Darlington / at B.M. 1947-48 / Notes p."[first line hw] and " HOLOTYPE 3 / Anthracus / darlingtoni nov.sp. / des. B. Jaeger 2017" [red label].

Paratypes: 333, 3♀♀ (MCZ, cJAE) with same locality label as the holotype, and additionally labelled " PARATYPE 3 or ♀ / Anthracus / darlingtoni nov.sp. / des. B. Jaeger 2017" [red label].

E t y m o l o g y: The species is named in memory of P. J. Darlington, Jr., famous carabidologist and zoogeographer, who collected this and other new species in the Philippines.

D e s c r i p t i o n: General appearance as figured ( Fig. 1 View Figs 1-3 ). Body length 3.7-4.2 mm (HT 4.2 mm); width 1.5-1.7 mm.

Shiny, pronotum weakly, elytra moderately iridescent. Head blackish brown or dark reddish brown, with clypeus paler reddish brown, and labrum and mandibles (inner margins and apices of the latter blackish) reddish yellow or yellowish brown. Pronotum blackish brown, dark brown or dark reddish brown, with lateral margins and hind angles, often also base and apical margin paler. Elytra blackish brown to almost black leaving base, apex, lateral margin and first interval paler reddish. Legs, palpi and first two antennomeres pale yellowish brown, remaining antennomeres slightly infuscated. Ventral surface with pro- and metasternum, epipleura and posterior margins of abdominal sternites paler reddish brown, other parts blackish brown.

Head ( Figs 1-3 View Figs 1-3 ) including eyes moderately broad (HW/PW: 0.72-0.78), with eyes moderately prominent (head 1.61-1.70 times as wide as head between eyes). Labrum slightly rounded at apical margin. Mandibles medium sized, not markedly prolonged and curved, left mandible moderately sharp at apex, not thickened or truncate. Antennae moderately long relative to pronotal (AL/PL: 2.32-2.45) and elytral length (AL/EL: 0.78- 0.84). Microsculpture on labrum almost isodiametric, on clypeus weakly transverse, on anterior half of head obliterated, or partly with traces of lightly to very lightly impressed isodiametric meshes, and on posterior half with lightly impressed isodiametric meshes, becoming moderately transverse in front of pronotal anterior margin.

Pronotum ( Figs 1-3 View Figs 1-3 ) weakly transverse, 1.21-1.27 times as wide as long, 1.29-1.39 times as wide as head, widest in second quarter, lateral seta inserted about at beginning of second quarter. Apical margin moderately emarginate with anterior angles weakly to moderately projecting forward and narrowly rounded at tips. Sides weakly rounded to anterior angles, and from widest point rectilinearly narrowed to posterior angles, or very faintly sinuate in front of the latter, which are well marked and narrowly rounded at tips. Basal margin very slightly concave, almost rectilinear or weakly arcuate medially, slightly to moderately oblique to posterior angles. Lateral furrows evenly narrow or gradually widened in apical half, becoming markedly widened at posterior third, where they fuse with the baso-lateral impressions. Baso-lateral impressions medium sized, clearly delimited from pronotal disc and the somewhat depressed median part of base, flattened to basal and lateral margin, the latter slightly reflexed. Baso-lateral impressions and other parts of pronotal surface impunctate. Median line fine, disappearing before reaching basal and apical margins. Anterior transverse impression suggested or obliterated. Microsculpture on disc with lightly impressed strongly transverse meshes, at basolateral impressions and lateral furrows with clearly impressed isodiametric to weakly transverse meshes.

Elytra ( Fig. 1 View Figs 1-3 ) moderately long, 1.53-1.60 times as long as wide, 2.84-3.01 times as long and 1.47-1.55 times as wide as pronotum, with sides weakly to moderately widened posteriad, widest somewhat posterior to middle. Subapical sinuation moderate, apical tip of each elytron rather sharp and in some specimens denticulate. Elytral striae distinctly impressed and impunctate, scutellar striole long. Intervals rather flat to weakly 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 almost obsolete, only occasional traces of very lightly impressed transverse lines are visible. Macropterous.

Metepisterna at inner margin about 1.5 times longer than wide at basal margin. Prosternum medially with 5-6, and in front of apical margin with a row of 6-8 longer setae. Prosternal process posteriorly with 2 long and distinct setae. Abdominal sternites IV-VI with distinct and rather dense pubescence, in sternite IV often with a small smooth area laterally. Last visible sternite of males faintly concave at apex, and that of females almost rectilinear or very faintly convex, at apical margin with 2 longer setae in males and 4 in females.

Protarsomeres 1-4 of males markedly dilated and with distinct, biseriately arranged adhesive hairs on ventral surface. Protarsomere 4 moderately 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 numerous long and fine setae on the upper inner margin.

Median lobe of aedeagus ( Figs 4-7 View Figs 4-8 , 9-12 View Figs 9-14 ) very large, with apical portion rather long and narrow in dorsal aspect ( Figs 9-12 View Figs 9-14 ). In lateral aspect only slightly curved ventrad with apex curved dorsad ( Figs 4-7 View Figs 4-8 ). Internal sac (lateral aspect) composed of 1 large and 1-2 smaller subapical teeth, and in medial portion with one group of 1 larger and 6-8 smaller teeth arranged ventrally, and one group of 1 larger and 5 smaller teeth arranged dorsally.

C o m p a r i s o n s A. darlingtoni nov.sp. belongs to the Anthracus annamensis group and represents one of the three species with immaculate elytra which are now known from the Philippines. It is rather similar to A. mindanaoensis nov.sp. in general appearance (at least to one of the female paratypes) and in the internal structures of the aedeagus, but it differs from the latter markedly by the large size of the median lobe of the aedeagus with other shape in lateral aspect ( Figs 4-7 View Figs 4-8 , 12 View Figs 9-14 respectively 8, 14), particularly of the apex (7a, 8a). Externally A. darlingtoni can be separated from A. mindanaoensis by larger size (with a small overlap), broader elytra and pronotum, and related proportions (e.g. EW/PW and PW/HW). However, the variation range of these characters is not yet clear, and therefore more material, particularly of A. mindanaoensis , is needed to verify these differences. From A. brevipennis nov.sp. which occurs sympatrically at the type locality "Plains of NE Leyte " it can be distinguished at a first glance by the completely different habitus ( Fig. 1 View Figs 1-3 , 18 View Figs 18-20 ), but also by the extended pubescence of abdominal sternite IV (smooth, or only with single hairs in A. brevipennis ), and the different size, shape and internal structures of the aedeagus.

From all other immaculate Oriental species of the A. annamensis group which occur in India, continental SE Asia and the Sunda Islands, A. darlingtoni can be easily separated by its different habitus, and the shape and internal structures of aedeagus.

D i s t r i b u t i o n A. darlingtoni 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.