Anthracus novaecaledonicus, Auvel, 2016

Auvel, 2016, Two new species of the Anthracus annamensis group from Australia and New Caledonia, and notes on identity and generic placement of Acupalpus angulatus MACLEAY, 1871 and Acupalpus trapezus FAUVEL, 1882 (Coleoptera, Carabidae, Harpalini, Stenolophina, Pelmatellina), Linzer biologische Beiträge 48 (2), pp. 1295-1312 : 1299-1300

Anthracus novaecaledonicus nov.sp. ( Figs 9-14 )

T y p e m a t e r i a l: Holotype: 6 ( IRSNB) with original labels as figured ( Fig. 11 ) and " HOLOTYPE 6 / Anthracus / novaecaledonicus n.sp. / des. B. Jaeger 2016" [red label]. The holotype is in good condition with left antennomeres 4-11 missing.

E t y m o l o g y: The species name refers to the known distribution of the species.

R e d e s c r i p t i o n: General appearance as figured ( Fig. 9 ). Body length 4.2 mm; width 1.6 mm.

Shiny, pronotum weakly, elytra moderately iridescent. Upper surface almost black, with clypeus, labrum and mandibles (inner margins and apices blackish), medial part of pronotal basal margin, first elytral interval and apex paler to darker reddish or reddish brown. Antennomeres 1 and 2 pale reddish brown, 2-8 dark and 9-11 paler brown. Legs and palpi dark yellowish brown. Ventral surface with head (mouthparts reddish) pro-, meso and metasternum and elytral epipleura dark reddish brown, pro-, mes-, and metepisterna darker blackish brown, and ventrites blackish brown with apical margins of ventrites 3-5 narrowly, and of ventrite 6 widely paler brown.

Head ( Figs 9-10 ) including eyes 0.80 times as wide as pronotum, with eyes moderately prominent (head 1.55 times as wide as head between eyes). Labrum with apical margin almost rectilinear, but obliquely bent to right side. Mandibles medium sized, not distinctly prolonged and curved, left mandible markedly obtuse at apex, but not thickened or truncate. Antennae 2.33 times as long as pronotum and 0.82 times as long as elytra. Microsculpture on labrum isodiametric, on clypeus weakly transverse, on anterior half of head almost obliterated or with lightly impressed isodiametric meshes, on posterior half with lightly impressed isodiametric meshes, becoming weakly transverse in front of pronotal anterior margin.

Pronotum ( Figs 9-10 ) 1.30 times as wide as long, 1.25 times as wide as head, widest in second quarter, lateral seta inserted just posterior to beginning of second quarter. Apical margin markedly concave, anterior angles narrowly rounded at tips, moderately projecting forward. Sides convex in anterior half, rectilinearly narrowed to posterior angles, which are rather widely rounded. Basal margin weakly arcuate medially, slightly oblique to posterior angles. Lateral channels evenly narrow in apical two thirds, becoming markedly widened at posterior third, where they are fused with the baso-lateral impressions. Baso-lateral impressions medium sized, clearly delimited from pronotal disc and median part of base, fused with basal and lateral margin. Basal impressions and other surface of pronotum impunctate. Median line fine, disappearing before reaching basal and apical margins. Anterior transverse impression suggested. Microsculpture on disc almost obliterated, only here and there with very faintly impressed rudimentary lines and strongly transverse meshes, more distinct at medial part of base and in front of pronotal apical margin, at basal-lateral impressions with distinct isodiametric to weakly transverse meshes.

Elytra ( Fig. 9 ) 1.62 times as long as wide, 2.85 times as long and 1.35 times as wide as pronotum with sides very weakly widened posteriorly, widest at middle. Elytral striae distinctly impressed and impunctate, scutellar striole long. Intervals weakly convex on disc, becoming 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 almost isodiametric, on elytral intervals almost obsolete, only here and there traces of very lightly impressed transverse lines visible. Macropterous.

Metepisterna at inner margin about 1.5 times longer than wide at basal margin. Prosternum medially with 6-9, and in front of apical margin with 4-5 longer setae. Prosternal process posteriorly with at least 6 long and distinct setae. Ventrites 4-6 with distinct and rather dense pubescence, in ventrite 4 reduced laterally. Last visible ventrite of the male holotype weakly emarginated and at apical margin with two longer setae.

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 moderately bilobed. Male profemora somewhat thickened and with a row of 7-8 closely arranged long and fine setae at upper inner margin.

Median lobe of aedeagus ( Figs 12-14 ) large with apex very broad and widely rounded. Internal sac composed of three large apical/subapical teeth, and about 14 small to medium sized teeth whose arrangement is not yet clear, because of the partly everted internal sac.

C o m p a r i s o n s A. novaecaledonicus nov.sp. belongs to the Anthracus annamensis group according to the chaetotaxy of the ligula and the prosternum and other characters. Within this species group it is similar to species with immaculate elytra, particularly to A. furvus (ANDREWES) and A. wrasei JAEGER from the East Asian continent, and to A. furvinus (DARLINGTON) from Papua New Guinea. Though A. novaecaledonicus is close to these species in general appearance, it differs from them markedly, not only by the different shape and internal structures of the median lobe of the aedeagus, but also by the different shape and chaetotaxy of the male profemora. Regarding the latter characters, the species is similar and obviously closely related to A. furvinus from Papua New Guinea and to A. baehri from Australia. However, it can be separated from the former by the different shape and internal structure of the aedeagal median lobe, less numerous setae on male profemora and some body proportions, particularly those of the elytra, which are longer relative to width and longer relative to pronotal length. From A. baehri nov.sp. it can be easily distinguished by characters given under this species.

D i s t r i b u t i o n A. novaecaledonicus is known only from New Caledonia, Païta.

Figures

Figs 9-11: Anthracus novaecaledonicus nov.sp. Habitus, head and pronotum, original labels. (9-11) Holotype.

Figs 12-14: Anthracus novaecaledonicus nov.sp. Median lobe of aedoeagus, lateral and dorsal aspect. (12-14) Holotype.