Anthracus sumatraensis Jaeger 2015, nov.sp.
Creators: name: Jaeger, Bernd
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Carabidae
Anthracus
Anthracus sumatraensis

description: Anthracus sumatraensis nov.sp.
(Figs 13-15, 50-55, 80)
Type material: Holotype: ♂ (NHMW) labelled " Indonesia 1990 / leg. Schillhammer "; " N-Sumatra / 16. 2. / n-Sibolga" and "HOLOTYPE ♂ / Anthracus / sumatraensis sp. n. / des. B. Jaeger 2015" [red label].
Paratypes: 2♂♂ (NHMW, cJAE) with same locality labels as the holotype and "PARATYPE ♂ / Anthracus / sumatraensis sp. n. / des. B. Jaeger 2015 " [red label].
Etymology: The species name refers to the known distribution of the species.
Description: General appearance as figured (Fig. 13). Body length 3.6-3.9 mm (HT 3.9); width 1.4-1.5 mm.
Shiny, pronotum slightly, elytra moderately iridescent. Head and pronotum reddish yellow, with clypeus, labrum, and mandibles (inner margins and apices blackish) weakly paler. Elytra with same ground colour as head and pronotum, with each elytron having a large, indistinct dark brown central macula, expanding laterally to interval 5, 6 or 7, and leaving base, apex and first interval reddish yellow. Legs and palpi pale yellowish brown, antennae with first two antennomeres yellowish brown, remaining ones weakly infuscated. Ventral surface mainly reddish brown, sometimes abdominal sternites and epipleura slightly paler.
Head (Figs 13-15) including eyes 0.81-0.83 times as wide as pronotum, eyes moderately prominent (head 1.59-1.65 times as wide as head between eyes). Labrum with apical margin linear but somewhat sloping down to the right side. Mandibles medium sized, left mandible rather sharp at apex, not thickened or truncate. Antennae moderately long, 2.52-2.62 times as long as pronotum and 0.90-0.92 times as long as elytra. Microsculpture on clypeus almost isodiametric, on labrum weakly transverse, on frons with very fine and lightly impressed and on vertex with moderately impressed isodiametric meshes becoming weakly transverse in front of pronotal apical margin.
Pronotum (Figs 13-15) 1.26-1.31 times as wide as long, 1.21-1.24 times as wide as head, widest in second quarter, lateral seta inserted a little posterior to beginning of second quarter. Apical margin almost rectilinear or very faintly emarginated, anterior angles narrowly rounded at tips, not or very weakly projecting forward. Sides convex in anterior half and rectilinearly narrowed to posterior angles, which are obtuse and moderately rounded. Basal margin weakly to moderately arcuate medially and oblique to posterior angles. Lateral furrows moderately wide anteriorly, becoming moderately widened in posterior third, where they are fused with the baso-lateral impressions. The latter medium sized and somewhat oblique, distinctly delimited from the pronotal disc and the somewhat depressed median part of base, fused with basal and lateral margins, the latter weakly reflexed. Anterior transverse impression obsolete, rarely suggested. Microsculpture on disc with lightly impressed, strongly transverse meshes, at baso-lateral impressions and lateral furrows with markedly impressed isodiametric meshes.
Elytra (Fig. 13) rather short, 1.53-1.57 times as long as wide, 2.75-2.91 times as long and 1.41-1.43 times as wide as pronotum. Sides moderately widened posteriorly, widest just posterior to middle. Subapical sinuation weak. Elytral striae distinctly impressed and impunctate, intervals rather flat, becoming weakly narrowed and weakly convex at apex. Microsculpture on scutellum and around basal pore isodiametric, on elytral intervals only with traces of very lightly impressed transverse lines.
Metepisterna long, distinctly narrowed posteriad, at inner margin about 1.5 times longer than wide at the basal margin. Prosternum medially with 6 and close to apical margin with a row of 6 medium long setae (often broken resulting in insertion points difficult to observe). Prosternal process with 1 distinct seta.
Pro- and mesotarsomeres 2-4 of males distinctly dilated. Protarsomere 4 markedly, mesotarsomere 4 weakly bilobed. Protarsomeres 1-4 and mesotarsomeres 2-4 of males with biseriately arranged adhesive hairs on ventral surface.
Median lobe of aedeagus (Figs 50-55) with general appearance as figured. Apical plateau with shape rather variable, moderately long and moderately narrowed to apex (dorsal aspect), the latter somewhat thickened, with no distinct hook (lateral aspect). Internal structures composed of 3 larger subapical teeth, 1-2 smaller teeth in medial portion and 1-2 smaller teeth in basal half.
Comparisons: Anthracus sumatraensis nov.sp. is the only maculate species so far known from Sumatra. It differs from A. nesophilus and A. javaensis nov.sp. from Java by characters given under these species. From A. siamensis nov.sp. which is the most closely distributed species from SE Asian mainland, A. sumatraensis can be separated by the different external shape and internal structures of the median lobe of the aedeagus (Figs 50-55, 63-67, 69-73), the elytra, which are broader relative to pronotum (ratio EW/PW>1.40, in A. siamensis <1.39), and the colour of head and pronotum which is usually paler and/or the elytral macula which are only indistinct and not clearly marked as in A. siamensis.
Distribution A. sumatraensis nov.sp. is so far known only from the type locality in northern Sumatra (Fig 80).
description: Published as part of Jaeger, Bernd, 2015, Revision of the maculate species of the Anthracus annamensis group from the East Palaearctic and Oriental Regions. Part 2. A redescription of Anthracus nesophilus (ANDREWES, 1936) and six new species from Nepal, India and SE Asia (Coleoptera, Carabidae, Harpalini, Stenolophina), pp. 1361-1396 in Linzer biologische Beiträge 47 (2) on pages 1369-1371, DOI: 10.5281/zenodo.5193661