Limonius onyx Arimoto & Suzuki 2020, sp. n.
Creators: name: Arimoto, Kôichi
name: Suzuki, Wataru
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Elateridae
Limonius
Limonius onyx

description: Limonius onyx Arimoto & Suzuki, sp. n.
(Figures 5, 6, 7B)
Etymology. In reference to the dark and shining body like onyx jewelry.
Type material. Holotype. Male (LOA001), Shenmu Village, Xinyi Township, Nantou County, Taiwan, 8 V 1977, Shûsei Saitô leg.
Male. Diagnosis. Body surface without metallic luster; elytra interspaces between punctures smaller than puncture diameter. Body black. Frons in profile slightly depressed apically; supra-antennal carina in dorsal view broadly rounded, but slightly emarginate apically. Antennae extending beyond pronotum posterior lateral apices by apical two antennomeres; antennomere III slightly longer than II; IV distinctly longer than wide, longer than II–III combined, longer than V. Prothorax widening posteriad; lateral carina of prothorax strongly prominent just behind anterior angles. Anterior lobe of prosternum in profile weakly inclined. Mesial edge of hypomeron carinate anterolaterad. Prosternal spine without distinct subapical tooth; sides at ventral view roundly expanded and anteriorly strongly prominent. Scutellum longer than wide, weakly elevated medially; posterior margin broadly rounded, but emarginate medially. Mesepisternum not reaching mesocoxal cavity.
Measurements. BL: 6.97, BW: 1.95, MIE: 0.76, MAE: 1.08, OI: 141, PL: 1.85, PML: 1.78, PW: 1.72, PI: 107, EL: 4.69, EW: 1.95, EI: 240, BI: 254.
Description. Body surface shining and without metallic luster, generally smooth but elytra rough; dorsal inter- spaces between punctures smaller than puncture diameter; ventral interspaces between punctures generally larger than puncture diameter, but in hypomeron, anterior lobe of prosternum and prosternal spine interspaces between punctures smaller than puncture diameter (Fig. 5, F, H). Color. Body black (Fig. 5A, B). Mandible black, but apical part orange. Legs black, but partly with orange tinge; claws orange. Tergites and sternites VIII‒X and aedeagus yellow-brown, but terigite and sternite VIII colorless in basal median area (Fig. 6A, B). Pubescence. Body covered with orange setae dorsally, with white setae ventrally. Antennae with yellow to brown setae. Setae of legs white becoming yellow apically.
Head depressed longitudinally medially; the depression becoming narrow and shallow posteriad (Fig. 5C, D). Frons in profile slightly depressed apically (Fig. 5E: green line); supra-antennal carina in dorsal view broadly rounded, but slightly emarginate apically (Fig. 5C), in profile strongly prominent anteriad above clypeus (Fig. 5E: arrow). Antennae extending beyond pronotum posterior lateral apices by apical two antennomeres (Fig. 5A); antennomeres I and IV–XI longer than wide; II globular, shortest; III obconical, slightly longer than II; IV–X serrate; IV 1.12 x as long as wide, longer than II–III combined, 2.06 x as long as III, longer than V; XI 2.70 x as long as wide. Mandible bidentate.
Prothorax trapezoidal, longer than wide, widening posteriad; side weakly rounded; lateral carina extending from anterior angles to hind angles of prothorax, strongly prominent just behind anterior angles (Fig. 5C: arrow). Pronotum posteriorly with a shallow median longitudinal depression; hind angles broad, rounded, unicarinate; the carina short, extending to the base. Hypomeron: mesial edge with elevated impunctate ridge next to pronotosternal suture, carinate anterolaterad (Fig. 5F: black arrow); posterior margin without large emargination, weakly sinuate. Anterior lobe of prosternum slightly exceeding anterior angles of prothorax (Fig. 5B), in profile weakly inclined (at 24 degrees against prosternal horizontal line, Fig. 5E: red line). Prosternal spine in profile strongly inclined (at 23 degrees against prosternal horizontal line, Fig. 5G: red line); ventral margin in profile without distinct subapical tooth and sinuate; lateral lobe in profile with ventral margin straight apically (Fig. 5G: yellow line), at ventral view with sides roundly expanded and anteriorly strongly prominent (Fig. 5H: arrows); apical margin at ventral view rounded, with weakly prominent apex (Fig. 5H). Pronotosternal sutures not grooved, anteriorly opened and appearing double (Fig. 5F: white arrow). Scutellum 1.30 x as long as wide (Fig. 5I), weakly widening posteriad, widest near posterior 2/5, weakly elevated medially (Fig. 5G: arrow), moderately inclined anterior-downwards; anterior margin almost transverse; posterior margin broadly rounded, but emarginate medially (Fig. 5I: arrow). Mesosternum with a median longitudinal carina posterior to mesosternal cavity; borders of mesosternal cavity sinuate followed by strongly declivous (Fig. 5H: green line). Mesepisternum not reaching mesocoxal cavity. Mesepimeron with shallow depression for reception of femora of mid-leg. Metasternum sulcate medially and behind mesocoxae. Elytral striae distinctly grooved. Tarsomeres simple.
Abdomen with external margin micro-serrated (Fig. 5J); ventrite V 0.57 x as long as wide. Sternite VIII with median notch rounded (Fig. 6B). Tergite IX 1.22 x length of tergite X (Fig. 6C). Tergite X 1.12 x as long as wide (Fig. 6C). Sternite IX transverse apically (Fig. 6D). Aedeagus (Fig. 6E, F). Basal piece 0.38 x total length of aedeagus. Median lobe exceeding apices of parameres; basal struts 0.30 x total length of median lobe. Parameres separated ventrally; apex beyond lateral subapical barb wider sub-triangular (Fig. 7B), rounded apically, without setae.
Female. Unknown.
Comparative notes. This species is distinct from the congeners by the whole black body without metallic luster and with dense punctures. It is similar to L. ignicollis in having the following characters: elytra interspaces between punctures smaller than puncture diameter; supra-antennal carina in dorsal view broadly rounded, but more or less emarginate apically, in profile strongly prominent anteriad above clypeus; antennae extending beyond pronotum posterior lateral apices by apical two antennomeres; antennomere III slightly longer than II, longer than II–III combined, longer than V; prothorax widening posteriad; lateral carina of prothorax strongly prominent just behind anterior angles; mesial edge of hypomeron carinate anterolaterad; sides of prosternal spine at ventral view roundly expanded and anteriorly strongly prominent; scutellum longer than wide; posterior margin of scutellum broadly rounded, but emarginate medially. However it is distinguished by the following contrasting characters (L. ignicollis in parentheses): body surface without metallic luster (body surface with metallic luster); frons in profile slightly depressed apically (frons in profile weakly depressed apically); antennomere IV distinctly longer than wide (antennomere IV shorter than wide); anterior lobe of prosternum in profile weakly inclined (anterior lobe of prosternum in profile strongly inclined); prosternal spine without distinct subapical tooth (prosternal spine with subapical tooth); scutellum weakly elevated medially (scutellum strongly convex).
Distribution. Taiwan: Nantou County.
description: Published as part of Arimoto, Kôichi & Suzuki, Wataru, 2020, First record and two new species of the genus Limonius Eschscholtz (Coleoptera Elateridae, Dendrometrinae) from Taiwan, pp. 89-104 in Zootaxa 4742 (1) on pages 96-100, DOI: 10.11646/zootaxa.4742.1.5, http://zenodo.org/record/3674493