Limonius onyx Arimoto & Suzuki, 2020

Arimoto, Kôichi & Suzuki, Wataru, 2020, First record and two new species of the genus Limonius Eschscholtz (Coleoptera Elateridae, Dendrometrinae) from Taiwan, Zootaxa 4742 (1), pp. 89-104 : 96-100

publication ID	https://doi.org/ 10.11646/zootaxa.4742.1.5
publication LSID	lsid:zoobank.org:pub:3016F563-FDAC-44FD-B6A5-44E1E8DFCFB4
DOI	https://doi.org/10.5281/zenodo.3681227
persistent identifier	https://treatment.plazi.org/id/FC3C87A4-327B-B31B-83CE-BE80BD70FF29
treatment provided by	Plazi
scientific name	Limonius onyx Arimoto & Suzuki
status	sp. nov.

Treatment

Limonius onyx Arimoto & Suzuki , sp. n.

( Figures 5 View FIGURE 5 , 6 View FIGURE 6 , 7B View FIGURE 7 )

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 View FIGURE 5 , F, H). Color. Body black ( Fig. 5A, B View FIGURE 5 ). 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 View FIGURE 6 ). 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 View FIGURE 5 ). Frons in profile slightly depressed apically ( Fig. 5E View FIGURE 5 : green line); supra-antennal carina in dorsal view broadly rounded, but slightly emarginate apically ( Fig. 5C View FIGURE 5 ), in profile strongly prominent anteriad above clypeus ( Fig. 5E View FIGURE 5 : arrow). Antennae extending beyond pronotum posterior lateral apices by apical two antennomeres ( Fig. 5A View FIGURE 5 ); 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 View FIGURE 5 : 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 View FIGURE 5 : black arrow); posterior margin without large emargination, weakly sinuate. Anterior lobe of prosternum slightly exceeding anterior angles of prothorax ( Fig. 5B View FIGURE 5 ), in profile weakly inclined (at 24 degrees against prosternal horizontal line, Fig. 5E View FIGURE 5 : red line). Prosternal spine in profile strongly inclined (at 23 degrees against prosternal horizontal line, Fig. 5G View FIGURE 5 : red line); ventral margin in profile without distinct subapical tooth and sinuate; lateral lobe in profile with ventral margin straight apically ( Fig. 5G View FIGURE 5 : yellow line), at ventral view with sides roundly expanded and anteriorly strongly prominent ( Fig. 5H View FIGURE 5 : arrows); apical margin at ventral view rounded, with weakly prominent apex ( Fig. 5H View FIGURE 5 ). Pronotosternal sutures not grooved, anteriorly opened and appearing double ( Fig. 5F View FIGURE 5 : white arrow). Scutellum 1.30 x as long as wide ( Fig. 5I View FIGURE 5 ), weakly widening posteriad, widest near posterior 2/5, weakly elevated medially ( Fig. 5G View FIGURE 5 : arrow), moderately inclined anterior-downwards; anterior margin almost transverse; posterior margin broadly rounded, but emarginate medially ( Fig. 5I View FIGURE 5 : arrow). Mesosternum with a median longitudinal carina posterior to mesosternal cavity; borders of mesosternal cavity sinuate followed by strongly declivous ( Fig. 5H View FIGURE 5 : 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 View FIGURE 5 ); ventrite V 0.57 x as long as wide. Sternite VIII with median notch rounded ( Fig. 6B View FIGURE 6 ). Tergite IX 1.22 x length of tergite X ( Fig. 6C View FIGURE 6 ). Tergite X 1.12 x as long as wide ( Fig. 6C View FIGURE 6 ). Sternite IX transverse apically ( Fig. 6D View FIGURE 6 ). Aedeagus ( Fig. 6E, F View FIGURE 6 ). 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 View FIGURE 7 ), 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.