Cyclosomus acutangulus Kavanaugh and Cueva-Dabkoski, 2023

Kavanaugh, David H., Cueva-Dabkoski, Mollie & Liang, Hongbin, 2023, Inventory of the Carabid Beetle Fauna of the Gaoligong Mountains, western Yunnan Province, China: Species of the Tribe Cyclosomini Laporte, 1934 (Coleoptera: Carabidae), with Descriptions of Two New Species., Proceedings of the California Academy of Sciences 67 (20), pp. 451-491 : 458-459

publication ID	https://doi.org/ 10.5281/zenodo.11067293
DOI	https://doi.org/10.5281/zenodo.12628239
persistent identifier	https://treatment.plazi.org/id/644DE316-FF88-FFB0-D25E-DAAEFB446304
treatment provided by	Felipe
scientific name	Cyclosomus acutangulus Kavanaugh and Cueva-Dabkoski
status

Treatment

Key for identification of adult cyclosomine species of the Gaoligong Shan region of China

1 Size larger, BL = 6.8 mm or more; pronotum ( Fig. 13A View FIGURE ) very broad, trapezoidal, almost as wide as elytra at humeral angles, distinctly widest at base; elytra broadly rounded apically, elytral color pattern as in Fig. 7A View FIGURE ; front tarsomeres 1 to 3 markedly expanded laterally ( Figs. 14A View FIGURE , 15A View FIGURE ) in both males and females................... Cyclosomus acutangulus Kavanaugh and Cueva-Dabkoski , sp. nov.

1’ Size smaller, BL = less than 6.0 mm; pronotum ( Figs. 13 View FIGURE B-D) narrower, widest at or anterior to middle; elytra slightly to distinctly and obliquely truncate apically, elytral color pattern varied; front tarsomeres 1 to 3 without distinct lateral expansions ( Figs. 14 View FIGURE B-F), broader in males than in females............................................................... Tetragonoderus spp. 2

2 (1’) Femora dark black or piceous; elytra dark without pale markings in basal half, with or without pale markings in apical half ( Figs. 9A View FIGURE , 11A View FIGURE )................................................. 3

2’ Femora pale tan; elytra with pale areas in both basal and apical halves ( Figs. 10A View FIGURE , 12A View FIGURE , 20 View FIGURE )........ 4

3 (2’) Size smaller, BL = 4.5 mm or less; elytra with distinct transverse subapical band of pale spots extended from interval 4 to interval 8 ( Fig. 11A View FIGURE ), faintly present also on interval 3 in some individuals, posterior discal setiferous puncture on interval 3 inserted more posteriad, at level of pale transverse subapical band; dorsal surfaces shiny, with distinct aeneous-greenish metallic reflection, of similar sheen throughout, elytral microsculpture comprised of more or less regularly transverse meshes, except their orientation slightly distorted in or near discal setal pore punctures........................................................... Tetragonoderus parviculus Kavanaugh and Cueva-Dabkoski , sp. nov.

3’ Size larger, BL = 4.9 mm or more; elytra ( Fig. 9A View FIGURE ) with only faint pale markings in region of subapical band, most evident on intervals 7 and 8, posterior discal setiferous puncture on interval 3 inserted distinctly anterior to level of pale subapical markings (i.e., closer to anterior discal setiferous pore); dorsal surfaces duller, with distinct bronze/copper metallic reflection, sericeous (silky) and mottled in posterior half, with elytral microsculpture comprised of a complex pattern of transverse, longitudinal, and oblique patches of elongate meshes, most distorted near discal and umbilicate setal pore punctures.................................................................. Tetragonoderus arcuatus Dejean

4 (3’) Elytral color pattern as in Fig. 10A View FIGURE , with dark areas more expansive; connection between medial portion of the basal dark band and humeral portion broader, at least one-quarter length of the humeral portion; middle band with portion between anterior and posterior dark edges distinctly darker (orange-brown) than remainder of pale elytral areas; pronotum dark, black or piceous, with distinct greenish or bronze metallic reflection, slightly narrowed basally (ratio PWM/PWB =1.13 to 1.20); male with middle tarsomeres 1 to 4 ( Fig. 16C View FIGURE ) distinctly wider than in female and with pads of adhesive setae ventrally ( Fig. 17C View FIGURE ); median lobe of male genitalia ( Figs. 19A,B View FIGURE ) with conspicuous large spines on the internal sac....................................................... Tetragonoderus elegans Andrewes

4’ Elytral color pattern as in Figs. 12A View FIGURE , 20 View FIGURE , with dark areas less expansive; connection between medial portion of the basal macula and humeral macula absent or very narrow, less than one-fifth the length of humeral macula; middle discal band with portion between anterior and posterior dark edges not or only very slightly darker than remainder of pale elytral areas; pronotum piceous or rufopiceous, with or without faint greenish metallic reflection, narrowed basally or not; male with middle mesotarsomeres ( Figs. 16E,F View FIGURE ) only slightly wider than in female and with only tarsomeres 1 to 3 with pads of adhesive setae ventrally (i.e., tarsomere 4 without adhesive setae ventrally) ( Figs. 17E,F View FIGURE ); median lobe of male genitalia ( Figs. 19 View FIGURE C-F) without spines on the internal sac........................................... 5

5 (4’) Pronotum ( Fig. 13E View FIGURE ) slightly shorter and wider (ratio PWM/PL = 1.52 to 1.70), widest near mid-length and posterior to insertion of midlateral seta, not or only very slightly narrowed basally (ratio PWB/PWA = 1.15 to 1.25), lateral margins slightly and evenly convex or straight or very slightly sinuate anterior to basal angles; elytra intervals flat and striae moderately impressed; median lobe of male genitalia ( Figs. 19C,D View FIGURE ) with apical lamella slightly shorter and broader...... Tetragonoderus punctatus (Wiedemann)

5’ Pronotum ( Fig. 13F View FIGURE ) slightly longer and narrower (ratio PWM/PL = 1.48 to 1.57), widest anterior to mid-length at or near insertion of midlateral seta, slightly to moderately narrowed basally (ratio PWB/PWA = 1.04 to 1.14), lateral margins slightly to moderately sinuate anterior to basal angles; elytra intervals slightly convex and striae deeply impressed; median lobe of male genitalia ( Figs. 19E,F View FIGURE ) with apical lamella slightly longer and narrower................... [ Tetragonoderus microthorax Jian & Tian ]