Macrotomoderus daxiangling, Telnov, 2022

Telnov, Dmitry, 2022, Revision of the Tomoderinae (Coleoptera: Anthicidae). Part III. New species and records of Macrotomoderus Pic, 1901 from China and a key to the Palaearctic species, European Journal of Taxonomy 797, pp. 1-100 : 23-26

Macrotomoderus daxiangling sp. nov.

urn:lsid:zoobank.org:act:E2523A73-13E9-405A-BEA2-A37E9DA709ED

Figs 12–13

Differential diagnosis

This taxon, that falls in a group of species with the denticles of the lateral pronotal constriction not exposed in dorsal view, is primarily recognizable among its congeners by the shape of the male aedeagus in the combination with the gently sculptured dorsal area of the pronotal constriction (the area is slightly, irregularly, longitudinally rugulose with finely punctured intervening spaces). Also see key to species below.

Etymology

Toponymic. This species named after the Daxiangling Mountains, a small montane range located at the western rim of the Sichuan Basin, where this species was first collected. Noun in apposition.

Type material

Holotype CHINA • ♂; “CHINA, Sichuan, Emeishan Cl. , ENE Longchizhen Village 2900 m, 4.v.2010 Belousov & Kabak leg. // 29°24′51″N 103°11′29″E ”; ZIN.

Description

MEASUREMENTS. Holotype, total body length 3.75 mm; head 0.75 mm long, across eyes 0.7 mm broad, pronotum 0.9 mm long, maximum width 0.7 mm, minimum width 0.3 mm, elytra 2.1 mm long, 1.7 mm combined wide.

Dorsum and venter uniformly brown. Mouthparts, antennae, palps and legs yellow. Head ovoid with small, ovoid compound eyes, which are slightly protruding beyond head outline laterally. Head rounded in broad arc posterior to eyes. Head dorsal punctures minute and inconspicuous. Head dorsal setae inconspicuous, sparse. Antennae comparatively short, extending slightly over lateral constriction of pronotum. Antennomere three about 1.1–1.2 × as long as antennomere two, antennomeres 8–10 transverse, of them 9–10 strongly transverse. Terminal antennomere short, asymmetrically triangular with rounded apex, about 1.2–1.25× as long as penultimate antennomere. Terminal maxillary palpomere slightly securiform. Pronotum with broad, medially not notched (in dorsal view) postmedian lateral constriction. Front margin of anterior lobe very broadly rounded dorsally, medially subtruncate, with narrow dorsal anterior rim ( Fig. 12B ). Anterior lobe slightly convex in lateral view ( Fig. 12C ). Lateral constriction slightly continues onto disc in lateral view, very shallow ( Fig. 12C ). Lateral pronotal fovea moderately broad at lower external margin of pronotum, widens upwards and deepens towards pronotal disc in lateral view, external margins protruding into small, strongly obtuse (in lateral view), moderately widely separated denticles (in lateral view). Cavity in lateral wall of pronotum between lateral denticles not observed. In dorsal view anterior and posterior pair of lateral constriction deeply notched, no denticles visible ( Fig. 12B ). Pronotal punctures minute on disc; lateral constriction dorsally with few irregular, glabrous, longitudinal rugules and small, irregularly shaped punctures between them. Dorsal pronotal setae inconspicuous, moderately long. Scutellar shield minute, triangular. Elytra dorsally elliptical, flattened in lateral view, widened laterally around midlength, lateral margins evenly broadly rounded, shoulders obsolete (apterous species). Elytral punctures much stronger and larger than those on dorsal forebody, becoming smaller and less deep in apical third of elytra. Elytral setae moderately long and sparse, suberect. Male tergite and morphological sternite VII broadly rounded at posterior margin. Aedeagus as in Fig. 13 , large and robust, with large, bubble-like basale and peculiar gonopore armature. Gonopore armature double in basale, consists of dense, irregularly shaped and positioned, small and very large constituting pieces. Apicale in basal half with two ‘garlands’ of dense, spineshaped, closed attached to one another gonopore armature. ‘Garlands’ fuse together in apical half of apicale, constituting pieces of armature becoming distinctly smaller and almost perfectly spine-shaped near apex of aedeagus.

Sexual dimorphism

Female is unknown.

Ecology

Collected at 2900 m elevation.

Distribution

Known only from Daxiangling Mountains in Sichuan Province, central China.

Figures

Fig. 12. Macrotomoderus daxiangling sp. nov., holotype, ♂ (ZIN). A. Habitus, dorsal view.B. Forebody, dorsal view. C. Ditto, lateral view. Scale bar: A = 1 mm; B–C = not to scale.

Fig. 13. Macrotomoderus daxiangling sp. nov., holotype, ♂ (ZIN), aedeagus. A–B. General view, different positions. C. Gonopore armature in apical portion of aedeagus. D. Ditto, median portion. E. Ditto, stronger magnification. F. Basale. G. Apical portion. Not to scale.