Blinstein ant-like beetle (Macrotomoderus blinsteini), hairy ant-like beetle (M. hirsutus) and ugly ant-like beetle (M. turpiculus) from China

NEWS - Blinstein ant-like beetle (Macrotomoderus blinsteini Telnov sp. nov.), hairy ant-like beetle (Macrotomoderus hirsutus Telnov sp. nov.) and ugly ant-like beetle (Macrotomoderus turpiculus Telnov sp. nov.) from the Chinese plateau are expanding their geographical distribution.

Macrotomoderus Pic 1901 is the second species-bearing genera among the six genera Tomoderinae Bonadona 1961. Its geographical distribution is very wide and extends from the Indo-Australian Archipelago (Greater Sunda Islands southward including Java), mainland Southeast Asia, the Philippine Islands to the Indian Subcontinent, China, Japan and the Taiwan archipelago.

Currently 146 species are attributed to Macrotomoderus of which 96 are Oriental and 50 are Palaearctic. Additional species are described in this paper. Now Dmitry Telnov from Daugavpils University in Latvia reports the description of 3 new Macrotomoderus species from mainland China.

Macrotomoderus blinsteini was found at an elevation of 1700-1750 m in the Daba Mountains of southern Shaanxi Province along the border with Sichuan, central China. The species is named after Semen Blinstein, a coleopterist who had a valuable collection of beetles from southern Ukraine and the author of several species of Anthicidae from the region.

Holotype, total body length 3.9 mm; head including exposed part of cranial ‘neck’ 0.8 mm long, across eyes 0.8 mm wide, pronotum 1 mm long, maximum width 0.8 mm, minimum width 0.3 mm, elytra 2.1 mm long, combined width 1.4 mm. Paratype ♀ 4 mm long.

Female with tergites and sternite VII broadly rounded at the posterior margin, pronotum relatively slender and elytra somewhat more strongly tapering towards the apex than in males.

This species belongs to a group of species from mainland China including, for example, Macrotomoderus hartmanni Telnov 2022 and Macrotomoderus korolevi Telnov 2022 (both from Yunnan) with dense and rough lateral constrictions of the pronotum but regular and sparsely to moderately densely spotted dorsally, lacking longitudinal carinae, sulci, or longitudinal pores.

The aedeagus is shaped differently in M. blinsteini, the endophallic skeleton is smaller, thinner, and tack-like, and the elytra are relatively coarser and deeper.

Macrotomoderus hirsutus was collected at an elevation of 1900 m in the Daba Mountains in western Hubei Province, central China. The specific epithet is derived from the Latin hirsutus, shaggy, coarse, referring to the fine hairs at the base of the head of this species.

This species is easily recognized by the presence of a dense clump of setae at the base of the male's head combined with the spike-like endophallic skeleton of the aedeagus. The aedeagus is somewhat similar in shape to Macrotomoderus dali Telnov 2022 (Yunnan, China), Macrotomoderus muli Telnov 2022 (Sichuan, China), and Macrotomoderus wudu Telnov 2022 (Gansu, China), but all three have completely different endophallic skeletons.

The more or less densely arranged cephalic bases are present in Macrotomoderus conus Telnov 2018, Macrotomoderus gracilis Telnov 2018, Macrotomoderus microscopicus Telnov 2018, Macrotomoderus monstrificabilis Telnov 2018, Macrotomoderus perforatus Telnov 2018, and Macrotomoderus schuelkei Telnov 2018 (all from Yunnan, China), but other morphological features and the endophallic skeleton are very different.

Macrotomoderus turpiculus was collected at an elevation of 2800-3200 m and is known only from the southern part of Sichuan Province, southwest China. The epithet is derived from the Latin turpiculus, irregular, ugly, referring to the unusual body shape of this species.

This species belongs to a group of species from mainland China with a greatly widened and truncated anterior edge of the pronotum, long and heavy antennae, and slender dagger-shaped aedeagus: Macrotomoderus imitator Telnov 2022, Macrotomoderus monstratus Telnov 2018, and Macrotomoderus monstrificabilis Telnov 2018 (all from Yunnan).

M. turpiculus is peculiar in the absence of a large elongate median projection on the head base (a large projection is present in M. monstrificabilis, only a small projection in M. turpiculus), a truncated and descending head base (the head base is broadly rounded in the same species, not descending), a differently modified anterior pronotal margin, especially an anteroventrally flattened pronotum, asymmetric antenomeres 3 and shortened antenomeres 4 (both unmodified in M. monstratus), a broad head (the head is narrower than the pronotum in M. imitator), and a peculiar endophallic skeleton unlike that of other relatives.

Original research

Telnov D (2024). Revision of the Tomoderinae (Coleoptera, Anthicidae). Part V. Three new Macrotomoderus Pic, 1901 from continental China and an updated key to the Palaearctic species. ZooKeys 1218: 231-250, DOI:10.3897/zookeys.1218.134413

Dlium theDlium