Macrotomoderus turpiculus, Telnov, 2024

Telnov, Dmitry, 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, pp. 231-250 : 231-250

Macrotomoderus turpiculus sp. nov.

Figs 5 , 6

Type material designated.

Holotype • ♂ IBC: “ CH, S Sichuan, S of Xichang, E slope of Mt.´4282´(NE of Dechang) 3200– 2800 m, 6. 05. 2001 Belousov & Korolev leg. ” [printed] // “ Macrotomoderus sp. ? n. aff. monstrificabilis [handwritten] A. Kovalev det. 20 [printed] 19 ” [handwritten] [label with black frame]. The holotype will be donated to a local public institution (I. Belousov, pers. comm. viii. 2021) . Paratype • 1 ♂ DTC: same labels as holotype .

Measurements.

Holotype, total body length 4.1 mm; head 0.8 mm long, across eyes 0.8 mm wide, pronotum 1.2 mm long, maximum width 1 mm, minimum width 0.25 mm, elytra 2.2 mm long, 1.5 mm combined wide. Paratype ♂ 4 mm long.

Description.

Holotype, male. Dorsum and venter brown, posterior lobe of pronotum slightly paler. Mouthparts, antennae, palps, and legs brownish testaceous. Head subtriangular, moderately glossy dorsally and ventrally, with moderate, slightly ovoid compound eyes which are slightly protruding beyond lateral outline of head. Tempus short, constricted towards head base, temporal angle rounded. Head base truncate, declivous. Head dorsal punctures minute and inconspicuous, flat. Intervening spaces much wider than punctures. Head dorsal setae yellowish, short, moderately dense. Head base medially with somewhat longer, apically curled golden setae. Antenna exceeds slightly beyond base of elytra when directed posteriad. Antennomere 3 ~ 2 × as long as antennomere 2, asymmetrical, distal edge obliquely emarginate to accommodate shortened and only slightly longer than wide antennomere 4, antenna appears somewhat bent at area of antennomeres 3–5 (Fig. 5 A, B, F ). Antennomeres 8–10 transverse, of which antennomere 10 strongly so. Terminal antennomere strongly asymmetrically triangular with rounded apex, ~ 1.8–1.9 × as long as penultimate antennomere. Terminal maxillary palpomere securiform. Pronotum stout, moderately glossy dorsally and laterally, much wider than head across compound eyes, with moderately broad, medially strongly notched (in dorsal view) postmedian lateral constriction. Anterior lobe much wider than posterior, its front margin medially subtruncate, without anterior rim, with moderate mesal impression and transverse median ridge covered with dense golden setae which are directed antero-dorsally (Fig. 5 C – E ). Pronotum flattened anteroventrally each side of subtruncate median part of its anterior margin (Fig. 5 D, E ). Anterior lobe convex in lateral view (Fig. 5 B ). Lateral constriction barely continues onto disc in lateral view (Fig. 5 B ). Lateral pronotal fovea broad at lower (lateroventral) extent of laterally strongly declivous pronotal disc, not or barely widens upwards towards pronotal disc, lateral edges of fovea carinate, narrowly separated, nearly glabrous (all in lateral view), in dorsal view denticle-like. In lateral view anterior and posterior edge of pronotal fovea covered with a bristle of moderately long whitish setae. In dorsal view, lateral pronotal fovea wide, anterior and posterior denticle clearly visible, in part setose (Fig. 5 A, C ). There is an inconspicuous trace of short dorsal median longitudinal carina in lateral constriction area. Pronotal punctures on disc small and sparse, intervening spaces 5–8 × as wide as diameter of punctures; lateral constriction dorsally with irregularly ovoid and variably dense, deep punctures. Intervening spaces among punctures in laterally constricted area vary from much narrower than to twice as wide as punctures. Dorsal pronotal setae short and dense, much longer and denser at lateral pronotal fovea, in part concealing its structure in dorsal view. Few longer erect tactile setae on lateral sides of anterior lobe. Scutellar shield minute, apically rounded, moderately glossy. Elytra moderately glossy, dorsally elongate elliptical, moderately convex in lateral view, widened laterally around midlength, lateral margins broadly rounded, humerus broadly rounded. Metathoracic wings fully developed (functional). Elytral punctures stronger and larger than those on dorsal forebody, nearly as large as those on lateral constriction area, more or less regularly circular. Punctures becoming more flat and somewhat sparser on apical third of elytra. Intervening spaces ~ 2.5–4 × as wide as diameter of punctures. Elytral setae long and moderately dense, suberect, yellowish. Male tergite and sternite VII broadly rounded at posterior margin. Aedeagus as in Fig. 6 , elongate and narrow, narrows and acutely angulate apically. Endophallic armature of numerous basally multifurcate spines (Fig. 6 A – E ).

Sexual dimorphism. Female is unknown.

Differential diagnosis.

This species falls into a group of species from mainland China with strongly widened, apically subtruncate anterior margin of pronotum, long heavy antennae, and slender, dagger-shaped aedeagus: M. imitator Telnov, 2022 , M. monstratus Telnov, 2018 , and M. monstrificabilis Telnov, 2018 (all from Yunnan). Macrotomoderus turpiculus sp. nov. is peculiar due to the absence of the large elongate median projection on head base (large projection present in M. monstrificabilis , only small projection in M. turpiculus sp. nov.; cf. Fig. 5 A, C, E ), the truncate and declivous head base (the head base broadly rounded in the similar species, not declivous), the differently modified anterior pronotal margin (see the description) especially the anteroventrally flattened pronotum, the asymmetrical antennomere 3 and the shortened antennomere 4 (both not modified in M. monstratus ), the wide head (the head is narrower than the pronotum in M. imitator ), and the peculiar endophallic armature not like in other congeners.

Ecology.

Collected between 2800–3200 m a. s. l.

Distribution.

Known only from southern part of Sichuan Province, southwestern China.

Etymology.

From Latin turpiculus – misshaped, ugly, referring to the unusual body shape of this species.

Figures

Figure 5. Macrotomoderus turpiculus sp. nov. ♂ A holotype, habitus, dorsal view B ditto, lateral view C ditto, dorsal forebody D paratype, forebody, anterodorsal view E ditto, latero-dorsal view F holotype, right antenna. Scale bars: 1 mm.

Figure 6. Macrotomoderus turpiculus sp. nov. holotype ♂, aedeagus A ventral view B lateral view C median portion, lateral view D basal portion, lateral view E basal portion, endophallic armature, ventral view F apical portion [not to scale].