Macrotomoderus truncatulus, 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 : 68-73

Macrotomoderus truncatulus sp. nov.

urn:lsid:zoobank.org:act:103D0B56-52BD-40E6-8373-8DBAF4775303

Figs 40–41

Differential diagnosis

This species readily differs from all Palaearctic congeners in the truncate head base and obtusely angulate (not rounded) temporal angles. The modifications of anterior margin of the pronotum are similar to those as in M. lapidarius sp. nov. (see description above), but specifically different in the less prominent and obtusely angulate lateral denticles of the anterior pronotal impression (the denticles stronger raised in dorsal aspect, either acute in M. lapidarius sp. nov.) and the less prominent anterior wall of the pronotal impression (the wall is higher in M. lapidarius sp. nov.). See also diagnosis of M. similis sp. nov. above.

Etymology

Named from the Latin ‘truncatulus’ (‘slightly truncate’) to point on truncate head base.

Type material

Holotype CHINA • ♂; “CHINA, Yunnan, Wuliangshan Mt. Range 2270 m, 12.vi.2011 Belousov, Kabak & Korolev leg. // 24°45′02″N 100°30′24″E ”; ZIN.

Description

MEASUREMENTS. Holotype, total body length 4.15 mm; head 0.85 mm long, across eyes 0.8 mm broad, pronotum 1 mm long, maximum width 0.75 mm, minimum width 0.4 mm, elytra 2.3 mm long, 1.6 mm combined wide.

Dorsum and venter uniformly pale brown. Mouthparts, antennae, palps and legs yellowish-brown. Head ovoid with moderately large, ovoid compound eyes, which are not or slightly protruding beyond head outline laterally. Tempora converging towards obtusely angulate temporal angles; head base truncate. Occiput somewhat declivous posterodorsally. Head dorsal punctures minute and inconspicuous. Head dorsal setae inconspicuous, sparse. Antennae extending towards base of pronotum. Antennomere three about 1.2× as long as antennomere two, antennomeres 8–10 transverse, of them 9–10 strongly transverse. Terminal antennomere shortly triangular with rounded apex, twice as long as penultimate antennomere. Terminal maxillary palpomere securiform. Pronotum shortly cylindrical with broad and medially shortly notched postmedian lateral constriction. Front margin of anterior lobe broadly rounded, in male shallowly and broadly impressed mesally opposite median part of head base; anterolateral margins of this impression are slightly raised in dorsal aspect, obtuse denticulate ( Fig. 40B–C ). Anterior edge of pronotum in front of anterior impression with gentle, low and short median wall that in male is provided with golden, long, in part curved, anteriad-pointing setae ( Fig. 40B–C ). Lateral angles of this wall on each side with a few long, apically curved, erect setae; both groups of lateral setae are meeting apically in a П-shaped arc over anterior wall ( Fig. 40B ). Pronotum dorsally without anterior rim. Anterior lobe slightly convex in lateral view ( Fig. 40C ). Lateral constriction slightly continues onto disc in lateral view, shallow ( Fig. 40C ). Lateral pronotal fovea moderately broad at lower external margin of pronotum, widens upwards towards pronotal disc in lateral view, external margins protruding into a pair of obtuse (in lateral view), widely separated denticles (in lateral view). Cavity in lateral wall of pronotum between lateral denticles elliptical. In dorsal view, lateral pronotal fovea moderately broad, anterior and posterior pair of denticles appear obtusely angulate, poorly visible from above, dorsally each with a bunch of short setae ( Fig. 40B ). Pronotal punctures minute on disc; lateral constriction dorsally with dense, irregularly shaped and variably sized punctures, some of which are large. A track of short median longitudinal carina present on lateral constriction area in dorsal view. Dorsal pronotal setae rather long, appressed, at least in part obscuring surface of posterior pronotal lobe. Scutellar shield small, apically rounded. Elytra dorsally elongate elliptical, slightly convex in lateral view, widened laterally around midlength, shoulders obsolete (apterous species). Elytral punctures moderately large, rather dense, becoming smaller and sparser towards apices. Elytral setae long and sparse, suberect. Male tergite and morphological sternite VII broadly rounded at posterior margin. Aedeagus as in Fig. 41 , large and robust, with delicate, moderately large needle-shaped and tube-enclosed gonopore armature. Constituting pieces attached closely to one another.

Sexual dimorphism

Female is unknown.

Ecology

Collected at 2270 m elevation.

Distribution

Known only from Wuliang Mountains in central part of Yunnan Province, SW China.

Figures

Fig. 40. Macrotomoderus truncatulus 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. 41. Macrotomoderus truncatulus sp. nov., holotype, ♂ (ZIN), aedeagus. A–B. General view, different positions. C. Gonopore armature, median portion of apicale. D. Ditto, basal portion of apicale and apical portion of basale. E. Median portion of apicale, different position. F. Apical portion. G. Ditto, different position. Not to scale.