Microhoria taguan, Telnov, 2024

Telnov, Dmitry, 2024, New species and records of Anthicidae Latreille, 1819 (Coleoptera) from Taiwan with a key to Asian Nitorus Telnov, 2007 species with gibbose pronotum, Zootaxa 5507 (2), pp. 285-312 : 303-306

Microhoria taguan sp. nov. ( Figures 14–16 )

urn:lsid:zoobank.org:act:B856238D-6993-4DAB-909D-CF5F2C1D343A

This species belongs to the longiceps species-group as of Kejval & Chandler (2020).

Type material designated. Holotype ♂, BMNH: TAIWAN, Nantou County N24°02.530’; E121°12.555’ beating etc. 1920m 6.viii.2008 M.V.L. Barclay, H.Mendel & R. Ewers BMNH (E) 2008-85 [printed].

Paratypes 2♂ & 4♀ BMNH: TAIWAN, Kaohsiung County Nanheng Sanshan , 2574m trail above road, 12.viii.2008 N23°15.970’ E120°56.373’ H.Mendel & MVL Barclay BMNH (E) 2008-85 [printed] .

Derivatio nominis. Toponymic. Named after Taguan Mountain in central Taiwan in the area where the type series was sampled. Noun in apposition.

Measurements, holotype male, total body length excluding partially exposed terminalia 3 mm; head length 0.6 mm, head width across compound eyes 0.55 mm, pronotal length 0.6 mm, maximum pronotal width 0.45 mm, minimum pronotal width in constriction area 0.35 mm, elytral length 1.8 mm, combined maximum elytral width across midlength 1 mm. Male paratypes 2.9 mm, female paratypes 2.8–3.2 mm long.

Description. Holotype male. Dorsal and ventral head brown, paler yellowish around antennal insertions and on clypeus. Pronotum yellowish brown. Elytra brown, each elytron with poorly defined yellowish humeral (smaller) and postmedian (larger) spot; spots distinctly separated, not confluent. Maxillary palpus, antenna and legs pale yellow-rufous. Ventral pterothorax and abdominal ventrites brown. Head elongate elliptical, hardly 1.1× as long as wide, slightly convex in dorsal aspect, glossy. Labrum subtruncate at anterior margin. Frontoclypeal suture present, slightly arched (shallowly concave anteriorly). Compound eye moderate, about 0.7× as long as converging tempus, strongly protruding from lateral outline of head. Head base rounded, posterior temporal angles obsolete. Head dorsal punctures moderately large, shallow, sparse. Intervening spaces smooth and glossy, as wide as to twice as wide as punctures. Dorsal cranial setae yellowish, sparse, and inconspicuous. Antenna extending slightly beyond elytral base when directed posteriad, hardly thickened in apical half. Antennomeres 7–10 somewhat widened and shortened, more regularly trapezoid in dorsal view, slightly widened distally. Penultimate antennomere about 1.1–1.2× as long as wide. Terminal antennomere elongate, bluntly pointed, about 2.2–2.3× as long as penultimate antennomere, about the combined length of antennomeres 9–10. Penultimate maxillary palpomere lobate at mesal margin. Terminal maxillary palpomere securiform. Cranial ‘neck’ less than one third head width across compound eyes, densely finely punctured, moderately glossy. Pronotum longer than wide, distinctly narrower than head across eyes, subtruncate at anterior margin. Pronotal disc moderately glossy, anterior lobe slightly convex in dorsal aspect. Lateral margins broadly rounded in anterior half, moderately constricted postmedium. Anterior pronotal rim distinct dorsally, laterally and ventrally. Antebasal sulcus wide, well-developed dorsally and laterally. Pronotal punctures on anterior portion of pronotal disc larger than those on head, minute and sparse on lateral sides of anterior lobe, large and dense on basal half of disc, in particular, in constriction area. Large punctures are circular or elliptical, puncture background microreticulate or corrugate. Intervening spaces glossy, about as wide as punctures on anterior half of pronotal disc, narrower than those on rest of pronotal dorsum. Pronotal setae as those on head, somewhat longer, not fully appressed. Scutellar shield nearly triangular, apically rounded, glossy. Elytra elongate, about 1.8× as long as wide, widest at midlength, dorsally flattened. Postbasal transverse impression very feeble, nearly obsolete. Humerus broadly rounded. Apical sutural angle rounded.Apex of elytron modified, with a short, obtuse denticle at opening of a gland channel. Elytral surface glossy and smooth, punctures smaller than those on pronotal constriction, but distinct and dense. Intervening spaces smooth and glossy, generally as wide as punctures. Elytral setae yellowish, long and dense, suberect, directed posteriad. Metathoracic wing fully developed (functional). Legs without modifications, moderately densely setose. Tibial terminal spurs paired, inconspicuous. Basal metatarsomere longer than combined length of remaining metatarsomeres. Tergite VII broadly rounded at posterior margin ( Fig. 15A ). Morphological sternite VII broadly rounded at posterior margin ( Fig. 15B ). Morphological sternite VIII somewhat bow tie-shaped ( Fig. 15C ), sternite IX Y-shaped, arms moderately long ( Fig. 15D ). Aedeagus ( Fig. 15E–G ) elongate; tegmen each side with acute, sabre-like spine; endophallic armature of irregular shape.

Sexual dimorphism. Female ( Figs 14C–D , 16 ) slightly stouter, elytra stronger widened in median portion and comparatively stronger convex in dorsal aspect. Elytral sutural angle produced into a moderately long, acutely angulate process which is slightly curved ventrally at apex ( Fig. 14C ). Tergite VII strongly modified, posterior margin with subcircular, short, irregularly serrate median prong; posterior margin strongly deflected dorsoanteriad forming irregularly shaped, medially broadly emarginate and laterally irregularly serrate ‘pocket’ ( Fig. 16A–B ). Morphological sternite VII broad, deeply U-shapely emarginate medially at posterior margin ( Fig. 16C ). Morphological sternite IX rod-like ( Fig. 16D ).

Intraspecific variability. Head or whole dorsal forebody darker brown to black-brown in some paratypes. In one paratype anterior pale elytral spot not interrupted on suture, occupying whole basal fifth of elytra. Posterior pale paired spot extends to cover most of apical half of elytra except dark elytral apex but also in that case posterior spots are separated by dark sutural area. Dorsal pronotal punctures on constriction area vary strongly in shape and size. Total body length varies from 2.8 to 3.2 mm.

Differential diagnosis. Microhoria taguan sp. nov. is externally similar to Taiwanese M. lingua sp. nov. (described herein) and several other similarly-coloured Himalayan and eastern-Palaearctic congeners but is specifically different in the shape of the male aedeagus and the female tergite and morphological sternite VII.

Ecology. Occurs at about 1920–2574 m in forested area. The holotype collected by beating forest vegetation, a typical microstation of many Microhoria Chevrolat, 1877 species (see Telnov 2022).

Distribution. So far known from mountainous central part of Taiwan, Kaohsiung County.

Figures

FIGURE 14. Microhoria taguan sp. nov. A—Holotype ♂, habitus, dorsal view; B—ditto, forebody, dorsal view; C—Paratype ♀, habitus, dorsal view; D—ditto, forebody, dorsal view [not to scale].

FIGURE 15. Microhoria taguan sp. nov. holotype ♂. A—Tergite VII, dorsal view; B—Morphological sternite VII, ventral view; C—Morphological sternite VIII, dorsal view; D—Morphological sternite IX; E—Aedeagus; F—ditto, apex, magnified; G—ditto, median portion, magnified [not to scale].

FIGURE 16. Microhoria taguan sp. nov., paratype ♀. A—Tergite VII, dorsal view; B—ditto, median portion of posterior margin, magnified, dorsal view; C—Morphological sternite VII, ventral view; D—Morphological sternite IX [not to scale].