Pseudocneorhinus angustus, Ren, Li, Borovec, Roman & Zhang, Runzhi, 2019

Ren, Li, Borovec, Roman & Zhang, Runzhi, 2019, On the genus Pseudocneorhinus (Coleoptera, Curculionidae, Entiminae), with descriptions of five new species from China, ZooKeys 853, pp. 57-86 : 57

Pseudocneorhinus angustus sp. nov. Figs 1, 2, 31

Type locality.

Valley of Fubianhe river (China: Sichuan).

Material examined.

Holotype. CHINA - Sichuan Prov. ♂; valley of Fubianhe river; 2 Aug. 1893; Potanin leg.; ZIN. Paratype. CHINA - Sichuan Prov. 1 ♂; same data as for holotype; 5 Aug. 1893; ZIN.

Description.

Body length: Holotype 3.41 mm, paratype 3.50 mm.

Body (Figs 1, 2) blackish, basal half of antennal scape, funicle and tarsi reddish brown, mucro and claws reddish. Appressed scales covering antennae, head, pronotum, elytra and legs, except antennal club; scales on elytra small, irregularly angular, with indistinct depression in the middle; 4-6 scales across interval width, somewhat sparse, narrowly separate; scales light brownish with V-shaped transverse stripe from greyish scales on elytral declivity. Raised elytral setae conspicuous, erect, long and wide, spatulate, positioned in single dense row only on odd intervals, with short longitudinal clumps of intervals 3 and 5 on declivity; setae white greyish and blackish, alternating irregularly. Semierect setae on pronotum, head and rostrum half as long and wide as elytral ones, irregularly scattered. Antennae and legs except for basal half of scape with semierect moderately long setae, prominent from outline.

Rostrum (Figs 1, 2) long and slender, 1.09-1.11 × as long as wide, abruptly widened from base to basal one-fourth, then weakly tapered anteriad, with straight sides. Epifrons somewhat tapered from base to apex, with straight sides, longitudinally depressed along the whole length. Epistome short and wide, apices distinctly wider than anterior part of epifrons, separated from frons by indistinct slender carina. Frons squamose with three pairs of stout, yellowish setae. Antennal scrobe in dorsal view almost invisible; in lateral view curved, short, directed towards eyes. Rostrum in lateral view strongly convex, indistinctly separated from head by shallow transverse depression. Eyes hardly prominent from outline of head.

Antennae slender with robust scape. Scape as long as funicle, weakly curved, regularly but distinctly enlarged apicad in apical half, at apex 1.4-1.6 × as wide as club. Funicle segment 1 as long as and slightly wider than segment 2, both conical; segment 1 twice as long as wide; segment 2 2.3-2.4 × as long as wide; segments 3 and 4 1.1-1.2 × as long as wide; segments 5 and 6 isodiametric; segment 7 1.1-1.2 × as wide as long; club 1.7-1.8 × as long as wide.

Pronotum (Figs 1, 2) 1.26-1.27 × as wide as long, with weakly rounded sides, widest at midlength, more tapered anteriad than posteriad. Disc regularly convex. Anterior border in lateral view sinuose, ocular lobes well developed. Base weakly convex.

Elytra (Figs 1, 2) slender, elongate oval, 1.25-1.29 × as long as wide, widest behind midlength, not wider at shoulders. Striae distinct, weakly curved on elytral disc. Even intervals wider and more elevated than odd intervals, mainly in basal part and on elytral declivity. Base straight laterally, sinuate only in middle between third intervals. Elytra in lateral view moderately convex.

Protibiae rounded at apex, with fringe of very short yellowish setae, mucronate. Inner side of all tibiae without teeth. Metatibial corbels squamose. Tarsi robust; segment 2 1.2-1.3 × as wide as long; segment 3 1.3-1.4 × as wide as long and 1.3-1.4 × as wide as segment 2; onychium 1.1-1.2 × as long as segment 3. Claws fused in basal half.

Penis (Fig. 31) short with weakly rounded sides; apex distinctly tapered, subtriangular with concave sides. Penis in lateral view short and wide, obtuse with slender elongated apex in ventral side.

Female genitalia unknown.

Biology.

Unknown.

Distribution.

China: Sichuan (Fig. 52).

Etymology.

The name is a Latin adjective meaning narrow and used to refer to the unusually slender elytra.

Differential diagnosis.

Pseudocneorhinus angustus is similar to P. hirsutus ( Formánek, 1916) and P. squamosus Marshall, 1934 in having distinctly enlarged antennal scapes, squamose frons, only medially (between third intervals) sinuate elytral base and small body size. It is possible to distinguish it from both these species by raised setae confined to odd intervals ( P. hirsutus and P. squamosus have setae on all intervals), rostrum 1.1 × longer than wide ( P. hirsutus and P. squamosus have rostrum isodiametric), epifrons tapered apicad with straight sides ( P. hirsutus and P. squamosus have epifrons parallel-sided, at base weakly concave), epistome with apices distinctly wider than anterior part of epifrons ( P. hirsutus and P. squamosus have epistome with apices distinctly narrower than anterior part of epifrons) and elytra slender, interval 1 at declivity much wider than on the disc ( P. hirsutus and P. squamosus have elytra wider with interval 1 equally wide along the whole length). Other similar species with raised setae only on odd intervals are P. alternans Marshall, 1934, P. setosicallus sp. nov. and P. subcallosus (Voss, 1956). P. angustus can be distinguished from all these three species by smaller body size, long and wide spatulate raised elytral setae and apically distinctly enlarged scapes (apex wider than club). Pseudocneorhinus angustus is most similar to P. setosicallus because of long erect setae on the elytra; they can be distinguished by the characters specified in the key below.