On the genus Pseudocneorhinus (Coleoptera, Curculionidae, Entiminae), with descriptions of five new species from China

Abstract Species of the genus Pseudocneorhinus occurring in or near China are reviewed, with description of five new species, Pseudocneorhinusangustussp. nov., P.glabersp. nov., P.hlavacisp. nov., P.obliquehumeralissp. nov., and P.setosicallussp. nov. from the provinces of Beijing, Gansu, Shaanxi, Sichuan, and Zhejiang. They are illustrated and compared with similar species, and a key is provided to all presently known species of the genus. Lectotypes of the following species are designated: Callirhopalussubcallosus Voss, 1956 [current name Pseudocneorhinussubcallosus (Voss, 1956)] and P.squamosus Marshall, 1934. Pseudocneorhinussquameus Morimoto, 2015 is confirmed for the fauna of China.

Together with the species newly described herein, the genus increases to 19 species known from the same area, with Pseudocneorhinus bifasciatus Roelofs, 1880 having been introduced into the USA (Wheeler and Boyd 2005). The latter is comparatively well studied, with known biology, larva, and pupa (for example Allen 1959, Zepp 1978. Males are known only in nine species and the others are assumed to be parthenogenetic. Marshall (1934) and Voss (1956) studied regional collections from China, Han et al. (2000) and  from South Korea and Morimoto et al. (2015) from Japan.
The genus was recently redescribed by Borovec (2009). Pseudocneorhinus is related to genera Rhinodontus Faust, 1890 and Rhinodontodes Voss, 1967 sharing with them the ocular lobe in the lateral part of anterior pronotal margin, but it differs from both by the ocular lobe without setae, the rostrum lacking a lengthened epistome in females, the antennal scape exceeding the posterior border of eye and the apex of the protibia not enlarged laterally. The present study reviews the extensive material held by the Institute of Zoology at the Chinese Academy of Sciences Beijing, the Natural History Museum London, and the Zoological Institute Saint Petersburg, but also from some private collections. Previously published keys to the species of Pseudocneorhinus included those to the Korean  and Japanese faunas (Morimoto et al. 2015), but no key to all the species has been published since Marshall's (1934) review of the genus, in which the number of recognised species is half that recognised in the current paper; a full key is given below. In addition, illustrations of diagnostically important internal structures are provided.

Materials and methods
Body length was measured in profile from the anterior margin of the eyes to the apex of the elytra, excluding the rostrum. All other measurements were taken in dorsal view: rostral length between anterior margins of eyes and anterior margin of epistome, rostral width as maximum width, pronotal and elytral length along midline, and their widths as maximum extension across. Dissected female genitalia were embedded in Solakryl BMX. Dried male genitalia were glued on the same mounting card as the insect. The terminology for rostrum and terminalia follows Oberprieler et al. (2014).
Photos of adults were taken with a Canon EOS 7D digital camera with an MP-E 65 mm macro lens and combined using CombineZP software. All habitus photos were edited with Adobe Photoshop CS3. Line drawings were made using a camera Lucida mounted on a Rathenow microscope. Maps were prepared with Simplemappr (Shorthouse 2010 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  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.  [3][4][5][6] blackish, mucro and fringe of setae on protibia yellowish to reddish, claws brownish. Appressed scales covering antennae, head, pronotum, elytra and legs, except antennal club; scales on dorsal part of body small, irregularly angular, depressed in the middle, 8-9 scales across elytral interval width, narrow separate; scales light greyish with feeble pearly sheen, on elytra with slender transverse dark brownish stripe at anterior third and wider dark brownish stripe at apical third. Semiappressed elytral setae inconspicuous, strongly inclined, piliform to bristle-shaped, about as long as half of width of elytral interval, visible only in apical part or at base of elytra. Pronotum and head capsule and rostrum with identical semiappressed setae, these sparse and irregularly scattered, on pronotum directed transversely. Antennae and legs except for basal half of scape with semierect moderately long setae, prominent from outline.

Pseudocneorhinus glaber
Rostrum  in males longer and more slender than in females, in males 1.17-1.20 × as long as wide, in females 1.04-1.07 × as long as wide, regularly enlarged from base to midlength, then tapered anteriad with regularly rounded sides. Epifrons tapering from base to midlength and widened again with slightly rounded sides at basal and apical half, at apex narrower than at base, longitudinally widely and shallowly depressed. Epistome V-shaped, long, conspicuous, separated by slender carina from frons, in females at apex narrower than epifrons at apex, in males lengthened and curved along anterior border of rostrum, wider than epifrons at apex. Frons as a very narrow glabrous strip along epistome, bearing four pairs of stout and long apical setae, obliquely directed anteriad. Scrobe in doral view invisible; in lateral view narrow, subparallel-sided, long, weakly curved, directed towards middle of eyes. Rostrum in lateral view somewhat convex, in males longer and more slender than in females, separated from head by shallow transverse depression. Eyes hardly prominent from outline of head.
Elytra (Figs 3-6) 1.21-1.31 × as long as wide, ovoid, widest at apical third; shoulders absent, elytra at base hardly wider than base of pronotum, behind base with straight to slightly concave sides. Striae wide and distinct, punctate, punctures wide and completely hidden by appressed scales; intervals weakly convex, odd intervals slightly more so than even ones, equally wide, weakly wider than striae. Elytra in lateral view distinctly convex.
Penis (Fig. 32) short and wide, in ventral view slightly and regularly enlarged apicad, with straight sides, apex triangular with small triangular ends on sides; in lateral view almost straight, distinctly enlarged apicad, apex slender, elongate, dorsal border lengthened, lobe-like.
Differential diagnosis. Pseudocneorhinus glaber has inconspicuous elytral vestiture consisting of short, piliform setae that are semi-appressed and barely visible at apex and base in lateral view; all other species have elytra with conspicuous, moderate to very long setae of various widths and shapes, which are always more or less erect and well visible even in dorsal view. Pseudocneorhinus glaber resembles also species of the genus Rhinodontodes in having a long rostrum and medially constricted epifrons, but the epistome does not exceed the outline of the rostrum and the protibiae are straight. Body (Figs 7,8) blackish, only antennal club and basal part of first tarsal segment, mucro, fringe of setae at apex of protibia, and claws reddish. Appressed scales on body dense, hiding integument, oval, weakly imbricate, finely longitudinally striate, 5-6 scales across interval width; scales dark brownish with small light brownish spots irregularly scattered on elytra. Raised elytral setae semierect, slender, lanceolate, somewhat shorter than width of one elytral interval, with single sparse, regular row on each interval, setae greyish and blackish, alternating irregularly. Semierect setae on pronotum somewhat shorter than elytral ones, sparse, irregularly scattered. Semiappressed setae on head and rostrum half as long as pronotal setae. Antennae and legs except of basal half of scape with semierect moderately long setae, prominent in outline.
Rostrum (Figs 7, 8) long, 1.09-1.13 × as long as wide, regularly distinctly enlarged from base to antennal insertion, then rounded around apex, without abrupt widening at base. Epifrons tapered from base to midlength and widened again, at apex as wide as at base, longitudinally depressed, with somewhat swollen borders. Epistome V-shaped, long, conspicuous, separated by slender carina from frons, at apex as wide as epifrons in narrowest part. Frons glabrous, V-shaped, as a strip along epistome, bearing five pairs of stout, long apical setae, obliquely directed anteriad. Scrobe in dorsal view visible only in apical part as slender furrow; in lateral view narrow, short, curved, directed towards eye. Rostrum in lateral view somewhat convex, long and slender, separated from head by shallow transverse depression. Eyes weakly prominent from outline of head.
Antennae slender. Scape as long as funicle, straight, weakly and regularly enlarged to apex, at apex only slightly wider than club. Funicle segment 1 as long as and only slightly wider than segment 2, both conical; segment 1 1.7-1.8 × as long as wide; segment 2 1.9-2.0 × as long as wide; segment 3 1.2 × as long as wide; segment 4 1.1 × as long as wide; segments 5 and 6 isodiametric; segment 7 1.1 × as wide as long; club 1.6-1.7 × as long as wide.
Protibiae rounded at apex, with fringe of short and fine reddish setae, mucronate, on inner margin with 4-5 black, very small and indistinct teeth. Metatibiae with 1-3 black, very small and indistinct teeth in apical half; metatibial corbels squamose. Tarsi robust, segment 2 1.1-1.2 × as wide as long; segment 3 1.4-1.5 × as wide as long and 1.5-1.6 × as wide as segment 2; onychium equally long to 1.1 × as long as segment 3. Claws fused in basal half.
Male genitalia unknown. Female genitalia. Sternite VIII umbrella-shaped with short apodeme. Gonocoxites flat, weakly sclerotised with short apical styli, armed with setae. Spermatheca ( Fig. 38) with cornu long and regularly curved; ramus short twice as wide as long; nodulus short as ramus, half as wide as ramus, returned.
Biology. The specimens were sifted from forest litter. Distribution. China: Beijing (Fig. 52). Etymology. The newly described species is dedicated to the collector, our friend Peter Hlaváč (Prague, Czech Republic), well-known specialist of Staphylinidae (Pselaphinae, Scydmaeninae) and also Curculionidae.
Differential diagnosis. Pseudocneorhinus hlavaci is most similar to P. sellatus Marshall, 1934 in terms of size, overall shape, regular intervals, and dorsal contour of rostrum (i.e., evenly enlarged apically, base not abruptly widened). It is easily distinguishable from it by elytral setae conspicuous and semierect, rostrum slightly longer than wide with straight sides in basal half and epifrons without longitudinal carina. Description. Body length: holotype 5.31 mm, paratype 5.44 mm. Body (Figs 9, 10) blackish, only very short basal part of scape, club, mucro, and claws brownish and fringe of short setae at apex of protibiae yellowish. Appressed scales on body except pronotum, head capsule, rostrum and club imbricate, oval, small, finely longitudinally striate; 6-7 scales across interval width. Pronotum, head capsule and rostrum with appressed scales assembling on margins, irregularly tricuspid, narrowly separate. Club finely setose. Scales light brownish, elytra with narrow, transverse dark brownish stripe V-shaped at anterior third and straight at declivity. Elytra with narrow, subspatulate, longitudinally finely striate setae, appressed on disc, semiappressed on declivity, forming regular dense row on each odd interval, and very sparse, hardly visible row on even intervals, about as long as half width of one interval, light grey brownish, on even intervals dark brownish. Pronotum, head capsule and rostrum with identical appressed setae, on pronotum orientated transversely, on rostrum longitudinally, sparsely irregularly scattered. Scape and femora with moderately long semierect setae; funicle, tibiae. and tarsi with identical semierect setae, prominent from outline.

Pseudocneorhinus obliquehumeralis
Rostrum (Figs 9, 10) short and wide, 1.02-1.04 × as wide as long, narrowest at base, regularly moderately enlarged apicad with almost straight sides. Epifrons in basal almost two thirds tapered anteriad, in anterior third slightly enlarged again, in both parts with weakly convex sides, longitudinally shallowly depressed. Epistome V-shaped, moderately sized, separated by slender carina from frons, at apex distinctly narrower than apical part of epifrons. Frons as very slender glabrous strip along epistome, bearing 3-4 pairs of long, stout setae, obliquely directed anteriorly. Scrobe in dorsal view visible as very slender furrow in apical part; in lateral view short, weakly curved, narrow, directed towards middle of eyes. Rostrum in lateral view weakly convex, separated from head by shallow transverse depression. Eyes weakly prominent from outline of head.
Elytra (Figs 9, 10) 1.27-1.33 × as long as wide, long-oval; shoulders angulate to base and to lateral margins, obliquely subtruncate; sides sub-parallel; apex broadly rounded. Striae punctate, punctures small, hidden by appressed scales. Stria 1 at base curved laterally, sutural interval at base enlarged. Odd intervals flat, wide; even intervals weakly elevated, intervals 3, 5 and 7 enlarged at declivity and with low but distinct longitudinal prominence, the biggest at interval 3. Base arched. Elytra in lateral view weakly convex.
Protibiae moderately slender, with straight lateral margin, rounded at apex, with fringe of short and fine yellowish setae, mucronate and not denticulate. Metatibiae with four very small, almost indistinct denticles at apical half; metatibial corbels densely squamous with two, equally long mucros, curved inside. Tarsi slender; segment 2 1.1-1.2 × as wide as long; segment 3 1.3-1.4 × as wide as long and 1.5-1.6 × as wide as previous segment; onychium 1.1 × as long as segment 3. Claws solidly fused in basal half, weakly separate in apical half.
Etymology. The Latin name, meaning with oblique shoulders, refers to obliquely subtruncate shoulders, angled to elytral base and sides.
Differential diagnosis. Pseudocneorhinus obliquehumeralis is similar to P. alternans by the following characters: oval elytra with distinct shoulders, slender antennal scapes, and raised elytral setae on odd intervals only. It can be distinguished from P. alternans by angular rather than regularly oblique shoulders, subdistally distinctly enlarged intervals 3 and 5 each with low longitudinal prominence, and more elongate funicular segments 3 and 4. irregularly angular, small, 8-9 scales across interval width, with small depression in the middle, only narrowly separate. Scales light brownish, elytra in the middle with wide lighter transverse stripe, wider towards sides, elytral declivity with straight transverse dark brownish stripe. Elytra with conspicuous erect setae, longer than half of interval width, lanceolate, apically pointed, longitudinally finely striate, whitish and blackish, with one sparse row on each odd interval and only sporadic setae on even intervals. Setae denser on interval 1 on apical declivity, creating large and wide tuft of setae on prominence on elytral declivity on interval 3, consisting of 18-20 setae and smaller tuft on prominence on interval 5, consisting of 8-10 setae, anterior part of setae on prominence whitish, posterior part blackish. Semierect setae on pronotum and head with rostrum more slender and shorter than elytral setae, sparsely irregularly scattered. Antennae and legs except of basal half of scape with semierect moderately long setae, prominent from outline.
Rostrum (Figs 11-14) short and wide, in males slightly longer than in females, in males 1.03-1.06 × as long as wide, in females isodiametric, from base regularly enlarged to midlength, then tapered anteriad with rounded sides. Epifrons with concave sides, narrowest at midlength, at apex narrower than at base, longitudinally depressed, with somewhat swollen borders. Epistome V-shaped, long, conspicuous, separated by slender carina from frons, in females slightly narrower at apex than apical part of epifrons, in males at apex wider than apical part of epifrons. Frons creating very slender glabrous strip along epistome, bearing five pairs of long, stout setae, obliquely directed anteriorly. Scrobe in dorsal view visible only in apical part as very slender furrow; in lateral view narrow, long, weakly curved, directed towards middle of eyes. Rostrum in lateral view somewhat convex, separated from head by shallow transverse depression. Eyes weakly prominent from outline of head.
Antennae slender. Scapes slender, regularly enlarged in basal half, parallel-sided in apical half, at apex as wide as club. Funicle 1.2-1.3 × as long as scape; funicle segment 1 as long as and as wide as segment 2, each 1.8-1.9 × as long as wide; segments 3-6 1.1 × as long as wide; segment 7 isodiametric.
Elytra (Figs 11-14) 1.15-1.20 × as long as wide, ovoid in dorsal view, at base about as wide as base of pronotum, shoulders not developed; elytra distinctly enlarged posteriad, widest at apical third. Striae distinctly punctate, punctures wide, completely hidden by appressed scales. Even intervals almost flat, odd intervals convex, intervals 3 and 5 at elytral declivity enlarged, forming short longitudinal prominence, on interval 3 larger than on interval 5. Elytra in lateral view distinctly convex.
Protibiae rounded at apex, with fringe of short and fine yellow-brownish setae, mucronate, not denticulate, with straight lateral margin. Metatibiae not denticulate; metatibial corbels densely squamose. Tarsi short, segment 2 1.2-1.3 × as wide as long; segment 3 1.5-1.6 × as wide as long and 1.5-1.6 × as wide as segment 2; onychium 0.8-0.9 × as long as segment 3. Claws solidly fused at basal half, almost parallel-sided at apical half. Penis (Fig. 33) short and wide, in ventral view subparallel-sided with weakly concave sides, base and apex about equally wide, apex truncate with triangular point at the middle; in lateral view short and very wide, slightly curved, equally wide along the whole length with slender, moderately long elongate apex.
Biology. Unknown. Distribution. China: Chongqing, Sichuan (Fig. 52). Etymology. The Latin name, meaning with setae on prominence, refers to the conspicuous tuft of setae on prominence on the elytral declivity.
Differential diagnosis. Pseudocneorhinus setosicallus is similar to P. alternans and P. subcallosus because of its large size and erect setae on odd intervals. From P. alternans, currently known only from females, this species is easily separated mainly by having ovoid elytra without shoulders, with the greatest width in the apical third, long erect elytral setae, conspicuous longitudinal subapical prominence on intervals 3 and 5 bearing very dense tufts of whitish and blackish setae and by slender pronotum. From P. subcallosus, a species with very similar body shape, P. setosicallus is distinguishable by its long, lanceolate erect elytral setae, clearly visible in dorsal as well as in lateral view, while P. subcallosus has elytral setae appressed, subspatulate, barely visible only in lateral view. The subapical tuft on interval 3 consists of at least 15 setae in P. setosicallus but at most 10 in P. subcallosus. As stated below in the key, P. setosicallus also has a longer rostrum and second funicular segment. From P. angustus, a generally smaller species with similar long, conspicuously erect elytral setae, P. setosicallus is distinguishable by shorter, in basal half enlarged rostrum, at mid-length more constricted epifrons, narrower pronotum and other characters given in the key.  Marshall, 1934 Figs 15, 16, 41 Pseudocneorhinus alternans Marshall, 1934: 7 (original  Type material examined. This species was described from an unspecified number of specimens from "Japon". We have studied one probably female specimen, well preserved and 2.94 mm long, deposited in Marshall's collection (BMNH), labeled as follows: Type [printed, circular label with red margin] / Japan G. Lewis 1910-320. Type material examined. This species was described from "Quelques individus. Nagasaki". There is one well preserved, 5.25 mm long, probably female specimen in Marshall's collection (BMNH) below the name Pseudocneorhinus obesus, labeled as follows: Type H. T. [printed, circular label with red margin] / Japan G. Lewis 1910-320. [printed]. Material examined. Other material. JAPAN; 2 ♀♀; G. Lewis leg.; BMNH; 1 ♀; Honshu, Akira Mt., Fyokai-San; 1 Jun. 1972; Takizava leg.; MMTI. Marshall, 1934 Figs 27, 28, 47 Pseudocneorhinus sellatus Marshall, 1934: 8 (original    Type material examined. This species was described from an unspecified number of specimens from "Japon". We have studied one probably female specimen, well preserved and 4.88 mm long, deposited in Marshall's collection (BMNH), with the labels: Type [printed, circular label with red margin] / Japan G. Lewis 1910-320 earlier literature must therefore be revised to check the identity of the specimens. The species can be distinguished by their elytral setae and also by the different shape of the spermatheca. However, we can not confirm that elytral setae are a stable distinguishing character, because material from places other than Japanese islands seems to be variable in this character, but the spermatheca seems to be useable. Based on the spermatheca, we can confirm the occurrence of the both species, P. setosus and P. squameus, in China. Morimoto, 2015 Figs 29, 30, 49 Pseudocneorhinus squameus Morimoto, 2015: 336 (original Marshall, 1934 Fig. 50 Pseudocneorhinus squamosus Marshall, 1934: 6 (original [red, printed]. The other three have the following label data: one specimen with the same violet label as the holotype (without year) and labeled Paratypoid; one female with the same labels as the previous one but 24.7.1937; and one male with locality label Shaowu -Fukien, (500m) J. Klapperich 28.6.7.1937 and the same red "Paratypoid" label. Two specimens, one male and one female, were remounted by us. All these three specimens are designated here as Paralectotypes and provided with one more red and printed label PARALECTOTYPUS Pseudocneorhinus subcallosus Voss, R. Borovec des. 2019.

Key to the Pseudocneorhinus species
The following key separates the new species from all previously described ones. An asterisk (*) after the name means that species has not been studied by us and we know it only from the description.  (Fig. 1).
Elytra more slender, 1.25-1.29 × as long as wide (Fig. 1). Onychium 1.1-1.2 × as long as segment 3. Scape with apex distinctly wider than club. Penis with larger, sharply pointed triangular apex (Fig. 31) (Figs 11, 13). Onychium 0.8-0.9 × as long as segment 3. Scape with apex as wide as club. Penis with smaller, rounded triangular apex (Fig. 33) Only five species are widely distributed between China and eastwards into the Korean Peninsula, the Russian Far East and Japan. We recognize two main distributional ranges in China. One is a longitudinally wide corridor from Heilongjiang to Fujian provinces in the Northeast and the eastern coastal areas. The other is in the Southwest, mainly southern Kansu, southern Shaanxi, Chongqing, and Sichuan provinces. All new species described herein have been discovered in mountainous localities (Fig. 52). Marshall (1934) stated that Pseudocneorhinus hirsutus was found at Kuku-Nor, Tibet. Alonso-Zarazaga et al. (2017) interpreted this locality as Xizang Autonomous Region. The specimens of P. hirsutus examined by us bear the label "China, THIBET, Kuku-Nor, 3200 m, 1898, Hauser lgt." However, Kuku-Nor is the Mongolian name for Qinghai Lake, in Qinghai province. This means that Marshall (1934) referred to the Qinghai-Tibet Plateau rather than to a place in Xizang Autonomous Region. Consequently, the known occurrence of this species is corrected here to Qinghai, Kuku-Nor, which is possibly collected on the lakeside. Morimoto et al. (2015) reported P. squameus from China but gave no locality data from there. Here we confirm that P. squameus occurs in Beijing Municipality and Shanxi province. Other new records are Fujian province for P. minimus and Sichuan province for P. sellatus.