Omophorus (Sinomophorus) rongshu, Wang, Zhiliang, Alonso-Zarazaga, Miguel A., Ren, Li & Zhang, Runzhi, 2011

Wang, Zhiliang, Alonso-Zarazaga, Miguel A., Ren, Li & Zhang, Runzhi, 2011, New subgenus and new species of Oriental Omophorus (Coleoptera, Curculionidae, Molytinae, Metatygini), ZooKeys 85, pp. 41-60 : 43-52

Omophorus (Sinomophorus) rongshu sp. n. Figs 123

Description

(holotype, except where indicated). Measurements (in mm): Standard length: 4.95. Rostrum: length: 1.08, maximum width: 0.43. Pronotum: median length: 1.09, maximum width: 2.01. Elytra: median length: 4.10, maximum width: 3.70.

Integument. Reddish brown, base and apex of elytra, a broad sutural band, venter of femora, parts of meso- and metasternum and their pleurites, and part of the 1st ventrite dark brown; apical margin of 2nd-4th ventrites and the whole 5th, antennal scape and funicle testaceous.

Vestiture on elytra of scarce, short, very fine, pale piliform scales, most numerous on extreme base of 2nd-3tr interstriae, on head and pronotum formed by the same scales, but denser and thicker, creamy to tan, on disc directed cephalad, on sides directed to midpoint of pronotum; on legs as on head and rostrum, but larger and whiter; on ventral areas, coxae, trochanters and ventral part of femora, vestiture of bifid piliform scales, each scale with a common stalk hardly longer than basal width of each branch. Sclerolepidia absent. Remnants of waxy-pulverulent, creamy to tan exudate in some parts of elytra and pronotal base.

Rostrum (Figs 3-4) 0.99 × as long as pronotum, in dorsal view 2.51 × as long as wide, with apex slightly bisinuate, sides subparallel, densely punctate, except smooth and shiny apical tenth, metarostrum with a median sulcus prolongated basad to hind margin of eye, ending apically at antennal insertion level; in side view metarostrum dorsally depressed, prorostrum a little narrowed to apex, ventral margin straight, forming a soft curve with underhead. Scrobes dorsally visible at apex, in side view almost straight, deep, narrow, upper margin directed towards lower angle of eye, but not reaching it, becoming obsolete, lower margin convergent with upper and evanescent; scrobes in ventral view not convergent, obsolescent against under margin of eye. Underside of rostrum densely punctate, with three low keels, the lateral ones ending at insertion level, the median one distally fusing with the submentum. Labium ca. 1.5 × as long as wide, sides weakly rounded, medially longitudinally impressed, apically truncate to weakly emarginate, 1.5 × as long as labial peduncle, labial palps invisible; maxillary palp 3-segmented. Mandibles tridentate, overlapping. No postmandibular sensory setae.

Head in dorsal view subglobular, densely and subrugosely punctate, medially sulcate up to occiput, frons narrow, ca. 0.5 × as wide as rostral apex, in side view frons weakly convex; eyes moderately large, slightly convex, ca. 1.5 × higher than long, transversely elliptical, some 16 ommatidia in longitudinal diameter.

Antennae inserted at basal 0.49 of rostrum, with scape 5.58 × as long as wide and 1.09 × as long as funicle, slightly clubbed and bent at apex, glabrous except pubescent apical club, 1st desmomere 1.7 × as long as wide, obconical, well separated from 2nd, this also obconical and 1.56 × as long as wide, but slightly narrower than 1st and 0.82 × as long as it, desmomeres 3 tr– 6th 2.0 × as wide as long, tightly packed and increasing in width apicad, 7th annexed to club, 3.0 × as wide as long and covered with a denser vestiture than others; club of 3 segments, suture between 1st and second obliterated, almost invisible, that between 2nd and 3tr narrow but visible, so that apparently the club is bisegmented, last segment 1.3 × as long as remainder of club, whole club 2.54 × as long as wide, 1.69 × as long as funicle.

Pronotum in dorsal view 1.85 × as wide as long, its base 1.79 × as wide as apex, bisinuate, with marginal keel, median lobe weakly and widely emarginate, surface densely punctate at base and on disc, punctures oblong, ca. 60 μm long, separated half their diameter or less, on sides and apical third smaller, 30 μm or less, widely spaced, a small median smooth and shiny tubercle just behind the faint collar constriction. Basal angles rounded-subtruncate.

Mesonotum (Fig 18). Scutellum 0.82 × as long as wide, large, trapezoidal, wider at base, sides sinuate, apex subtruncate, slightly bituberculate, each tubercle with short setae, surface densely and rugosely punctate, punctures as small as those on apex of pronotum. Prephragma well developed, strongly prominent, antecostal sutures straight, meeting at middle in an obtuse V, mesoscutum smaller than scutellum. Axillary cord laterally prominent as a round lobe, joining in a soft curve the postero-lateral margin of mesonotum.

Metanotum (Figs 14-15). In general shape, anterior part forming a vertical wall with a very narrow, transversal opening. Anterior margin of prescutum with a pair of prominent teeth and a deep median notch. Antero-medial margin of allocrista rounded. Scutellar groove wide, its anterior margin widely open with a small elevation on each side, without anterior bridge, with a median longitudinal obtuse elevation, not keeled. Metascutum about as large as metascutellum, separated from it by a straight postero-medial margin. Postero-lateral margin of metanotum with a strong, laterally and slightly caudally pointing tooth, and a round lobe in front of it bearing two teeth. Postnotum small, strongly transverse, well separated from metascutum and metascutellum.

Elytra (Fig 1) 1.11 × as long as wide, base of interstriae 2-4 convergent and prominent cephalad, covering base of pronotum, humeri moderately convex, sides of elytra widening from under the calli, widest at middle, uniformly rounded to apex, apices very narrowly rounded separately, sutural angle small, subacute. Striae 10, widely sulcate, with rows of small inner punctures, forming irregular aggregates separated by bridges uniting interstriae, giving a moderately foveolate aspect, each puncture with a subarcuate seta hardly as long as half the interstrial ones, and finer; interstriae weakly convex, subequal in width, with 2-3 irregular rows of extremely minute punctures (less than 6 μm in diameter), surface almost smooth, weakly microreticulate, first interstria strongly microreticulate, transversally rugose, more convex behind scutellum. Striae at apex join 1+10, 2+9, 3+8, 4+5, 6+7, 10th marginal and obsolete in apical fourth, with a strong outer keel in basal ¾, 11th interstria completely facing ventrally from base up to level of abdominal suture III; at base, 1st shortened and reaching the level of apical third of scutellum, 2nd-4th convergent towards basal lobe of elytron. Internal submarginal fold well developed, strongly curved. Sutural flanges dissimilar, that on the left elytron wider, in basal part turned vertical, that on the right elytron narrower, parallel to elytral surface in its whole length. Underside with small, inconspicuous superficial file of stridulatory system type 1 ( Lyal and King 1996) near apex.

Metathoracic wing (based on 2 paratypes) (Fig. 9). A typical curculionid wing, ca. 3.1 × as long as wide, with the surface covered with microtrichia. C, Sc and R without special characters. Rr undifferentiated in the apical half, rm and rms appearing as a single unit, rfi, rcm and rc forming a single plate in which rcm is weakly distinguishable as a small elongate trait. 1rs and 2rs form separate plates, united posteriorly to rsc. R3 present, thin, incomplete; anterior stripe thinner than the postradial stripe. M1 thin, parallel to mst, and joining it near apical third of mst length. Cu uniting to Cu1 with a strongly arched loop, Cu1 following to near margin as af. 1A1 and 1A2 absent. A strong, weakly arched, not reaching margin, 3A very weak, stripe-like, not closing ac. Basal sclerites: Br and Bsc fused.

Ventral area. Procoxal cavities separated from front margin of prothorax a distance twice that separating them from hind margin. Mesosternum very short, vertical in front, forming a steep angle in side view; meso-metasternal median suture not evident, replaced with a weak transverse sulcus; mesepisternum fused to mesosternum, mesosternal suture indicated by a small depression; mesepimeron triangular, fused to mesepisternum, mesopleural suture visible, anteriorly deepened, not functional. Metasternum fused medially to mesosternum, suture not visible, replaced with a weak sulcus, this joined in middle by a median longitudinal sulcus running from base to apex of metasternum, deeper at apex; a prominent transverse tubercle in front of metacoxae, forming a vertical step; metepisternum elongate-trapezoidal, apical angles a little produced laterally, the upper angle fitting in a small notch on the elytral costal margin, basal margin rounded; metasternal suture visible, complete, functional; metepisternum much reduced, covered by elytron. Abdomen (Fig 12) with 2nd ventrite as long as 3tr medially, 4th shorter (0.9 ×), 5th 1.19 × as long than 4th and 4.97 × as wide as long, 1st ventrite 1.94 × as long as second in median length, 1.11 × as long as 2nd in postcoxal length. First ventrite strongly raised across basal margin, 5th weakly depressed across middle. Suture I deep, weakly bisinuate, sutures II-IV functional, straight, slightly curved backwards at outer angles.

Metendosternite (based on 1 paratype) (Fig 10): Stalk weakly trapezoidal and transverse, anterior part of longitudinal flange shorter than posterior, hemiductus robust, projection as long as wide, furcal arms long, apically clearly bifurcate, anteroventral branch shorter than laterodorsal one. Insertions of anterior tendons at the same distance as angles formed by margins of stalk and sheath.

Legs. Procoxae contiguous, subconical. Mesocoxae separated by a distance 1.4 × the mesocoxal diameter. Mesocoxae and metacoxae separated 0.8 × the mesocoxal diameter. Metacoxae separated 0.5 × the distance between mesocoxae. Metacoxae transversely elongate, reaching the outer front angles of 1st ventrite, outer part covered by meeting lobes of metasternum and 1st ventrite, thus apparently very narrow. Trochanteral seta present. Femora edentate, robust (profemur 3.38 × as long as wide). Tibiae robust (protibia 4.06 × as long as wide), sides subparallel, inner margin very weakly bisinuate, not crenulate. Tibial unci raising from middle part of talus, leaving an outer angle and an inner praemucro, metatibial uncus shorter than others. Tibial comb complete, on almost transverse margin of talus. Front tibiae with a patch of dense golden setae near front inner apical angle, above comb, a grooming area also present in apical inner margin. Tarsomeres moderately robust, 1st protarsomere 1.67 × as long as wide, 2nd 0.73 ×, 3tr 0.65 ×, with complete ventral sole, except for narrow glabrous midline, onychium 3.7 ×, surpassing lobes of 3tr by 0.38 × length of onychium. Claws free, simple, divaricate, short and robust, as long as onychium height in side view.

Abdominal tergites (based on 1 paratype) (Fig 13). Tergites I-III weakly sclerotized, submembranous; spiracular sclerites a little more sclerotized, round; tergites IV-VI more sclerotized, mostly in two marginal fasciae on each side of front margin; tergite VII (prepygidium) trapezoidal-semilunate, front median area with a transverse keel, the keel triangularly prominent at middle and apex of prominence bearing 2 small tubercles (plectra of stridulatory system type 1 of Lyal & King (1996)), the left one more developed than the right one, one transverse binding patch near the front angles; tergite VIII (pygidium) (Fig 16) more or less semicircular, front angles prominent, with one basal binding patch each, the apical area densely punctate, hispid.

Male genitalia and terminalia (based on 1 paratype). Sternite VIII (Fig 17) undivided, semilunar, apex widely emarginate, more sclerotized basally, the membrane between this and the sternite IX with 2 very small, dot-like sclerotizations. Sternite IX with hemisternites fused between them and to the front margin of the spiculum gastrale to form an irregular subpentagonal plate, widely notched caudad; spiculum robust, directed towards left side of abdomen, almost straight, apex weakly hooked. Penis (Fig. 20) in dorsal view with tube 1.32 mm in length and temones 1.17 mm, tube ca. 3.2 × as long as wide, apex ogival, subacute, sides rounded, with a small apical peg, widest at basal 4th, temones fused; in lateral view moderately and uniformly curved at sides, highest at basal 3tr, apical peg rounded; a subtobtuse ventral longitudinal keel present. Endophallus without large sclerotized structures, covered with very dense, minute (2.5 μm long) teeth, some longer teeth forming several diffuse longitudinal streams. Tegmen (Fig. 19) with ring narrow, manubrium about as long as parameroid lobes, these widely spaced at base, lanceolate, slightly asymmetrical, apex and inner margin desclerotized, covered with minute translucid microchaetae, those at apex ca. 25 μm long.

Variation. Male paratypes.

Measurements (in mm) (n=7): Standard length: 4.40-5.30 (mean= 4.85). Rostrum: length: 1.08-1.22 (mean= 1.15), maximum width: 0.38-0.46 (mean= 0.42). Pronotum: median length: 0.91-1.20 (mean= 1.06), maximum width: 1.90-2.20 (mean= 2.05). Elytra: median length: 3.70-4.30 (mean= 4.00), maximum width: 3.05-3.95 (mean= 3.50).

Rostrum 0.98-1.11 × as long as pronotum, in dorsal view 2.57-2.88 × as long as wide, sides varying from subparallel to visibly but weakly widened towards apex in an almost straight line. Pronotum 1.79-2.09 × as wide as long in dorsal view. Scutellum with sides more or less straight and apex more or less rounder to weakly notched, the apical tubercles more or less separated and variably prominent. Elytra 1.08-1.25 × as long as wide.

Female paratypes.

Measurements (in mm) (n=7): Standard length: 4.60-5.30 (mean= 4.95). Rostrum: length: 1.42-1.56 (mean= 1.49), maximum width: 0.38-0.44 (mean= 0.41). Pronotum: median length: 1.04-1.28 (mean= 1.16), maximum width: 1.95 -2.30 (mean= 2.13). Elytra: median length: 3.70-4.55 (mean= 4.13), maximum width: 3.20-3.90 (mean= 3.55).

As males, but rostrum (Figs 7-8) 1.21-1.37 × as long as pronotum, in dorsal view 3.55-3.74 × as long as wide, in dorsal view prorostrum glabrous, with sides gently curved, constricted at middle, minutely and sparsely punctate, punctures weak, metarostrum with sides weakly converging to mesorostrum, punctate and pubescent as in male; in side view straight, dorsal and ventral margins of prorostrum parallel; underside almost impunctate, subglabrous. Head with frons ca. 0.63 × as wide as rostral apex. Antennae inserted at basal 0.42 of rostrum, shorter, scape about as long as funicle, club 1.25 × as long as funicle.

Pronotum 1.79-1.95 × as wide as long in dorsal view. Elytra 1.05-1.25 × as long as wide.

Tergites VII and VIII (Fig 11) similar to those of male, tergite VIII less convex, semicircular, rather flat, with one small (functional?) spiracle on each side.

Female genitalia and terminalia (based on 2 paratypes) (Fig 22): Sternite VIII heart-shaped, with a wide apical sinus, most of it membranous and thin, laterally sclerotized, setose and with multiple sensilla, medially broadly membranose to base; basal convergent margins a little folded and sclerotized; spiculum absent. Ovipositor with gonocoxites robust (ca. 3.5 × as long as maximum width), moderately curved, weakly constricted at middle, rounded at apex, without styli, a small apicomedial fovea carrying a short, thick tuft of setae; dorsal surface with a membranous elongate triangular area, pointing apicad; ventral surface with a rounded longitudinal finlike flap; outer surface covered with moderately dense sensilla. Bursa irregular, large, wrinkled, with some small irregular sclerotized areas near the point of union of the spermathecal duct and of the oviduct. Spermatheca C-shaped, large (ca. 0.43 × as long as the 8th sternum wide), with a long, apically rounded cornu not clearly differentiated from the spermathecal body (nodulus), except for the dorsal gibbosity, collum about as long as nodulus, ramus absent. Spermathecal gland ca. 3.2 × as long as maximum length of spermatheca.

Common variability.

The specimens show some variation in colour, mostly a lesser presence of the dark brown colouration on elytra, restricted to some basal spots and an apical patch, or to a lining of the bottom of the elytral striae, the apical margin of the ventrites, the sides of pronotum and the basal two thirds of the rostrum, the other areas remaining reddish brown, or all the head and rostrum may become also of the same colour. Legs may also show different variations. No variation has been noticed in vestiture, but the pronotal median tubercle may be more or less covered with punctures in different individuals.

Material examined.

Holotype: ♂: (white, handwritten): 云南路西 [ Yúnnán Lùxī] / 1958.6.26; (white, handwritten): 中国科学院 ，榕树 [ Zhōngguó Kēxuéyuàn, róngshù] 575; (white, printed): IOZ (E) 909962. Paratypes (12♂, 7♀): same data as holotype: 2♂ labeled IOZ(E) 909960, IOZ(E) 909961 and 1♀ labeled IOZ(E); 1♂, same data as holotype except date 1958.6.27 and IOZ(E) 909962 with same data as holotype except for collecting date: 1958.VI.27; 8♂, same data as holotype except date 1958.6.30 and IOZ(E) 909948, IOZ(E) 909949, IOZ(E) 909950, IOZ(E) 909954, IOZ(E) 909957, IOZ(E) 909958, IOZ(E) 909959, IOZ(E) 909963; 6♀, same data as holotype except date 1958.6.30 and IOZ(E) 909946, IOZ(E) 909951, IOZ(E) 909955, IOZ(E) 909956, labeled IOZ(E)1799147, IOZ(E)1799150; 1♂: (white, handwritten): 云南瑞丽 [ Yúnnán Ruìlì] 1958.7.6; (white, handwritten): 中国科学院 ，榕树 [ Zhōngguó Kēxuéyuàn, róngshù] 688; (white, printed): IOZ(E) 909964.

Holotype and all paratypes to be conserved in IOZ-CAS, except one male and one female paratype to be deposited in MNCN-CSIC (Madrid) and another paratype couple in the NHM (London).

The first character used to write the second place name ( Lùxī) is incorrect. It should have been 潞.The only Yunnanese locality named 路西 is found at more than 2,000 m height.

Etymology.

The specific epithet is a pinyin transliteration (without diacritics) of the indication of the host plant on the labels, róngshù (榕树), which is applied to Ficus microcarpa L.f. ( Moraceae ) (Zhou and Gilbert, 2003). It is used as a noun in apposition.

Distribution and habitat.

The species is known from two close localities in Yunnan province (P.R. China): Lùxī (575 m) and Ruìlì (688 m), separated by 87 km, but see below (Fig 23). No exact data about the biology of this species are known, except the identity of the host plant on which the specimens were captured, a common tree below 1900 m in the area, and widely planted as a shade tree ( Zhou & Gilbert 2003).

Note.

One male has not been included in the type series, because it differs from the specimens collected in the two above mentioned localities as follows: Rostrum (Figs 5-6) more visibly widened towards apex, more robust (2.49 × as long as wide, 0.93 × as long as pronotum). Scape more robust (5.30 × as long as wide) but longer (1.23 × as long as funicle), 2nd desmomere more robust (1.36 × as long as wide), 3tr-6th desmomeres 2.7-3.7 × as wide as long, club more robust (2.39 × as long as wide) and shorter (1.42 × as long as funicle). Pronotum narrower, in dorsal view 1.67 × as wide as long. Scutellum as long as wide. Abdomen with 2nd ventrite 1.2 × as long as 3tr, 4th as long as 2nd, 5th 4.65 × as wide as long, 1st ventrite 1.66 × as long as 2nd in median length, 0.89 × as long as 2nd in postcoxal length. Mesocoxae separated by a distance 1.2 × the mesocoxal diameter. Profemur more robust, 3.0 × as long as wide, protibia more slender (5.43 × as long as wide. Onychium surpassing lobes of 3tr tarsomere by 0.5 × length of onychium. Penis (Fig 21) similar, but more constricted medially in dorsal view, and ventral angle sharper (in cross-section).

Label data for this specimen are as follows: (white, two marginal faded red lines, pencil handwritten): 黑尾棕象甲 [Hēi Wěi Zōng Xiàng Jiǎ] / 新平 [ Xīnpíng]; (white, faded red lined, field names printed, handwritten): 新平 [ Xīnpíng];，80年; (white, printed): IOZ(E)1799122. The first label corresponds to an intent of identification in Chinese (the brown weevil with black tail) and the locality; the second repeats the locality Xīnpíng (Yunnan, China) and includes only the year of collection [19]80. This locality is separated from the closest one, Lùxī, by ca. 347 km (Fig 23).

Although some of the differences, notably those of the proportions of the ventrites and of the antennomeres, could be taken as enough to describe a different species, we prefer to wait until a series from the latter locality can be studied. These differences may be individual or populational, and the erection of a new taxon unjustified.