Orthotemnus longitarsus Omar & Zhang

Omar, Youssef Mohamed, Zhang, Runzhi & Davis, Steven R., 2015, A new species of the genus Orthotemnus Wollaston, 1873 (Coleoptera, Curculionidae, Cossoninae) from China, ZooKeys 472, pp. 103-116 : 105-109

Taxon classification Animalia Coleoptera Curculionidae

Orthotemnus longitarsus Omar & Zhang sp. n. Figs 1-4, 5-11, 12-18, 19-22, 23-31, 32-37, 38-40

Diagnosis.

Rostrum widening after antennal insertion; scapes passing posterior margin of eye and reaching postocular constriction; temples swollen; forehead with short median furrow; sutural striae deep and depressed near scutellum; intervals smooth, equal, convex, with a single row of fine punctures, wider than striae; humeri truncate, quadrate; tarsi longer than tibiae.

Description.

Measurements (male): BL: 3.29-3.40 mm; EL: 2.33-2.38 mm; EWB: 1.02-1.08 mm; EWW: 1.02-1.08 mm; PL: 0.96-1.02 mm; PW: 0.90-0.94 mm; RL: 0.52-0.55 mm; RWA: 0.31-0.34 mm; RWB: 0.25-0.30 mm; AL: 0.90-0.94 mm; ASL: 0.40-0.42 mm; AFL: 0.30-0.31 ACL: 0.20-0.22; ACW: 0.12-0.14 mm. Measurements (female): BL: 2.58-2.80 mm; EL: 1.70-1.90 mm; EWB: 0.84-0.96 mm; EWW: 0.84-0.96 mm; PL: 0.88-0.90 mm; PW: 0.77-0.78 mm; RL: 0.48-0.50 mm; RWA: 0.26-0.28 mm; RWB: 0.19-0.20 mm; AL: 0.70-0.90 mm; ASL: 0.32-0.40; AFL: 0.20-0.30; ACL: 0.13-0.20; ACW: 0.10-0.11 mm.

Body (Figs 1-5) oblong, curved, glossy.

Colour dark reddish-brown; rostrum, antennae and legs paler brown than body.

Rostrum (Figs 6, 10) long, more than 2 × longer than width at base, more or less 0.5 × as long as pronotum; narrow before antennal insertions (basal half), sides parallel, curved dorsally, widening after antennal insertion (in apical half), curved ventrally at antennal insertions; antennae inserted after middle of rostrum; with fine, subcircular, shallow punctures along dorsum, becoming oblong, denser towards apex; narrower at base than at apex; scrobes (Fig. 10). well-defined, deep, short, located in middle of rostrum, dorsal margin slightly lower than upper margin of eye, ventral margin black, visible in dorsal view.

Mouthparts. Maxillae (Fig. 25) with palpiger with large, slender seta near basolateral margin; galeo-lacinial complex with several large, tooth-like setae along margin, a few smaller, slender setae near base. Labium (Fig. 26) with prementum elongate, lacking setae; 1st segment of palpus with 2 setae, 2nd segment with 1 seta, 3rd (apical) segment lacking setae. Right mandible (Fig. 24) with 3 teeth and a small molar region, primary tooth largest, second and third teeth smaller; left mandible (Fig. 23) mainly with large primary tooth and molar region, other teeth reduced to small ridges.

Antennae (Figs 10-12) pale, long, glossy brown, clubs pilose; scapes slightly bent at middle, thick and widening in distal third, widened part with sparse, shallow, oblong punctures with fine suberect setae, smooth, passing posterior margin of eye, approaching postocular constriction, approximately as long as or slightly shorter than funicle; clubs compact; funicles with all segments with few fine, erect setae, loose, segment 1 stout, longer than wide, segments 2-5 subequal, 6 and 7 wider than long, 7 wider than 6; clubs (Fig. 11). longer than wide, oval, slightly laterally flattened, 3-segmented, setigerous, setae suberect towards apex, acuminate.

Head oval, laterally constricted behind eyes, constriction weak dorsally, temples swollen, with subcircular punctures, fine sparse punctures behind postocular constriction, wrinkled, glossy; forehead slightly convex, broader than rostral base, with clear circular punctures, interspaces 2-3 × puncture diameter, with short median longitudinal furrow; vertex bulbous, convex, wrinkled. Eyes oval, widely separated, convex, with coarse, convex facets.

Pronotum conical, anteriorly constricted, deep laterally but weak dorsally, forming collar with large, circular punctures throughout, punctures separated by approximately 1-2 × their diameter, with abbreviated smooth median line not reaching anterior and posterior margins, dorsally and laterally convex, truncate along posterior margin.

Mesonotum (Fig. 29) typical of Cossoninae; axillary cord enlarged, lateral margins rounded.

Scutellum visible, transverse-oblong, smooth, dull.

Metanotum (Fig. 30) with metascutum reaching posterior margin of notum; scutellar groove nearly reaching posterior margin of notum; allocrista angular at anteromesal angle.

Metendosternite (Fig. 28) stalk slightly taller than wide; longitudinal flange short; furcal arm slender, bifid at apex; hemiductus slender.

Proventriculus as in Fig. 27.

Elytra (Figs 5, 9. glossy, long, disk convex, lateral margins parallel until declivity, base truncate, slightly broader than pronotal base; striae with large, deep circular punctures, punctures separated by approximately 1-1.5 × puncture diameter, first stria (sutural stria) deeper and depressed near scutellum; intervals smooth, equal, convex, with a single row of fine punctures, wider than striae; sutural interval deeper and depressed near scutellum, dilated at declivity to apex, interval 3 elevated caudally of declivity, with more than one row of fine punctures; intervals 4, 5 and 6 connected slightly caudally of declivity but not reaching apex; interval 9 forming oblique, ridged elevation caudally of declivity and connected to interval 3, not reaching apex; humeri truncate, quadrate.

Hindwings (Fig. 31) slender, lacking jugal area (anal lobe); Rr slender, abbreviated, not reaching rcm; rc absent; 1rs triangular and larger than 2rs; R3 absent; Cu1 not reaching posterior margin; r-m absent; A simple, other anal veins absent.

Thoracic sterna flat; prosternum wrinkled, with deep circular punctures; procoxae separated by 0.5 × diameter of coxa; mesoventrite flush with prosterum, base bisinuate, mesocoxae separated by approximately coxal diameter; metaventrite transverse, longitudinal sulcus from base to beyond middle, with circular punctures spaced by 2-3 × diameter of puncture, meta coxae separated by slightly less than 2 × diameter of coxa; dorsal margins of metaventrite serrate (sclerolepidial setae absent, though setal sockets present; Figs 7-8).

Legs (Figs 19-22). Ffemora glossy, robust along distal two-thirds, with small, circular, sparse punctures, separated by approximately 2-4 × puncture diameter, slightly less than 2 × length of tibia; tibiae with smaller, similarly spaced punctures, straight, nearly uniform in width; uncus small, at outer apical margin, approximately 0.5 × as long as tarsomere 5, praemucro at inner apical margin covered by a small tuft of setae; tarsi longer than tibiae, 5-segmented; segments 1-3 with long, pale yellowish setae, 1 2 × longer than wide; 2 subequal in length and width; 3 wider than long, notched; 4 small, 5 longer than others combined, curved, dorsally convex, glossy, with appressed pale yellowish setae; claws simple, free.

Abdomen.Tergites (Figs 13-16) with microtrichial wing-locking patches restricted to posterior half of tergites 2-5 and present on most of tergite 6; two linear rows of plectra present on tergite 7 ( Lyal and King 1996). Ventrites (Fig. 17, 18). glossy, 1 and 2 with large, circular punctures, punctures separated by 2-3 × their diameter; 1 broader than 2, projecting between metacoxae, 1 and 2 clearly separated; 3 and 4 narrow, equal, each with two rows of punctures, basal row with large, deep, oblong punctures, apical row with fine small punctures, with fine suberect setae apically; 5 transverse, posterior margin rounded, with large, oblong, deep punctures at base, punctures becoming sparse and subcircular apically with some appressed setae.

Male terminalia and genitalia (Figs 32-37). Spiculum gastrale of sternite IX with flattened, expanded apex; apex approaching size of sternite at base. Sternite VIII divided, with 2 setae on each hemisternite. Tegmen complete; manubrium nearly 0.5 × length of tegmen. Penis with temones ca. 4.5 × body of penis; apical margin setose; endophallus (internal sac) extensive, greater than 0.5 × length of temones, bearing several internal sclerites from approximate middle of endophallus to its apex.

Female terminalia and genitalia (Figs 38-40). Gonocoxites of typical form; oblong; styli elongate, narrow. Spermatheca approximately crescent-shaped. Sternite VIII with spiculum ventrale gradually narrowing towards apex; base with many setae, setae mostly bifid at middle of base and mostly simple laterally; many microtrichia along basal region of sternite anteriorly of setae.

Material examined.

Holotype: male: China: Jiangsu: Jiangsu Province, Nanjing, Zijingshan, 32.30°N, 118.49°E, 05 III 2008, collected by Liang Ding (IOZ). Paratypes: 4 ♀ and 4 ♂: same data as holotype; found under trees in park.

Etymology.

The specific epithet is a combination of the Latin word longus and the Latinized Greek word tarsus, referring to the longer tarsus in relation to the tibia; it is a noun in apposition.

Distribution.

China: Jiangsu Province: Nanjing, Zijingshan.

Sexual dimorphism.

The female (Figs 3-4) is smaller than the male (Figs 1-2), and its rostrum is slightly shorter and slenderer than that of the male. Males also have concave first and second ventrites, the first slightly more projected between the metacoxae than in the female.