Deltomerodes ovicollis sp. nov.

Yan, Weifeng, Shi, Hongliang, Liang, Hongbin & Shi, Juan, 2021, Two new species of the genus Deltomerodes Deuve, 1992 (Coleoptera, Carabidae, Patrobini) from Xizang, China, ZooKeys 1023, pp. 151-169 : 151

Deltomerodes ovicollis sp. nov. Figs 1 , 2-6 , 7-10 , 11-14

Type locality.

China, Xizang, Mêdog County, Doxong La (= Duoxiong La, 29.4890°N, 94.9527°E, 4210 m) .

Type material.

Holotype: male ( IZAS), " Xizang, Mêdog County, Doxong La pass, 29.4860°N, 94.9527°E, 4210m, 2011 VII. 22, Yang XD lgt."; " HOLOTYPE ♂ Deltomerodes ovicollis sp. nov., des. YAN & SHI, 2021" [red label]. Paratypes: 1 female ( IZAS), same data as holotype but labeled as paratype; 4 females ( IZAS), " China, Tibet, Lage to Pai Township. foot path. pitfall trap. 29.4897°N, 94.9533°E "; " 4090 m. 2015. 8.8-10. D3. Liang H. B. coll. IOZCAS" .

Diagnosis.

The new species is unique in the genus Deltomerodes in having the following two features: (1) pronotum ovate with posterior margin strongly protruded medially; (2) first antennomere with two or three short accessory setae. In addition, the new species can be diagnosed from congeners by the combination of following characters: head with three pairs of setae between eyes and neck constriction; pronotum lateral margins with one pair of setae before middle, not sinuate before posterior angles; elytral discal pores present on third, fifth and seventh intervals; fifth meso- and metatarsomeres with two pairs of setae ventrally; armature of endophallus consisting of a large loop-shaped proximal copulatory piece and a long spiniform distal piece.

Description.

Habitus as in Figure 1 . Medium-sized for a Patrobini species (L = 9.3-10.7 mm; EW = 3.3-3.5 mm).

General appearance: Dorsal side dark brown to reddish-brown, shiny, without metallic luster; head, pronotum and elytra brown to reddish-brown; mandibles, antennae and legs a little paler, palpi reddish-brown; ventral side largely dark brown to reddish-brown. Dorsal surface of forebody smooth except for basal foveae of pronotum slightly punctate. Microsculpture invisible on head and pronotum, isodiametric on the entire elytra.

Head: Broad and ovate; surface smooth, without distinct punctures. Mandibles not elongated, right mandible with a weakly protruding tooth beneath the basal inner margin; terminal maxillary palpomere broadest in the middle, penultimate and antepenultimate palpomeres with an apical ring of setae; ligula with two adjacent apical setae. Antennae pubescent beginning with third antennomere; first antennomere plurisetose, with two or three short setae and one primary seta distinctly longer than the others; second antennomere glabrous except for apical ring of four to five setae (Fig. 4 ). Eyes small, very slightly convex; temporae tumid, much longer than eye diameter; neck constriction rather deep. Frontal furrows short, shallow but distinct, extended to level of middle of eyes, slightly divergent posteriorly, finely rugose anteriorly. Head with three setae between eyes and neck constriction on each side: one supraorbital seta near middle level of eyes (in one female with one additional seta on one side), two setae between posterior margins of eyes and neck constriction, a little distant from the neck constriction. Mentum with two deep longitudinal foveae basally, tooth narrow and bifid, apical notch shallow; submentum with two setae on each side in both sexes (Fig. 2 ).

Pronotum: Longitudinal ovate, rather narrow, PW / PL = 0.95-1.05, slightly wider than head, PW /HW = 1.12-1.25, widest near anterior third, fairly convex, moderately constricted posteriorly. Anterior margin near straight; anterior angles indistinct, not protruding forward; lateral margins broadly rounded in front, without sinuation before posterior angles; posterior margin strongly protruded, forming a wide median peduncle and short incisions near posterior angles (Fig. 3 ); posterior angles obtuse, their apices slightly pointed outwards. Anterior transverse impression shallow and smooth; basal foveae shallow, finely punctate and wrinkled; disc smooth, median line shallow but distinct, obliterated at both extremities; lateral grooves extremely narrow, not punctate. Lateral margins each with one seta near anterior third, another seta situated a little before posterior angle.

Elytra: Oblong-ovate, convex; EL/EW = 1.62-1.74, EW/ PW = 1.70-1.83, EL/ PL = 2.75-2.95, widest near posterior third, constricted both anteriorly and posteriorly; humeri narrow and oblique, humeral tooth hardly visible; lateral groove narrow. Intervals slightly convex; inner striae well incised, coarsely punctate basally, lateral striae shallower and finer punctate; scutellar stria inconspicuous, only with one or two punctures and a superficial impression, scutellar pore present at base of second interval or second stria; third interval with five to seven setiferous pores, adjoining the third stria or placed on the third interval, the first one near base; fifth interval with three to seven setiferous pores, all in basal half of elytra; seventh interval with four to six setiferous pores in basal half; umbilicate series composed of ten to thirteen pores, basal ones not aggregated.

Ventral side: Largely smooth, lateral areas of mesepisternum very finely wrinkled; mesepimeron narrow, slightly widened laterally, suture separating mesepisternum and mesosternum joins anterior margin of mesepimeron (Fig. 6 ); metepisternum long and narrow, not punctate. Lateral areas of abdominal sternites finely rugose, sternites IV to VI each with one pair of setae near middle; sternite VII with one seta on each side in males and two in females. Female sternite VIII with anterolateral apophyses long, longitudinal depigmentation distinct, posterointernal depigmentation present (Fig. 13 ). Female tergite VIII with anterolateral apophyses quite short; longitudinal carinae absent, transverse ones short and laterally placed, median sclerotization absent, basal depigmentation present, apical depigmentation absent (Fig. 12 ).

Legs: Males with the basal two protarsomeres slightly expanded, second protarsomere distinctly wider than third, which is near triangular; fourth protarsomere slightly bilobed; metatrochanter normal, apex not protruding; all tarsomeres pubescent dorsally; fifth meso- and metatarsomeres with two pairs of setae ventrally (Fig. 5 ).

Male genitalia: Median lobe of aedeagus strongly bent at base, gutter-shaped and opened dorsally; in lateral view apical lamella slightly curved dorsally; in dorsal view apical lamella gradually attenuated towards apex and fairly twisted rightwards, apex round-truncate, forming a faint hook to the right (Fig. 9 ). Armature of endophallus consisting of a large loop-shaped proximal copulatory piece and a long spiniform distal piece (Fig. 10 ). Left paramere larger than right one, both short and gradually contracted towards apex but left one more truncated at apex, both with one long apical seta and one or two short subapical setae (Figs 7 , 8 ).

Female genitalia: Gonocoxite I glabrous; gonocoxite II narrow and slightly curved, blunt-rounded at apex, with two small setae in one fovea at subapical inner margin (Fig. 14 ). Reproductive tract with well-marked annular sclerotized ring about 0.37 mm in diameter on bursa copulatrix, spermatheca small and tubular, spermathecal duct well developed, spermathecal gland inserted near apex of spermathecal duct, much longer than spermathecal duct (Fig. 11 ).

Distribution.

This species is known only from the type locality of Doxong La in Mêdog County, Xizang (Map 2 ) .

Etymology.

The scientific name of the new species comes from Latin and refers to its very special ovate pronotum.

Remarks.

Zamotajlov (1999) recognized five species groups in the genus Deltomerodes , among which three were from China. Most of the Chinese species (four of six) were assigned to the Deltomerodes murzini -group, whereas D. zolotichini and D. memorabilis are in their own species groups. According to Zamotajlov (1999), the new species can be keyed to the Deltomerodes murzini -group for some characters: (1) head with less than four pairs of setae between eyes and neck constriction; (2) pronotum not cordate, without distinct sinuation before posterior angles, sides with one seta in anterior third. However, it is quite different from all other members of this species group not only for its very special pronotum shape (ovate with posterior margin strongly protruded) but also for other important features: (1) fifth meso- and metatarsomeres with two pairs of setae ventrally vs. with three or four pairs of setae in other species of this group; (2) first antennomere with two or three short accessory setae vs. without short setae; (3) seventh elytral interval with four or more discal pores vs. with one or two setiferous pores. Additionally, the new species is more similar to D. memorabilis mainly in aspects of the humeral shape and in the chaetotaxy of the elytral intervals and fifth tarsomeres, though the differences between the two species are rather distinct following the key. Thus, the new species may be either assigned to the Deltomerodes memorabilis -group or assigned to its own group.

Figures

Figure 1. Deltomerodes ovicollis sp. nov. (holotype). Habitus and labels (the white dots represent the setiferous pores on the left side of the specimen). Scale bar: 1.0 mm.

Map 2. Distribution map for Deltomerodes ovicollis sp. nov. and adjacent taxa: D. ovicollis sp. nov. (red); D. zolotichini zolotichini (blue); D. zolotichini similis (magenta).

Figures 2 - 6. Deltomerodes ovicollis sp. nov. (holotype) 2 labium 3 pronotum 4 first two segments of antenna 5 lateral side of the fifth metatarsomere 6 ventral side of thorax. Scale bars: 0.5 mm (a for 2, 3, b for 4 - 6).

Figures 7 - 10. Deltomerodes ovicollis sp. nov. (holotype) 7 left paramere of aedeagus (dotted line shows damaged apex) 8 right paramere of aedeagus 9 median lobe of aedeagus, left lateral view (9 A), dorsal view (9 B) 10 endophallus of aedeagus, left lateral view (10 A), dorsal view (10 B). Scale bar: 0.5 mm.

Figures 11 - 14. Deltomerodes ovicollis sp. nov. (paratype female) 11 female reproductive tract 12 female tergite VIII 13 female sternite VIII 14 gonocoxa, right lateral view (14 A), dorsal view (14 B). Scale bars: 0.5 mm (a for 11 - 13, b for 14).