Lacon diqingensis, Prosvirov, Alexander S., 2016

Prosvirov, Alexander S., 2016, New and little-known species of the genus Lacon Laporte, 1838 (Coleoptera: Elateridae) of China, Zootaxa 4132 (3), pp. 373-382 : 374-375

Lacon diqingensis sp. nov.

( Figs. 1 , 4, 7)

Type locality. Chinna, Yunnan Province, Diqing Prefecture, Shangri-La City County.

Type material. Holotype, female, China: “Yunnan, Lijiang->Shangrila, 214 Ntn. Road,WSW of Edi Vill., 27°20'03''N, 99°52'34''E, 30.V.2013, H= 3365 m, I.A. Belousov, I.I. Kabak, G.E. Davidian leg.” [ China, NW Yunnan, Diqing Prefecture, Shangri-La City County, Lijiang->Shangrila, 214 Ntn. Road,WSW of Edi Vill., 27°20'03''N, 99°52'34''E, 30 May 2013, H= 3365 m, I.A. Belousov, I.I. Kabak, G.E. Davidian leg.] ( ZISP).

Diagnosis. L. diqingensis sp. nov. is closely related to L. lijiangensis sp. nov. It can be easily distinguished from this species by the larger body (body lengths are 13.20 mm and 9.50 mm, respectively), by different proportions of the pronotum and the elytra (ratios of lengths of the pronotum/lengths of the elytra are 0.46 and 0.50, respectively; ratios of widths of the pronotum/widths of the elytra are 0.94 and 1.00, respectively), by the different sculpture of the pronotum, by the distinct shape of the hind and front angles of the pronotum, by the different shape of the scutellum, by the incompletely reduced wings and by the different structure of the sclerotized plates in the bursa copulatrix. The new species is apparently rather distantly related to all other species of the genus.

Description. Female: Length 13.20 mm; width 4.25 mm. Body flattened, rather broad, oblong. Weakly shining, almost matt, all body dark reddish brown; hind angles and sides of pronotum, disc of elytra lighter; beaded part of prosternal lobe, base of pronotum, scutellum along margin, anterior slope of elytra and elytral suture darkened; maxillar and labial palpi and labium light brown. Body covered with golden, rather dense and short, recumbent scale-like setae; pubescence on dorsum and in basal 2/3 of prosternum distinctly longer than on other parts of body.

Head. Clearly wider than long (length/width 0.65); frons deeply depressed almost over all width; this depression extended up to middle part of vertex, being, however, shallow and obsolete medially. Punctures coarse and dense, notably smaller than on pronotum; intervals between punctures subequal to or smaller than half as great as diameter of one puncture. Antennae reaching slightly beyond middle of pronotum, weakly serrate from antennomere 4. Antennomere 1 long, dilated; antennomere 2 almost globose, 0.8 times as long as antennomere 3; antennomere 4 1.2 times as long as antennomere 3; antennomeres 5 to 10 subequal in length, about 0.9 times as long as antennomere 4; last antennomere oblong, subapically slightly tapered (ratio of length/width of antennomeres from 1 to 5 as 2; 1; 1.5; 1.4; 1.2, respectively). Pubescence of antennae rather dense, setae slenderer and shorter than on other dorsal surfaces; recumbent setae interspersed with some erect ones. Mandible with tooth; last segment of maxillar palpus noticeably broadened at apex, almost obtriangular.

Thorax. Pronotum more than 2.5 times as wide as head, slightly wider than long (length 3.80 mm; width 4.00 mm), widest near middle, narrowed toward front angles more sharply than toward hind angles, notably sinuate before hind angles; weakly convex, flattened laterally. Front angles of pronotum rather short, rounded, extending to and covering half of length of eyes. Median impression on disc of pronotum very shallow, but extended from base almost to anterior margin. Disc of pronotum with two pairs of foveae, first one near middle, second one near base; distinct transverse impressions situated sublaterally near anterior margin of pronotum; obsolete lateral impressions situated near middle of pronotum. Hind angles of pronotum depressed, short, broadly rounded at apex, clearly divergent, without carina. Punctures coarse, dense; intervals between punctures mostly smaller than half as great as diameter of one puncture.

Prosternal sutures deeply grooved up to about 2/3 their length, then simply furrowed. Prosternal lobe broadly rounded, rather short, partially covering labium, laterally separated from rest of prosternum by obsolete transverse impression at about anterior 1/4 of prosternum, with distinctly carinate anterior margin. Prosternum lower than prosternal lobe at about its anterior 1/3 with other short, obsolete, transverse lateral impressions. Prosternal punctures coarse, dense, at basal 2/3 of prosternum notably larger than on pronotum; intervals between punctures smaller than half as great as diameter of one puncture; in anterior 1/3 of prosternum punctures smaller, intervals between punctures equal to or smaller than half as great as diameter of one puncture. Anterior and lateral parts of hypomeron with dense punctation, intervals between punctures on average smaller than diameter of one puncture; basal half of hypomeron near prosternal suture with larger and sparser punctation, intervals between punctures on average subequal to or greater than diameter of one puncture; intervals between punctures on hypomeron matt. Hypomeron with rather deep depression for insertion of profemora at base; this depression impunctate; hypomeron slightly impressed along prosternal suture in basal 1/2. Prosternal process with weak prominence near apex, about 3 times as long as diameter of procoxal cavity, slightly bent inwards immediately beyond procoxal cavities. Mesoventrite and metaventrite similarly punctate, intervals between punctures about half as great as diameter of one puncture, punctures subequal in size to those on anterior and lateral parts of hypomeron. Metaventrite about as long as wide (length/width 0.96), without depressions. Metepisternum slender, almost parallel-sided. Broad part of metacoxal plates about 4 times as wide as narrow part.

Scutellum short, slightly longer than wide, quadrangular, weakly convex, with punctation as on elytra. Elytra ellipsoidal, slightly wider than pronotum, widest near middle, more than twice as long as pronotum (length: 8.20 mm; width: 4.25 mm); tapering more strongly to apex than to base; shoulders obtusely rounded. Disc of elytra flat, faintly convex lateral of scutellum; elytra distinctly sloping at posterior 1/3; elytra flattened along external margin, slightly divergent along suture near apex, blunted at apex; without striae, more or less evenly punctate; punctures about same size as on head or smaller, rather sparse, intervals between punctures subequal to 1–4 diameters of one puncture.

Metathoracic wings reduced, reaching about middle of elytra.

Abdomen. Punctation of abdomen rather sparse, intervals between punctures subequal to or greater than diameter of one puncture; punctures slightly smaller than on metaventrite.

Female genitalia. (Figs. 4, 7). Ovipositor relatively long; baculum long, strongly sclerotized (ratio length baculum/length ovipositor 0.79); coxite moderately sclerotized, with several setae, narrowed to apex, with very small, almost indistinct stylus. Bursa copulatrix with typical large sclerotized plate covered with short spinules and long spines, distally with small sclerotized plate with short spinules; several dark sac-like spermatophores contained inside bursa copulatrix.

Male. Unknown.

Larva. Unknown.

Distribution. China: northwestern Yunnan province, the Hengduan Mountains.

Bionomics. This species was collected at the mid-altitude forest. The habitat of L. diqingensis sp. nov. is a mixed forest with conifers, open meadow areas, rhododendrons and partially with bamboo (I.I. Kabak, pers. comm.). Other aspects of the biology of this species remain unknown.

Etymology. From the type locality.

Figures

FIGURES 1 – 3. Habitus of Lacon species, dorsal view. 1. L. diqingensis sp. nov., female, holotype (13.2 mm). 2. L. lijiangensis sp. nov., female, holotype (9.5 mm). 3. L. salvazai, female (20.1 mm; China, Yunnan). Not to scale. FIGURES 4 – 6. Female genital tract of Lacon species, general view. 4. L. diqingensis sp. nov., holotype. 5. L. lijiangensis sp. nov., holotype. 6. L. salvazai (partially damaged; China, Yunnan). Not to scale.