Lamiogethes limaelytralis, Liu & Yang & Huang & Cline & Sabatelli & Audisio, 2020

Liu, Meike, Yang, Xingke, Huang, Min, Cline, Andrew Richard, Sabatelli, Simone & Audisio, Paolo, 2020, Five new species of Lamiogethes Audisio & Cline from China (Coleoptera Nitidulidae: Meligethinae), Zootaxa 4728 (1), pp. 63-76 : 73-74

Lamiogethes limaelytralis sp. n.

( Figs. 1e , 2 i–j, 3h, 5)

Diagnosis. Vaguely similar in external body shape and color to small specimens of the common Palearctic species L. brunnicornis (in the L. difficilis species group: Audisio 1993). Male metatibiae rather normally shaped, not sinuate along inner edge ( Fig. 1e ) and rather rectilinear along most of outer edge. Male genitalia distinctively shaped, with elongate, deeply and narrowly incised tegmen ( Fig. 2i ), aedeagal median lobe moderately large, ca. 2.1× longer than wide, maximum width at distal two-thirds, and with simple, ogive-shaped distal apex ( Fig. 2j ).

Description. Size (male holotype): body length 2.60 mm, width 1.55 mm.

Body color and pubescence: uniformly dark brown, tegument shiny. Legs brown to dark brown, with slightly paler tarsal plates and protibiae, antennae uniformly reddish-brown. Pubescence golden, rather long and sparse, not concealing tegument, each individual seta ca. 0.90× as long as second antennomere ( Fig. 1e ).

Dorsal habitus: body shape ( Fig. 1e ) vaguely similar to the common European species L. brunnicornis . Clypeus with slightly arcuately sinuate anterior margin. Dorsal punctures on pronotum fine and deep, each puncture separated from another by ca. 1.2–1.6 diameter; space between punctures smooth and shining. Dorsal punctures on elytra large, separated by ca. 1.2–1.5 diameter; space between punctures smooth and shining. Ratio LPR1/LELY = 0.48; ratio WPR1/LPR1 = 1.97; ratio WPR2/LPR1 = 1.85; ratio WPR2/WPR1 = 0.94; ratio LELY/WELY = 0.95; ratio WPR1/WPRA = 1.69; ratio WPR1/WELY = 0.90; ratio WPR2/WELY = 0.85.

Ventral habitus: combined outer edges of antennal grooves almost straight, parallel-sided along most of length. Prosternal process wide, nearly as 1.5× as wide as antennal club, with coarse and close punctation. Male metaventrite markedly and widely impressed, with a rather deep semi-circular transverse impression, occupying posterior half, and two distinctly raised elongate longitudinal tubercles, nearly as long as second antennomere, situated on each side of impression, prior to middle portion. Last visible ventrite appearing simple, without distinct shining tubercle in middle of posterior edge.

Appendages: antennae rather short ( Fig. 1e ); ratio ANLE/HWEA = 0.71; ratio CLLE/W10J = 1.30; ratio L03J/ W03J = 2.6; ratio L03J/L02J = 0.90; ratio L03J/L04J = 2.0; ratio WFTA/LFTA ≈ 0.33; ratio LETI/WITI ≈ 3.40. Protibiae with a series of 3–5 moderately sharp teeth, increasing in size from first to penultimate, shaped nearly as in the S European and Anatolian species L. bucciarellii Audisio, 1976 ( Fig. 3h ). Metatibiae simple, not arcuately curved or sinuate along inner side ( Fig. 1e ).

Male genitalia: distinctively shaped, with elongate tegmen ( Fig. 2i ), widest in middle, medial distal excision moderately deep and narrowly U-shaped (ratio DTIN/LETE ≈ 0.27), inner margins of excision simple, without pro- jection; ratio LETE/WITE ≈ 1.73. Median lobe of aedeagus rather large and long (ratio LEAE/WIAE ≈ 2.1; Fig. 2j ), exhibiting maximum width nearly at distal two-thirds, with narrowed, ogive-shaped distal apex and slightly concave proximal apex.

Female: unknown.

Variation: body size 2.50–2.60 mm (length) and 1.50–1.55 mm (width).

Examined material. Holotype, ♂: China: Sichuan, Xiangcheng Co., above Xiangcheng , 3100–3400 m a.s.l., 28°35'24"N 99°33'0"E, 19.vi.2017, Liu & Audisio ( NWAU) . Paratype: same data as holotype, 1 ♂ ( CAR-MZUR) .

Distribution. SW China (Sichuan) ( Fig. 5 ).

Host-plants. Unknown, but probably among Lamiaceae . The two males included in the type material were collected intermixed among numerous specimens of L. convexistrigosus Liu, Huang, Cline & Audisio, 2017 and a few L. forcipenis Liu, Huang, Cline & Audisio, 2017 ; both species may be associated with Phlomoides umbrosa (Lamiaceae) ( Liu et al. 2017).

Habitat. Locality data indicate this species prefers the edges of high altitude, forested and bushy areas.

Phenology. The two available specimens were collected in middle June, which likely indicates adult activity at least from May to July.

Etymology. The specific epithet is derived from the Latin lima (= file), due to its peculiarly strong and rather uniformly transversely strigose elytra ( Fig. 1e ), similar to the condition typical of some members of the genus Astylogethes Kirejtshuk, 1979 , which are not closely related.

Taxonomic remarks. As reported above, this new species is vaguely similar in external body shape to L. brunnicornis from Europe (see Audisio 1993), as well as to other E Palearctic species of the genus, but is almost certainly more closely related to L. forcipenis from Sichuan and allied species ( Liu et al. 2017). However, male specimens of the latter species exhibit a markedly different tegmen and median lobe of the aedeagus. Possible phylogenetic relationships of L. limaelytralis sp. n. with L. ancestor and allied species described above need further analyses.

Figures

FIGURE 1. Habitus of Lamiogethes spp.: a, L. falcatus sp. n. male from China, Sichuan; b, L. hastipenis sp. n., male from China, Hubei; c, L. sagittalis sp. n., male from China, Shaanxi; d, L. unditibiis sp. n., male from China, Chongqing; e, L. limaelytralis sp. n., male from China, Sichuan. Scale bar: 0.5 mm (Figs. a–e).

FIGURE 2. Male genitalia (tegmen and median lobe of aedeagus, dorsal view) of Lamiogethes spp.: a–b, L. falcatus sp. n., male from China, Sichuan; c–d, L. hastipenis sp. n., male from China, Hubei; e–f, L. sagittalis sp. n., male from China, Shaanxi; g–h, L. unditibiis sp. n., male from China, Chongqing; i–j, L. limaelytralis sp. n., male from China, Sichuan. Scale bar: 0.2 mm (Figs. a–j).

FIGURE 3. Female genitalia (ovipositor, ventral view) of Lamiogethes spp. (a–c): a, L. falcatus sp. n. from China, Sichuan (female not selected as paratype); b, L. sagittalis sp. n., female from China, Shaanxi; c, L. unditibiis sp. n., female from China, Chongqing. Protibiae of Lamiogethes spp. (d–h): d, L. falcatus sp. n., male from China, Sichuan; e, L. hastipenis sp. n., male from China, Hubei; f, L. sagittalis sp. n., male from China, Shaanxi; g, L. unditibiis sp. n., male from China, Chongqing; h, L. limaelytralis sp. n., male from China, Sichuan. Metatibiae of Lamiogethes spp. (i–j): i, L. falcatus sp. n., male from China, Sichuan; j, L. unditibiis sp. n., male from China, Chongqing. Scale bar: 0.2 mm (Figs. a–j).

FIGURE 5. Distribution map of Chinese Lamiogethes treated herein.