Megalinus zhenyuanensis ( Zheng, 1994 )

ZHOU, YU-LINGZI, BORDONI, ARNALDO & ZHOU, HONG-ZHANG, 2013, Taxonomy of the genus Megalinus Mulsant & Rey (Coleoptera: Staphylinidae, Xantholinini) and seven new species from China, Zootaxa 3727 (1), pp. 1-66 : 59-63

Megalinus zhenyuanensis ( Zheng, 1994)

(Fig. 17A–C; Fig. 17-1A–F; Fig. 17-2A–F)

Zheng, 1994: 349, 352 ( Lepidophallus ; Type locality: China: Gansu, Shenyuan County); Herman, 2001a: 3662 (catalog); Smetana, 2004: 689 (catalog); Bordoni, 2004: 117 ( China, Gansu, Lanzhou); Bordoni, 2008: 58 ( Megalinus ; species list of Megalinus ); Bordoni, 2009b: 108 (Qinghai)..

Type materials: female, with labels as follows: “ Allotype, Lepidophallus zhenyuanensis sp. nov. det. Zheng ” / “ 1985.V.23, leg. Cao Wei ” / “ Gansu, Zhenyuan, Baima”; male, with labels as follows: “ Lepidophallus zhenyuanensis Zheng ” / “ 1995.VII.22, leg. Zhen ” / “ Gansu, Lanzhou”; male, with labels as follows: “ Lepidophallus zhenyuanensis Zheng ” / “Qinghaishida, 1995.VIII.7, leg. Ji Tian-30” ( CZ) .

Additional material: China: Qinghai, Qilian , one male, 2560 m, 10.VIII.1957, Zhang Yiran collected ( IZ- CAS) .

Description.

Measurements. BL= 8.8 mm, FL= 5.1 mm, HL= 1.5 mm, HW= 1.3 mm, PL= 1.8 mm, PW= 1.2 mm, EL=1.6

mm, EW= 1.5 mm. broadly rounded. Dorsal integument shiny, without microsculpture, but densely distributed with round, mediumsized punctures, interspaces between punctures 2–3 punctures’ diameter, except a impunctate longitudinal median band of width ca. 0.2 mm. Each side of cranium also with frontal puncture on epistoma, anterolateral puncture near antennal insertion, 3–4 small punctures on frontal region, midlateral puncture approximately a distance of 4–5 punctures’ diameter from dorsal margin of eye, temporal puncture at posterior 1/5, and occipital puncture at lateral 1/3; deflexed portion of head bearing 2–3 rows of small punctures. Frontal furrows convergent, as long as anteocular furrows. Anteocular furrows wider than frontal furrows, nearly arriving line connecting posterior 1/5 of each eye. Eye median sized, equal to 1/3 of temporal length (eye: temple = 0.33: 0.93 mm), protruding laterad. Epistoma protruding forwards, of subrectangular shape, anterior margin subtruncated. Distance between antennal insertions 0.30 mm, slightly longer than that from antenna to eye (0.28 mm).

Antennae. Scape stout, thickened apically, longer than three subsequent antennomeres combined, 0.70 mm; antennomeres II and III both elongate and of same length, ca. 0.18 mm; IV and V transverse, subequal in length, 0.08 mm; last antennomere of medium length, 0.23 mm, slightly shorter than length of preceding two antennomeres combined.

Neck. Medium width (0.50 mm), slightly wider than 1/3 of head width.

Pronotum (Fig. 17A). Subrectangular, distinctly elongated (PL to PW ratio 1.4), longer than head, but slightly narrower. Anterior angles well-developed and protruding, lateral margins sinuate, posterior angles broadly rounded. Integument shiny, two rows of setiferous punctures presenting on each side, admedian row consisting of 9–10 punctures; lateral row, curvedly arranged, of 12–14 punctures; other irregular punctures scattered near anterior margin.

Mesoscutellum. Shiny, extensively covered with microstriae mixed with longitudinal microwaves on apical 1/ 3, and with a pair of punctures at apical 1/3.

Elytra (Fig. 17A). Subquadrate (EL to EW ratio 1.1), of same length to pronotum, but distinctly wider. Humeri well developed, lateral margins widened posteriorly, hind margin arcuate backwards. Integument shiny and flattened, without microsculpture; each elytron with 7–8 rows of punctures, which smaller than those on head and pronotum; deflexed portion with 3–4 rows of smaller punctures.

Abdomen. Cylindrical, broadest at segment VI. Tergites III–VII shiny, covered with obviously transverse microstriae, and also bearing small setiferous punctures, interspaces between punctures near 2–3 punctures’ diameter, denser laterobasally; each segment with a impunctate basal impression, which bearing transverse

Male (SM. Fig. 1). Median lobe of aedeagus subelliptical, basal piece without transparent, membranous medial-longitudinal band, anterior portion cylindrical. Parameres symmetrical, long, slightly shorter than 1/2 of basal bulb length. Internal sac S-shaped, dark colored.

Female. Unknown.

Distribution. China (Gansu, Qinghai).

Remarks. This species could be distinguished from its congeners by: 1) head subquadrate with dilated temples; 2) the impunctate longitudinal median band of the width ca. 0.2 mm; 3) admedian row consisting of 9–10 punctures; lateral row, curvedly arranged, of 12–14 punctures; 4) mesoscutellum extensively covered with microstriae mixed with longitudinal microwaves on apical 1/3; 5) inner sac morphology. However, the specimen from Lanzhou (Gansu) possesses the following variants: body dark with reddish abdomen; antennae brown with basal three dark; temple more dilated; eye flattened; anteocular furrow shallow; the impunctate longitudinal median band ca. 0.25 mm; interspaces between punctures on head ca. one puncture diameter; anterior angle of pronotum more rounded and protruding; admedian row of pronotum of 11–12 punctures; mesoscutellum smaller, the following changes: body brown; head ovoid, temple more rounded, broadest near middle of head; anteocular furrows shallow; eye small and flattened; the impunctate longitudinal median band with the width more than 0.25 mm; pronotum broader; anterior angles of pronotum more rounded; admedian row of 11–12; puncture on abdomen more uniformly distributed (Fig. 17-2A–F). Due to the few study material we had, these questions we pointed out should be solved until more specimens are gathered.

Supplimentary material:

FIGURE 1. Dorsal view of median lobe of aedeagus of holotype of M. zhenyuanensis (Zheng) (Photoed by Prof. Fake Zheng).