Medhiama sichuanica Bordoni, 2003

Zhou, Yu-Lingzi & Zhou, Hong-Zhang, 2012, Taxonomy of the genus Medhiama Bordoni, 2002 (Coleoptera: Staphylinidae, Staphylininae, Xantholinini) with descriptions of three new species, Zootaxa 3478, pp. 169-191: 186-187

publication ID 10.5281/zenodo.282239

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Medhiama sichuanica Bordoni, 2003


7. Medhiama sichuanica Bordoni, 2003 

Bordoni, 2003 b: 270 (Type locality: China, W-Sichuan, Daxue Shan, Paoma Shan, b. Kangding; 2700–2900 m, 30.02 56 N, 101. 58.05 E); Bordoni, 2004: 118 (Sichuan Hailuogou; Shaanxi, Qiling Shan, Houzhenzi); Bordoni, 2007 b: 71 (catalog); Bordoni, 2009: 238 ( China, Yunnan, Diancang Shan).

Material examined: male, with labels as follows: “ HOLOTYPUS, Medhiama  , sichuanica  sp. n., Bordoni det. 1997 ”/ “Sammlung, M. Schülke, Berlin”/ “ CHINA: W-Sichuan (6), ‘Daxue Shan,’ Paoma-Shan, ‘b. Kangding,’ 30.02.56 N, ‘101.58.05E,’ 2700–2900 m, ‘ 22.05.1997,’ M. Schülke” (CS).

Description. Measurement. BL= 9.80 mm, FL= 5.05 mm, HL= 1.55 mm, HW= 1.13 mm, PL= 1.63 mm, PW=1.00 mm, EL= 1.68 mm, EW= 1.58 mm.

Body nearly cylindrical and large sized. Entirely dark brown.

Head. Subrectangular (HL to HW ratio 1.38), tempora straight and slightly widened, posterior angles widely rounded. Dorsal integument entirely bearing mixed and distinct microsculpture composed of isodiametric microsculpture and transverse microstriae, and distributed deep and medium sized punctures, puncture intervals less than puncture diameter. Median longitudinal region impunctate, width equals to 2–3 puncture diameters; frontal region wrinkled basally and entirely bearing transverse microstriae, and 3 pairs of tiny punctures. Each side of cranium with anterolateral puncture near antennal insertion, midlateral puncture not very far from dorsal margin of eye (3–4 puncture diameters to eye), temporal puncture rather near lateral margin (at lateral 1 / 6) and occipital puncture rather near posterior margin (at posterior 1 / 6). Frontal furrows deep and long, convergent backwards; anteocular furrows indistinct, scarcely observable. Eye medium sized and flat, diameter subequal to 1 / 4 of temporal length (eye: tempora = 0.28: 1.13 mm). Epistoma not elevated, flat, with a pair of tiny punctures. Distance between antennal insertions 0.40 mm, longer than distance from antenna to eye (0.28 mm).

Antennae. Scape stout, thickened apically, much longer than three subsequent antennomeres combined, 0.63 mm; antennomere II elongate, 0.19 mm; III elongate, slightly shorter than II, 0.20 mm; IV and V subequal in length, 0.13 mm; last antennomere of medium length, 0.28 mm, slightly longer than that of two preceding antennomeres combined.

Mouthparts. Labrum bilobed and small, with a median longitudinal groove. Maxillary palpus elongate, segment III longest, last segment slender and obconical and shorter than III. Labial palpus distinctly slender, last segment longest.

Neck. Medium width (0.38 mm), 1 / 3 of head width, with a transverse substraight ridge on anterior 1 / 3.

Pronotum. Subrectangular and relatively long (PL to PW ratio 1.63), slightly longer but narrower than head. Anterior angles widely rounded and not protruding, lateral margins substraight, posterior angles rounded. Integument bearing distinct transverse microstriae, and a pair of admedian row of 12–14 punctures, smaller than those on head. Other irregular punctures relatively densely presenting outside of admedian row.

Mesoscutellum. Shiny, extensively bearing distinctly polygonal reticulum and with a pair of tiny punctures near apex.

Elytra. Subrectangular (EL to EW ratio 1.06), slightly longer but distinctly wider than pronotum. Humeri well developed, lateral margins widened posteriorly, hind margin rounded. Integument shiny, without microsculpture; each side symmetrically with regular rows of punctures, interspaces between rows 1–2 puncture diameters; deflexed portion of each elytron with 3–4 rows of punctures.

Legs. First four segments stout but not dilated in protarsi and metatarsi, whereas relatively slender in mesotarsi; each last segment as long as the II –IV combined. Protibia with apical ctenidium and subapical ctenidia, meso- and metatibia only with apical ctenidium.

Abdomen. Cylindrical, broadest at segment VII. Tergites III –VII opaque, surface entirely with polygonal reticulum, much denser basally; punctures small and rather dense, interspace between them 2–3 puncture diameters, but denser on tergite VII. Each tergite without distinct basal impression near anterior margin. Surface between two basal transverse carinae of tergites III –VII bearing distinct polygonal reticulum. All abdominal sternites shiny, with transverse microstriae and setiferous punctures as those on tergites.

Distribution. China (Yunnan, Sichuan, Shaanxi).

Remarks. This species can be easily distinguished from its congeners by the following characters: large body size, substraight lateral margin of pronotum, sternite IX, tergite X and aedeagus.