Medhiama rhododendri Bordoni, 2007

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 : 183-185

6. Medhiama rhododendri Bordoni, 2007

( Fig. 8 A–K)

Bordoni, 2007a: 12 (Type locality: China, N Yunnan Diqing Tibet Aut. Pref., Deqin Co., Meili Xue Shan, E side, 14 km W Deqin, 2580 m, 28°27ˏN, 98°46ˏE); Bordoni, 2007b: 71 (catalog).

Material examined: male, with labels as follows: “ PARATYPUS, Medhiama , rhododendri sp. n., Bordoni det. 2005”/ “ CHIA: N-Yunnan [C 2005-16], ‘Nujiang Lisu Aut. Pref.,’ Gongshan Co., ‘Gaoligong Shan,’ sidevalley, ‘ 3000–3050 m,’ ‘27°47.90ʹN, 98°30.19ʹE’”/ “conif. forest with Rhododendron . broad, ‘leaved bushes, litter, moss,’ dead wood, sifted along creek and snowfields, 21.VI.2005, M. Schülke [C 2005-16]”; female, with labels as follows: “ PARATYPUS, Medhiama , rhododendri sp. n., Bordoni det. 2005”/ “ CHINA (N-Yunnan) Diqing Tibet. Aut., ‘Pref., Zhongdian Co.,’ 35 km ESE, ‘Zhong-dian,’ ‘ 3450 m,’ 27°41.00ʹN/, ‘100°01.47ʹE,’ (devastaded mixed forest, ‘near small creek, sifted from litter,’ moss, ‘dead wood),’ 3.VI.2005 D.W.Wrase [03]” (CS).

Description. Male. Measurement. BL= 6.75 mm, FL= 3.33 mm, HL= 1.08 mm, HW= 0.82 mm, PL= 1.14 mm, PW= 0.72 mm, EL= 0.97 mm, EW= 0.95 mm.

Body nearly cylindrical and medium sized. Entirely brown, except head darker in color.

Head. Not very elongate (HL to HW ratio 1.33), tempora slightly widened, posterior angles widely rounded. Dorsal integument entirely bearing mixed and shallow 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 bearing shallow 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 quite small and flat, diameter subequal to 1/5 of temporal length (eye: tempora = 0.15: 0.76 mm). Epistoma of medium width, subrectangular and flat, with a pair of tiny punctures. Distance between antennal insertions 0.22 mm, longer than distance from antenna to eye (0.19 mm).

Antennae. Scape stout, thickened apically, much longer than three subsequent antennomeres combined, 0.46 mm; antennomere II subglobular, 0.10 mm; III elongate, slightly shorter than II, 0.090 mm; IV and V subequal in length, 0.080 mm; last antennomere of medium length, 0.19 mm, subequal to two preceding antennomeres combined.

Mouthparts. Labrum bilobed and long, with a median longitudinal groove. Mandibles falciform, with two teeth on each inner edge ( Fig. 8 H). Maxillary palpus elongate, segment III longest, last segment slender and obconical and shorter than III ( Fig. 8 J). Labial palpus distinctly slender, last segment longest ( Fig. 8 K). Mentum subtrapezoid, with slightly emarginated anterior margin ( Fig. 8 I).

Neck. Medium width (0.32 mm), 2/5 of head width, with a transverse substraight ridge on anterior 1/3.

Pronotum. Subrectangular (PL to PW ratio 1.58), slightly longer but narrower than head. Widest at anterior 1/3, narrowest at posterior 1/3. Anterior angles widely rounded and not protruding, lateral margins slightly sinuate from middle, posterior angles rounded. Integument bearing shallow transverse microstriae, and a pair of admedian row of 12–14 punctures, smaller than those on head. Areas outside admedian rows with additional, irregular, sparsely set punctures.

Mesoscutellum. Shiny, extensively bearing shallow transverse microstriae and with a pair of tiny punctures near apex.

Elytra. Subquadrate (EL to EW ratio 1.02), slightly shorter 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 shiny, surface entirely covered with a distinct mixture of extensive microstriae and polygonal reticulum; punctures small, sparsely scattered, interspace between them 3–4 puncture diameters, but slightly denser on tergite VII. Each tergite with median longitudinal impunctate region width equals to 3–4 puncture diameters, without distinct basal impression near anterior margin. Surface between two basal transverse carinae of tergites III–VII bearing distinct polygonal reticulum ( Fig. 8 G). All abdominal sternites shiny, with transverse microstriae and setiferous punctures as those on tergites. Abdominal segment VIII entirely covered with setiferous punctures, posterior margins of tergite VIII subtruncated; that of sternite VIII widely arcuate ( Fig. 8 A, B). Tergite IX symmetrical, connected mediobasally. Sternite IX, with linearshaped base and rounded apex ( Fig. 8 D). Tergite X symmetrical and oblong, broadest near middle, base distinctly sharp ( Fig. 8 C). Aedeagus subspherical and medium sized ( Fig. 8 E, F), basal bulb 0.68 mm long. Parameres symmetrical and long, 0.42 mm and subequal to 3/5 of basal bulb length. Internal sac soft and brown, without sclerotized structures and elevated medially ( Fig. 8 E).

Female. Body larger, dark brown with yellowish elytra; head quite oblong; punctures on head much denser; eyes much bigger; antennomere II and III both elongate; punctures on Abdominal segments much denser.

Distribution. China (Yunnan).

Remarks. The male paratype (male from Gaoligong) has key morphological characters different from the holotype (male from Zhongdian) by checking the original description, e.g. more arcuate posterior margin of male sternite VIII, distinctly widened tergite X and much thinner parameres of aedeagus. These differences are usually used to distinguish different species. This male paratype also possesses key morphological characters dissimilar from the examined female paratype (see description of female). Bordoni (2007) did not mention those great differences between two paratype specimens, which were collected from different localities.

Figures

FIGURE 8. Medhiama rhododendri Bordoni: A. male tergite VIII; B. male sternite VIII; C. male tergite X; D. male sternite IX; E. aedeagus with everted inner sac, dorsal view; F. aedeagus, ventral view; G. male tergite V; H. mandibles; I. mentum; J. maxillary palpus; K. labial palpus. Scale bars 0.15 mm.