Platambus korgei, Hendrich, Lars & Przewoźny, Marek, 2015

Hendrich, Lars & Przewoźny, Marek, 2015, Two new species of the genus Platambus Thomson, 1859 from China (Coleoptera: Dytiscidae, Agabinae), Zootaxa 3947 (2), pp. 191-200 : 193-196

Platambus korgei sp. n.

( Figs 8 , 10 , 16 )

Type locality. China, Sichuan Province, Wolong Nature Reserve, ca. 150 km NW Chengdu, ca. 31° 01'N 103°10'E

Type material. Holotype, male: “ China /Central China Sichuan Prov., Wolong [Nature Reserve] 150 km NW Chengdu [ca. 31°01'N 103°10'E, ca. 2000 m], 9.-10.VII.1994, V. Beneš leg.”, “ Holotype Platambus korgei sp. n. Hendrich & Przewoźny des. 2014” [red printed label] ( NMW). Paratype: Male, with same data as holotype and provided with red printed paratype label ( CLH).

Diagnosis. Medium sized Platambus with elongate, oval and slightly convex body. Dorsal surface completely black as depicted in Fig. 8 .

Description. Measurements: Holotype: Total body length 8.4 mm, body length without head 7.5 mm, width 4.3 mm. Paratype: Total body length 7.8 mm, body length without head 6.9 mm, width 4.0 mm.

Head almost completely black with two paler spots basally, appendages reddish. Reticulation consisting of well impressed polygonal meshes, irregular in size, with several very small punctures within them, and larger punctures at intersections of all meshes. Large punctures compose row alongside eyes, and distinct fronto-clypeal fovea.

Pronotum slightly cordiform, broadest in middle. Lateral margin rounded in anterior half, weekly sinuated before posteriors angles. Posterior angles rectangular. Pronoto-elytral angle distinct. Coloration black. Reticulation similar to that on head. Anterior margin with row of large setigerous punctures, similar row near posterior margin, broadly interrupted at middle. Lateral margin broadly and distinctly bordered.

Elytron totally black ( Fig. 8 ). Epipleura ferruginous. Reticulation consisting of distinctly impressed polygonal meshes, with several minute punctures within them, and larger punctures at intersections of almost all polygonal meshes. Each elytron with sutural, discal and lateral rows of large serial setigerous punctures. Irregularly, densely and coarsely punctured between discal and lateral rows on posterior half of elytron.

Ventral side completely ferrugineous. Reticulation consisting of small polygonal meshes. Prosternal process elongate, lanceolate, bordered laterally and produced into long sharp point. Mesofemora and mesotibia ventrally with numerous large setigerous punctures. Metasternal wings narrow. Metacoxa with large punctures and irregular groves laterally. Metatrochanter rounded at apex. Metafemora without setae or large punctures near posterolateral angle. Metatibia ventrally with two longitudinal rows of large punctures. Ventrites with oblique groves, anal ventrite posteriorly with transverse corrugations and dense smaller punctures.

Male. Tarsomeres 1 – 3 of fore and middle legs broadly dilated with bristles on ventral side. Median lobe, in lateral view narrowing toward apex, slightly sinuous in apical third, tip slightly bent and rounded ( Fig. 10 a), in ventral view as in Fig. 10 b.

Female. Unknown.

Etymology. The new species is dedicated to the late Prof. Horst Korge (1930 – 2014, Berlin), entomologist, conservationist and specialist for Carabidae and Staphylinidae , for his outstanding efforts in inspiring young people in Berlin to study beetles. The specific epithet is a substantive in the genitive case.

Affinities. Platambus korgei sp. n. is habitually very similar to P. brancuccii sp. n. and P. wewalkai but can be recognized from P. brancuccii sp. n. by the less cordiform pronotum with posterior angles not prominent, and the black elytron; from P. wewalkai by a more oblong body and larger punctures at almost each intersection of elytral meshes. From both it can be separated by the presence of irregular, dense and coarse punctation between discal and lateral rows on posterior half of elytron, and the different shape of male median lobe.

Habitat. Nothing is known about the life habitat of the species. Probably a lotic species living in small mountain streams.

Distribution. So far known only from the type locality Wolong Nature Reserve in Sichuan, Central China ( Fig. 16 ).

Figures

FIGURE 16. Distribution of the Platambus semenowi- group in Central Asia, the Himalaya region and China.

FIGURES 5 – 8. Habitus of Platambus brancuccii sp. n., male (holotype) (5), male (paratype) (6), female (paratype) (7), P. korgei sp. n., male (paratype) (8). Scale bar 4 mm. Photos: Marek Przewoźny.

FIGURES 9 – 10. Aedeagus in lateral (a) and ventral view (b) of: Platambus brancuccii sp. n. (9 a / b) and P. korgei sp. n. (10 a / b). Scale bar 0.5 mm.