Exocelina ksionseki Shaverdo & Balke

Shaverdo, Helena, Sagata, Katayo, Panjaitan, Rawati, Menufandu, Herlina & Balke, Michael, 2014, Description of 23 new species of the Exocelinaekari-group from New Guinea, with a key to all representatives of the species group (Coleoptera, Dytiscidae, Copelatinae), ZooKeys 468, pp. 1-83 : 13

Taxon classification Animalia Coleoptera Dytiscidae

8. Exocelina ksionseki Shaverdo & Balke sp. n. Figs 18, 46

Type locality.

Papua New Guinea: Madang Province, Adalbert Mts., near Keki, 04°43.06'S; 145°24.44'E.

Type material.

Holotype: male "Papua New Guinea: Madang, Keki, Adalbert Mts, 400m, 29.xi.2006, 04.43.058S 145.24.437E, Binatang Boys, (PNG 119)" (ZSM). Paratypes: Madang: 1 male with the same label as the holotype (NHMW). Western Highlands: 2 males, 1 female "Papua New Guinea: Western Highlands, Kurumul, 6Km SW Kudjip, small stream, 1580m, 13.vi.2006, 05.53.426S 144.36.600E, John (PNG 78)" (ZSM). 4 males, 2 females "Papua New Guinea: Western Highlands, Mt. Hagen town area, 1600m, 7.xii.2006 05.49.745S 144.22.357E Balke & Kinibel (PNG 131)" (NHMW, ZSM).

Diagnosis.

Beetle medium-sized, piceous, with reddish sides of pronotum and sometimes with reddish head, submatt; pronotum with lateral bead; male antennomere 3 evidently larger than other antennomeres; male protarsomere 4 with very small (only slightly larger than more laterally situated large seta), thin, slightly curved anterolateral hook-like seta; median lobe with very weak submedian constriction, apex of median lobe elongate in lateral view; paramere distinctly longer than median lobe, without notch on dorsal side, with relatively long and dense subdistal setae and numerous spine-like setae on internal surface, proximal setae almost absent. The species is similar to Exocelina knoepfchen Shaverdo, Hendrich & Balke, 2012 except for evidently smaller size, coarse, dense dorsal punctation, beetle submatt, male antennomeres 3 larger, with more rounded external margin, male protarsomere 4 with anterolateral hook-like seta larger than more laterally situated large seta, narrow apical half (in ventral view) of median lobe, with elongate apex in lateral view, and setation of paramere. It differs from Exocelina kisli sp. n., see under Exocelina kisli sp. n.

Description.

Size and shape: Beetle medium-sized (TL-H 3.8-4.2 mm, TL 4.2-4.6 mm, MW 2-2.3 mm), with elongate habitus, broadest at elytral middle. Coloration: Head reddish to piceous with reddish clypeus; pronotum piceous, with reddish sides; elytra uniformly piceous or with reddish brown sutural lines; head appendages yellowish or reddish, legs usually darker distally (Fig. 46). Teneral specimens paler.

Surface sculpture: Head with very dense, coarse punctation (spaces between punctures 1-2 times size of punctures), finer and sparser anteriorly; diameter of punctures only slightly smaller than diameter of cells of microreticulation, of some punctures equal to it. Pronotum and elytra with slightly finer and more evenly distributed punctation than on head. Pronotum and elytra with more weakly impressed microreticulation than on head. Dorsal surface submatt due to strong punctation. Metaventrite and metacoxa distinctly microreticulate, metacoxal figs with longitudinal strioles and transverse wrinkles. Abdominal ventrites with distinct microreticulation, strioles, and fine sparse punctation, coarser and denser on two last abdominal ventrites.

Structures: Pronotum with lateral bead. Base of prosternum and neck of prosternal process with distinct ridge, smooth and rounded anteriorly, without anterolateral extensions. Blade of prosternal process lanceolate, relatively narrow, convex, with distinct lateral bead and few setae; neck and blade of prosternal process evenly jointed. Abdominal ventrite 6 broadly rounded apically.

Male: Antennomere 2 very small, stout, antennomere 3 strongly enlarged, evidently larger than other antennomeres, with rounded external margin, antennomeres 4-6 distinctly enlarged, antennomere 7 slightly enlarged (Fig. 18A). Protarsomere 4 with very small (only slightly larger than laterally situated large seta), thin, slightly curved anterolateral hook-like seta. Protarsomere 5 ventrally with anterior row (double apically) of 14 short setae and posterior row of 4 short setae (Fig. 18B). Abdominal ventrite 6 with 14-17 lateral striae on each side. Median lobe narrow in apical half and broad in basal one, with weak submedian constriction in ventral view and elongate apex in lateral view (Fig. 18C, D). Paramere distinctly longer than median lobe, without notch on dorsal side, with relatively long and dense subdistal setae and numerous spine-like setae on internal surface (Fig. 18E).

Holotype: TL-H 4.1 mm, TL 4.5 mm, MW 2.15 mm.

Female: Antennomere 1 as in male or only slightly larger, other antennomeres simple, abdominal ventrite 6 broadly rounded apically, without striae.

Distribution.

Papua New Guinea: Madang and Western Highlands Provinces (Fig. 53).

Etymology.

The species is named for K. Ksionsek. The species name is a noun in the genitive case.