Exocelina varirata Shaverdo & Balke

Shaverdo, Helena, Sagata, Katayo & Balke, Michael, 2016, Taxonomic revision of New Guinea diving beetles of the Exocelinadanae group, with the description of ten new species (Coleoptera, Dytiscidae, Copelatinae), ZooKeys 619, pp. 45-102 : 72

Taxon classification Animalia Coleoptera Dytiscidae

13. Exocelina varirata Shaverdo & Balke sp. n. Figs 18, 34

Exocelina undescribed sp. MB3303: Toussaint et al. 2014: supplementary figs 1-4, tab. 2.

Type locality.

Papua New Guinea: National Capital District Province, Varirata National Park, 09°26.13'S; 147°22.09'E, 600 m a.s.l.

Type material.

Holotype: male "Papua New Guinea: National Capital District, Varirata NP, 600m, 16.xii.2007, 09.26.13S 147.22.09E, Balke & Sagata (PNG 159)", "DNA M.Balke 3303" [green] (ZSM). Paratype: Central: 1 male "Papua New Guinea: Central, Myola, 1110m, i.2008, 09 12.630S 147 31.880E, Posman (PNG 177)", "DNA M.Balke 3407" [green] (ZSM).

Diagnosis.

Beetle medium-sized, dark brown, with reddish-brown pronotal sides; dorsal surface with strong punctation and microreticulation, matt; pronotum with distinct lateral bead; male antennomeres simple; male protarsomere 4 with large, thick, strongly curved anterolateral hook-like seta; median lobe slender, with slightly curved, short, broad apex and compact area of fine distal setae in lateral view, with slightly concave apex in ventral view; paramere with very shallow notch on dorsal side. The species is very similar to Exocelina wareaga sp. n. but differs from it in shape of the median lobe: it is more slender, lateral margins apically and subapically not very thick and not bordered with a carina; also the fine distal setae on lateral sides of the median lobe are not situated linearly, but in compact areas.

Description.

Size and shape: Beetle medium-sized (TL-H 4.25-4.35 mm, TL 4.5-4.85 mm, MW 2.25-2.45 mm), with oblong-oval habitus, broadest at elytral middle. Coloration: Head reddish brown to dark brown, paler on clypeus; pronotum dark brown on disc and reddish-brown on sides; elytra uniformly dark brown; ventrally dark brown; head appendages reddish-brown, legs darker distally (Fig. 34).

Surface sculpture: as in Exocelina wareaga sp. n.

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

Male: Antenna simple. Protarsomere 4 with large, thick, strongly curved anterolateral hook-like seta. Protarsomere 5 ventrally with anterior band of more than 70 short setae and posterior row of 12 relatively long, thin setae (Fig. 18A). Abdominal ventrite 6 with 4-6 lateral striae on each side. Median lobe slender, with slightly curved, short, broad apex and compact area of fine distal setae in lateral view, with slightly concave apex in ventral view (Figs 18 B–C). Paramere with very shallow notch on dorsal side, with thin, sparse, inconspicuous proximal setae and thicker, denser, and longer subdistal setae (Fig. 18D).

Holotype: TL-H 4.35 mm, TL 4.85 mm, MW 2.45 mm.

Female: Unknown.

Distribution.

Papua New Guinea: National Capital District and Central Provinces (Fig. 40).

Etymology.

The species is named after Varirata National Park. The name is a noun in the nominative singular standing in apposition.