Exocelina pui, Shaverdo, Helena, Wild, Michael, Sumoked, Bob & Balke, Michael, 2017

Shaverdo, Helena, Wild, Michael, Sumoked, Bob & Balke, Michael, 2017, Six new species of the genus Exocelina Broun, 1886 from Wano Land, New Guinea (Coleoptera, Dytiscidae, Copelatinae), ZooKeys 665, pp. 93-120 : 98-99

6. Exocelina pui sp. n. Figs 8, 16

Type locality.

Papua: Puncak Regency, Puluk area, 03°35'56.1"S; 137°27'53.7"E.

Type material.

Holotype: male "Indonesia: Papua, Wano Land, red clay creek nr cave, 1100m, 3.ix.2014, nr -3.587955 137.5114945, Balke & Wild (Pap024)", "M.Balke 6518" [green text] (MZB). Paratypes: 5 males with the same label as the holotype, one of them with an additional label "M.Balke 6519" [green text] (ZSM).

Diagnosis.

Beetle small, dark brown to piceous, with paler anterior part of head and sides of pronotum, dorsal punctation fine, microreticulation distinctly impressed; pronotum without lateral bead; male antennae simple; male protarsomere 4 cylindrical, narrow, with large, thick, strongly curved anterolateral hook-like seta; median lobe slightly curved, with truncate apex in lateral view and abruptly narrowed apically, with apex concave in ventral view, having short, thick subdistal setae laterally; paramere without dorsal notch, with subdistal setae dense, strong, long and proximal setae very sparse, thin, small, weakly visible.

In habitus shape, coloration, and absence of the pronotal bead, E. pui sp. n. strongly resembles the small species from the E. ekari -group (one of them is its co-occurring species) but it distinctly differs from them in having different shape of the median lobe and paramere. The shape of the median lobe is very similar to that of E. rivulus (Balke, 1998), also a co-occurring species, from which E. pui sp. n. can be easily distinguished in its smaller size and absence of the pronotal bead. From E. likui sp. n., it differs in distinctly finer dorsal punctation and in having median lobe truncate in lateral view, with lateral setae.

Description.

Size and shape: Beetle small (TL-H 3.35-3.6 mm, TL 3.95-4.0 mm, MW 1.95-2.0 mm), with oblong habitus, broadest at elytral middle. Coloration: Head dark brown, almost piceous posteriorly and reddish brown anteriorly. Pronotum and elytra dark brown to piceous, pronotal sides reddish brown; head appendages and legs reddish brown (Fig. 8).

Surface sculpture: Head with fine and relatively dense punctation (spaces between punctures 1-3 times size of punctures), finer and sparser anteriorly; diameter of punctures almost equal to diameter of cells of microreticulation. Pronotum with sparser and finer punctation than head. Elytra with very sparse and fine punctation, often inconspicuous. Pronotum and elytra with distinctly impressed microreticulation, dorsal surface less shiny. Head with microreticulation stronger. Metaventrite and metacoxae distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles. Abdominal ventrites with distinct microreticulation, strioles, and very fine and sparse punctation.

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

Male: Antenna simple (Fig. 8). Pro- and mesotarsomeres 1-3 not dilated. Protarsomere 4 cylindrical, narrow, with large, thick, strongly curved anterolateral hook-like seta. Protarsomere 5 slightly concave ventrally, with anterior band of more than 40 and posterior row of 15 relatively long, not pointed setae (Fig. 16D). Median lobe slightly curved, with truncate apex in lateral view and abruptly narrowed apically, with apex concave in ventral view, having short, thick subdistal setae laterally. Paramere without dorsal notch, with subdistal setae dense, strong, long and proximal setae very sparse, thin, small, weakly visible (Fig. 16 A–C). Abdominal ventrite 6 broadly rounded apically, with 6-8 fine transverse lateral strioles on each side.

Holotype: TL-H 3.6 mm, TL 4.0 mm, MW 2.0 mm.

Female: Pro- and mesotarsi not modified. Abdominal ventrite 6 without lateral strioles.

Distribution.

Papua: Puncak Regency. The species is known only from the type locality (Fig. 19).

Etymology.

The species is named after a young Wano man Pu, who grew up in Puluk and accompanied his father (now deceased) on many hunting trips in the area where this species was collected. The name is a noun in the genitive case.