Exocelina injiensis 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 : 66

Taxon classification Animalia Coleoptera Dytiscidae

9. Exocelina injiensis Shaverdo & Balke sp. n. Figs 8, 30

Exocelina undescribed sp. MB1376: Toussaint et al. 2014: supplementary figs 1-4, tab. 2.

Type locality.

Papua New Guinea: Morobe Province, Menyamya, Inji Mountain, 07°14.26'S; 146°01.40'E, 1500 m a.s.l.

Type material.Holotype: male "Papua New Guinea: Morobe, Menyamya, Mt Inji, deep well, 1500m, 14.xi.2006, 07.14.264S 146.01.400E, Balke & Kinibel (PNG 98)" (ZSM). Paratypes: 22 males, 29 females with the same label as the holotype, one male additionally with a green label "DNA M.Balke 1376" (NHMW, ZSM).

Diagnosis.

Beetle small; piceous, with reddish brown to brown head and pronotum laterally; matt, with strong punctation and microreticulation; male antennae simple; male protarsomere 4 with large, thick, strongly curved anterolateral hook-like seta; median lobe with slightly curved, rounded apex in lateral view and with almost truncate apex in ventral view, on both lateral sides with strong, short setae situated almost linearly on anterior half of distal part of median lobe under fine carina; paramere without notch on dorsal side. The species is very similar to Exocelina andakombensis sp. n. but differs from it in presence of the lateral carina, bordering shorter distal setae, on the median lobe and the large, thick, strongly curved anterolateral hook-like seta of protarsomere 4, as well as longer and much numerous ventral setae of protarsomere 5, see also under diagnosis of Exocelina andakombensis sp. n.

Description.

Size and shape: Beetle small (TL-H 3.05-3.55 mm, TL 3.4-3.85 mm, MW 1.6-1.9 mm), with oblong-oval habitus, broadest at elytral middle. Coloration: Head reddish brown to dark brown, with small darker areas posterior to eyes; pronotum reddish brown to dark brown, paler laterally, often piceous on disc; elytra piceous, dark brown laterally, with narrow reddish sutural lines; head appendages and legs proximally yellowish red, legs distally darker, reddish brown, especially metathoracic legs (Fig. 30). Teneral specimens paler.

Surface sculpture: as in Exocelina andakombensis sp. n.

Structures: Pronotum with distinct lateral bead. Base of prosternum and neck of prosternal process with distinct ridge, slightly rounded anteriorly. Blade of prosternal process lanceolate, relatively broad, slightly convex, and smooth, with distinct lateral bead and few lateral setae; neck and blade of prosternal process evenly jointed. Abdominal ventrite 6 slightly truncate.

Male: Antennae simple. Protarsomere 4 with large, thick, strongly curved anterolateral hook-like seta. Protarsomere 5 ventrally with anterior band of 19 and posterior row of 8 relatively long setae (Fig. 8A). Median lobe with slightly curved, rounded apex in lateral view and with almost truncate apex in ventral view, on both lateral sides with strong, short setae situated almost linearly on a half of distal part of median lobe under fine carina (Fig. 8 B–C). Paramere without notch, slightly concave on dorsal side and with dense setae on subdistal part; proximal setae inconspicuous (Fig. D). Abdominal ventrite 6 with 6-9 lateral striae on each side.

Holotype: TL-H 3.6 mm, TL 3.9 mm, MW 1.9 mm.

Female: Without evident differences in external morphology from males, except for not modified pro- and mesotarsi and abdominal ventrite 6 without striae.

Distribution.

Papua New Guinea: Morobe Province. The species is known only from the type locality (Fig. 40).

Etymology.

The species is named after Inji Mountain. The name is an adjective in the nominative singular.