Exocelina andakombensis 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 : 50-52

Taxon classification Animalia Coleoptera Dytiscidae

4. Exocelina andakombensis Shaverdo & Balke sp. n. Figs 7, 29

Exocelina undescribed sp. MB1361: Toussaint et al. 2014: supplementary figs 1-4, tab. 2.

Type locality.

Papua New Guinea: Gulf Province, Marawaka, Andakombe towards Morobe, 07°08.96'S; 145°45.48'E, 1000 m a.s.l.

Type material.

Holotype: male "Papua New Guinea: Gulf, Marawaka, Andakombe towards Morobe, 1000m, 12.xi.2006, 07.08.958S 145.45.482E, Balke & Kinibel (PNG 91)" (ZSM). Paratypes: Morobe: 1 male, 4 females "Papua New Guinea: Morobe, Herzog Mts., Bundun, 700-800m, 2.iv.2006, 06.51.598S 146.37.07E, Balke & Sagata (PNG 27)", the male additionally with a green label "DNA M.Balke 1314" (NHMW, ZSM). Gulf: 2 males, 1 female with the same label as the holotype (NHMW, ZSM). 1 male "Papua New Guinea: Gulf, Marawaka, Andakombe towards Morobe, 1500m, 12.xi.2006, 07.10.413S 145.49.555E, Balke & Kinibel (PNG 93)", "DNA M.Balke 1361" [green] (ZSM). 2 males "Papua New Guinea: Gulf, Marawaka, Mala, 1400m, 11.xi.2006, 07.05.664S 145.44.467E, Balke & Kinibel (PNG 90)" (ZSM). 3 males, 1 female "Papua New Guinea: Gulf, Marawaka, nr Ande, 1000m, 10.xi.2006, 07.03.598S 145.44.375E, Balke & Kinibel (PNG 89)" (NHMW, ZSM).

Diagnosis.

Beetle small; piceous, with brown head and pronotum; matt, with strong punctation and microreticulation; male antennae simple; protarsomere 4 with weakly curved anterolateral hook-like seta, equal to more laterally situated large seta; median lobe with slightly curved, rounded apex in lateral view and with slightly concave apex in ventral view, on both lateral sides with strong, relatively long setae situated broad-linearly on anterior half of distal part of median lobe; paramere without notch on dorsal side. The species is very similar to Exocelina injiensis sp. n. but differs from it in small, equal to laterally situated large seta, weakly curved anterolateral hook-like seta of protarsomere 4 (large, thick, strongly curved anterolateral hook-like seta in Exocelina injiensis sp. n.), shorter and less numerous ventral setae of protarsomere 5, and absence of fine lateral carina, bordering shorter distal setae, on the median lobe.

Description.

Size and shape: Beetle small (TL-H 3.15-3.55 mm, TL 3.55-4.1 mm, MW 1.7-1.95 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, sometimes piceous on disc; elytra piceous, dark brown laterally, with narrow reddish sutural lines; head append ages and legs proximally yellowish red, legs distally darker, reddish brown, especially metathoracic legs (Fig. 29). Teneral specimens paler.

Surface sculpture: Head with very dense punctation (spaces between most of punctures equal size of punctures), sparser anteriorly; diameter of most of punctures equal diameter of cells of microreticulation. Pronotum and elytra with sparser and slightly finer punctation than on head. Pronotum and elytra with strongly impressed microreticulation, dorsal surface matt. Head with microreticulation stronger. Metaventrite and metacoxa distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles, abdominal ventrites with distinct microreticulation and strioles. Metaventrite medially, metacoxal plates, and abdominal ventrites with sparse but distinct punctation.

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 small (equal to laterally situated large seta), weakly curved anterolateral hook-like seta; small setae around it reduced. Protarsomere 5 ventrally with anterior row of 8 and posterior row of 3 short setae (Fig. 7A). 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. Paramere without notch, slightly concave on dorsal side and with dense setae on subdistal part; proximal setae inconspicuous (Fig. 7 B–D). Abdominal ventrite 6 with 6-9 lateral striae on each side.

Holotype: TL-H 3.25 mm, TL 3.6 mm, MW 1.75 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: Gulf and Morobe Provinces (Fig. 40).

Etymology.

The species is named after Andakombe Village. The name is an adjective in the nominative singular.