Exocelina wareaga 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 : 72-75

Taxon classification Animalia Coleoptera Dytiscidae

14. Exocelina wareaga Shaverdo & Balke sp. n. Figs 17, 33

Exocelina undescribed sp. MB3404: Toussaint et al. 2014: supplementary figs 1-4, tab. 2.

Type locality.

Papua New Guinea: Central Province, Moroka, Kailaki, 09°24.13'S; 147°33.52'E, 827 m a.s.l.

Type material.

Holotype: male "Papua New Guinea Central, Moroka, Kailaki Wareaga, 760m, 27x2009 9.25.424S 147.31.068E Sagata (PNG227)" (ZSM). Paratypes: Central: 39 males, 46 females with the same label as the holotype (NHMW, ZSM). 7 males, 6 females "Papua New Guinea: Central, Moroka area, Kailaki, 827 m, 26.x.2009, 9.24.134S 147.33.521E, Sagata (PNG225)" (NHMW, ZSM). 10 males, 3 females "Papua New Guinea Central, 755m, 28.x.2009 S9 25 47 5 E147 32 59.1, Sagata (PNG229)" (NHMW, ZSM). 2 males, 2 females "Papua New Guinea: Central, Kokoda Trek, 980m, i.2008, 09 15.933S 147 36.590E, Posman (PNG 169)", one male and female with green labels "DNA M.Balke 3410" and "DNA M.Balke 4118" correspondently (NHMW, ZSM). 4 males, 6 females "Papua New Guinea: Central, Kokoda Trek, 320m, i.2008 09 19.236S 147 31.791E, Posman (PNG 168)", one male with a green label "DNA M.Balke 3404" (NHMW, ZSM). 3 males, 2 females "Papua New Guinea: Central, Kokoda Trek, 590m, i.2008, 09 14.339S 147 36.920E, Posman (PNG 170)" (NHMW, ZSM). National Capital District: 1 male "Papua New Guinea: National Capital District, Varirata NP, 600m, 16.xii.2007, 09.26.13S 147.22.09E, Balke & Sagata (PNG 159)" [specimen without head and pronotum] (ZSM).

Diagnosis.

Beetle medium-sized, dark brown, with paler, reddish-brown, head and pronotum; dorsal surface with fine punctation and evident microreticulation, shiny; pronotum with distinct lateral bead; male antennomeres simple; male protarsomere 4 with large, thick, strongly curved anterolateral hook-like seta; median lobe robust, apicolaterally with thick margins bordered with dorsolateral carina, with slightly curved, broad apex in lateral view and with truncate apex in ventral view, on both lateral sides with numerous fine setae situated linearly on anterior half of distal part of median lobe; paramere with very shallow notch on dorsal side. The species is very similar to Exocelina varirata sp. n. but differs from it in the shape of the median lobe: it is more robust, lateral margins apically and subapically thicker, bordered with a dorsolateral carina; also fine distal setae on lateral sides of the median lobe are situated linearly.

Description.

Size and shape: Beetle medium-sized (TL-H 3.65-4.4 mm, TL 4.05-4.8 mm, MW 1.95-2.35 mm), with oblong-oval habitus, broadest at elytral middle. Coloration: Head reddish-brown, dark brown behind eyes; pronotum reddish-brown, dark brown on disc; elytra uniformly brown to dark brown; ventrally reddish-brown, slightly darker on metacoxal plates; head appendages red to reddish-brown, legs darker distally (Fig. 33). Teneral specimens paler, with yellowish-red head and pronotum and pale brown elytra.

Surface sculpture: Head with relatively dense and coarse punctation (spaces between punctures 1-3 times size of punctures); diameter of punctures smaller than diameter of cells of microreticulation. Pronotum with finer, sparser, and more evenly distributed punctation than on head. Elytra with finer, sparser punctation than on pronotum, punctation very fine but evident. Pronotum and elytra with distinct microreticulation, dorsal surface shiny. Head with microreticulation slightly stronger. Metaventrite, metacoxa, and abdominal ventrites distinctly microreticulate, but with cells of microreticulation larger than on dorsal side. Metacoxal plates with longitudinal strioles and transverse wrinkles; abdominal ventrites with strioles. Ventrum with inconspicuous punctation, more evident on metacoxal plates and two last abdominal ventrites.

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 slightly truncate.

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 13 relatively long, thin setae (Fig. 17A). Abdominal ventrite 6 with 3-5 lateral striae on each side. Median lobe robust, apicolaterally with thick margins bordered with dorsolateral carina, with slightly curved, broad apex in lateral view and with truncate apex in ventral view, on both lateral sides with numerous fine setae situated linearly on anterior half of distal part of median lobe (Fig. 17 B–C). Paramere with very shallow notch on dorsal side, with thin, sparse, inconspicuous proximal setae and thicker, denser, and longer subdistal setae (Fig. 17D).

Holotype: TL-H 4.15 mm, TL 4.55 mm, MW 2.25 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: Central and National Capital District Provinces (Fig. 40).

Etymology.

The species is named after Wareaga village. The name is a noun in the nominative singular standing in apposition.