Exocelina irianensis Shaverdo, Hendrich & Balke

Shaverdo, Helena V., Surbakti, Suriani, Hendrich, Lars & Balke, Michael, 2012, Introduction of the Exocelina ekari-group with descriptions of 22 new species from New Guinea (Coleoptera, Dytiscidae, Copelatinae), ZooKeys 250, pp. 1-76 : 19-21

14. Exocelina irianensis Shaverdo, Hendrich & Balke sp. n. Figs 12 A–E, 38

Type locality.

Indonesia: Papua Province: Nabire/Paniai Regencies, road Nabire-Enarotali, 54th km, 03°29.52'S, 135°43.91'E.

Type material.

Holotype: male "West New Guinea/Paniai Prov./IR19 track Nabire-Ilaga km 54 Basecamp, 750-800m, 16.-27.7.1991 leg: Balke & Hendrich" (CLH). Paratypes: 7 males, 6 females with the same label as the holotype (CLH). 8 males "IR90-11: W. New Guinea, Trek Nabire-Ilaga, km55, 19.-25.ix.1990, Balke" (ZSM). 9 males "W.-Neuguinea/Paniai Prov. Strasse Nabire-Ilaga km 54 700m, 22.-25.9.1990/IR 11 leg: Balke & Hendrich" (ZSM, CLH). 3 males "IRIAN JAYA: Paniai Prov. road Nabire-Ilaga, km 54 26./27.8.1996, 750-800m leg. M. Balke (96 # 2)" (NHMW). 1 male "IRIAN JAYA: Paniai Prov. road Nabire-Ilaga, km 54 30.8.1996, 750m leg. M. Balke (96 # 9)", "DNA M.Balke 3264" [green] (NHMW). 31 males "IRIAN JAYA: Paniai Prov. road Nabire-Ilaga, km 117 Unipo, 2.9.1996, 150m leg. M. Balke (96 # 12)" (NHMW). 4 males "IRIAN JAYA: Paniai Prov. road Nabire-Ilaga, km 54 10.9.1996, 800m leg. M. Balke (96 # 20)", 1 male of them with a green label "DNA M.Balke 3265" (NHMW). 3 males, 2 females "IRIAN JAYA: Nabire Prov. Nabire-Ilaga, km 35 Kali Cemara, 27.9.1997 leg. M. Balke (# 5)" (NHMW). 1 male, 1 female "IRIAN JAYA: Nabire Prov. rd. Nabire-Ilaga, Km 54 ca. 750m, X.1997 leg. Balke" (NHMW). 5 exs. "Irian Jaya: Nabire distr., road Nabire-Ilaga, km 54, 03 29'517"S, 135 43'913"E, 750m, iv.1998 M. Balke leg." (NHMW). 13 males "Indonesia: Papua, Road Nabire-Enarotali KM 55, 774m, 22.x.2011, 03 29.796S, 135 43.885E, Uncen (PAP09)", two of them additionally with labels "DNA M. Balke 4906", "DNA M. Balke 4907" (NHMW, ZSM). 1 male "Indonesia: Papua, Road Nabire-Enarotali KM 80, 250m, 22.x.2011, 03 33.860 S, 135 46.473E, Uncen (PAP12)" (ZSM). 1 male "Indonesia: Papua, Road Nabire-Enarotali KM 95, 160m, 22.x.2011, 03 34.193S, 135 49.246E, Uncen (PAP13)" (ZSM). 12 males "Indonesia: Papua, Road Nabire-Enarotali KM 52, 555m, 23.x.2011, 03 30.107S, 135 42.971E, Uncen (PAP17)" (MZB, NHMW, ZSM). 1 male, 1 female "Indonesia: Papua, Road Nabire-Enarotali KM 40, 350m, 23.x.2011, 03 29.314S, 135 41.188E, Uncen (PAP18)" (ZSM).1 female "Indonesia: Papua, Road Nabire-Enarotali KM 62, 340m, 22.x.2011, 03 31.684S, 135 42.802E, Uncen (PAP11)", "DNA M. Balke 4917", note: accessory of this female to the species is based on DNA data (MZB).

Additional material.

29 females "IRIAN JAYA: Paniai Prov. road Nabire-Ilaga, km 117 Unipo, 2.9.1996, 150m leg. M. Balke (96 # 12)" (NHMW). These females are most likely a mixture of two species: Exocelina irianensis sp. n. and Exocelina unipo sp. n. 13 females "Indonesia: Papua, Road Nabire-Enarotali KM 55, 774m, 22.x.2011, 03 29.796S, 135 43.885E, Uncen (PAP09)" (NHMW, ZSM). These females are most likely a mixture of two species: Exocelina irianensis sp. n. and Exocelina weylandensis sp. n. 12 females "Indonesia: Papua, Road Nabire-Enarotali KM 80, 250m, 22.x.2011, 03 33.860S, 135 46.473E, Uncen (PAP12)" (NHMW, ZSM). These females are most likely a mixture of three species: Exocelina irianensis sp. n., Exocelina soppi sp. n., and one additional new species. 13 females "Indonesia: Papua, Road Nabire-Enarotali KM 95, 160m, 22.x.2011, 03 34.193S, 135 49.246E, Uncen (PAP13)" (NHMW, ZSM). These females are most likely a a mixture of two species: Exocelina irianensis sp. n. and Exocelina unipo sp. n. 21 females "Indonesia: Papua, Road Nabire-Enarotali KM 52, 555m, 23.x.2011, 03 30.107S, 135 42.971E, Uncen (PAP17)" (NHMW, ZSM). These females are most likely a mixture of two species: Exocelina irianensis sp. n. and Exocelina soppi sp. n. 9 females "IRIAN JAYA: Paniai Prov. road Nabire-Ilaga, km 54 10.9.1996, 800m leg. M. Balke (96 # 20)". These females are most likely a mixture of four species: Exocelina irianensis sp. n., Exocelina ekari sp. n., Exocelina weylandensis sp. n., and Exocelina kakapupu sp. n. 8 females "IRIAN JAYA: Paniai Prov. road Nabire-Ilaga, km 54 26./27.8.1996, 750-800m leg. M. Balke (96 # 2)" (NHMW). These females are most likely a mixture of two species: Exocelina irianensis sp. n. and Exocelina kakapupu sp. n. 8 females "W.-Neuguinea/Paniai Prov. Strasse Nabire-Ilaga km 54 700m, 22.-25.9.1990/IR 11 leg: Balke & Hendrich" (ZSM, CLH). These females are most likely a mixture of three species: Exocelina irianensis sp. n., Exocelina weylandensis sp. n., and Exocelina soppi sp. n.

Diagnosis.

Beetle small, reddish-brown to dark brown, usually with paler head and pronotal sides; shiny; pronotum without lateral bead; male antennomeres 3-5 distinctly enlarged; male protarsomere 4 with large, thick, evidently curved anterolateral hook; median lobe with very strong submedian constriction, distal and proximal parts equally broad, and symmetrical apex in ventral view; paramere with shallow notch on dorsal side and subdistal part short and small, with not numerous, relatively short, thick, and flattened setae. The species differs from other ones by the pronotum without lateral bead and modified antennae of the males.

Description.

Size and shape: Beetle small (TL-H 3.2-3.85 mm, TL 3.55-4.25 mm, MW 1.7-2.05 mm), with oblong-oval habitus, broadest at elytral middle. Coloration: Head uniformly reddish to dark brown, in a few specimens darker posteriorly; pronotum reddish-brown to dark brown, with paler sides, in a few specimens uniformly colored; elytra uniformly reddish-brown to dark brown; head appendages yellowish-red, legs darker (Fig. 38).

Surface sculpture: Head with dense punctation (spaces between punctures 1-3 times size of punctures), evidently finer and sparser anteriorly; diameter of punctures smaller than diameter of cells of microreticulation. Pronotum with a little sparser but much finer punctation than on head, almost invisible. Elytra with extremely sparse and fine punctation. Head, pronotum, and elytra with weakly impressed microreticulation, dorsal surface, thus, shiny. Head with microreticulation stronger. Metaventrite and metacoxa distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles. Abdominal sternites with distinct microreticulation, strioles, and fine sparse punctation, coarser and denser on two last abdominal sternites.

Structures: Pronotum without lateral bead, in some specimens with indistinct traces of bead. Base of prosternum and neck of prosternal process with distinct ridge, without anterolateral extensions. Blade of prosternal process lanceolate, relatively broad, slightly convex, with distinct bead and few setae; neck and blade of prosternal process evenly jointed. Abdominal sternite 7 broadly truncate apically, in some specimens very distinctly, in some less.

Male: Antennomeres 3 and 4 strongly enlarged, evidently larger than other, antennomere 5 distinctly enlarged, 6-9 robust (Fig. 12A); antennomeres 3-6 strongly and 7-9 somewhat rugose ventrally. Protarsomere 4 with large, thick, evidently curved anterolateral hook. Protarsomere 5 ventrally with anterior row of 9 short setae and posterior row of 5 short setae (Fig. 12B). Abdominal sternite 7 with 4-7 lateral striae on each side. Median lobe with very strong submedian constriction, distal and proximal parts equally broad, and symmetrical apex in ventral view (Figs 12C). Paramere with shallow notch on dorsal side and subdistal part short and small, with not numerous, relatively short, thick, and flattened setae (Fig. 12E).

Female: Antenna simple; traces of bead on pronotal sides are more often observed than in males; abdominal sternite 7 without striae.

Distribution.

Indonesia: Papua Province. This species is known from Nabire and Paniai Regencies (Fig. 50).

Etymology.

The name is derived from the Biak (northern coast of New Guinea) islanders’ word “Irian”, which means "hot island emerging from the sea" and refers to New Guinea. The species name is an adjective in the nominative singular.