Austrelatus bormensis, Shaverdo & Hájek & Hendrich & Surbakti & Panjaitan & Balke, 2023

Shaverdo, Helena, Hajek, Jiri, Hendrich, Lars, Surbakti, Suriani, Panjaitan, Rawati & Balke, Michael, 2023, Austrelatus gen. nov., a new genus of Australasian diving beetles (Coleoptera, Dytiscidae, Copelatinae), with the discovery of 31 new species from New Guinea, ZooKeys 1170, pp. 1-164 : 1

3. Austrelatus bormensis sp. nov.

Figs 32 , 35 , 82

Type locality.

Indonesia: Papua Province, Pegunungan Bintang Regency, near Borme, 04°24'S, 140°25'E, 900 m a.s.l.

Type material.

Holotype: male "IRIAN JAYA 12.8.1992 Zentralmassiv, Borme 04°24'S, 140°25'E 900 m, leg. Balke (8)" (ZSM).

Paratypes: IN: Papua: Pegunungan Bintang Regency: 10 males, 4 females with the same label as the holotype (MZB, NHMW, ZSM). 9 males, 4 females "Borme-Omban 13.8.1992 leg. Balke (9)" (NHMW). 2 males "IR 92#9: West New Guinea, Borme, 1200 m, 13.viii.1992 leg., Balke" (NHMW). 2 males, 2 females "Indonesia: Papua, Omban, 23.xi.2016, P.J.A. de Vries (Pap75)" (ZSM). 1 male "IRIAN JAYA Zentralmassiv 140°25'E 04°24'S ", "Kali Takime, 1000 m, 15.8.1992 leg. Balke (14)" (NHMW).

Yalimo Regency: 2 males "INDONESIA: West Papua, Jayawijaya Prov., Elelim, 450-750 m, 17.xii.2004, Riedel", one of them with an additional green label “1551” (ZSM).

Description.

Body size and form: Beetle medium-sized, with oblong-oval to elongate habitus (Fig. 32 ).

Measurements: TL 5.4-6.1 mm, TL-H 4.8-5.5 mm, MW 2.5-3.05 mm, TL/MW 2-2.16; PL 0.8-0.9 mm, PW 2.2-2.6 mm, PL/PW 0.34-0.36; DBE 0.95-1 mm, DBE/PW 0.39-0.43.

Holotype: TL 6.1 mm, TL-H 5.5 mm, MW 3.05 mm, TL/MW 2; PL 0.9 mm, PW 2.6 mm, PL/PW 0.35; DBE 1 mm, DBE/PW 0.39.

Colouration: Dorsally piceous, with reddish head, pronotal sides, and short basal band and apical spot on elytron (Fig. 32 ).

Head reddish brown, darker narrowly behind eyes. Pronotum brown, with paler towards sides, almost yellowish red on them. Elytron dark brown to piceous, often with reddish yellow to reddish brown short band on middle of elytral base, formed by confluence of two spots, which seldom present as almost separate, vague spots; band of different length but not reaching suture and lateral elytral margin; rather broad and distinct or narrow and vague; elytron with distinct, elongate apical spot. Scutellum brown to piceous. Antennae and other head appendages yellowish brown. Legs reddish yellowish brown proximally and darker distally, especially metalegs. Venter mostly brownish, with paler prosternum. Teneral beetles paler.

Surface sculpture: Elytron with 5-10 more or less complete dorsal striae, submarginal stria usually absent: (5-10)+(0-1) (Fig. 32 ).

Head without strioles, with relatively dense, distinct punctation (spaces between punctures 1-2 × size of punctures); punctures relatively coarse (diameter of punctures equal to diameter of microreticulation cells); head with a row of coarse setigerous punctures along inner margin of each eye and a short row at frontal angle of each eye; a slightly longer puncture row forms fronto-clypeal depression at each head side; microreticulation distinct but not strong. Pronotum usually with distinct, numerous strioles, occupying whole pronotum, sparse and finer on disc and coarse and dense laterally from it, especially at posterior margin; pronotal punctation finer than on head; setigerous punctures form a row along pronotal margins, absent in posterior middle, generally less distinct because of strioles; disc of pronotum with indistinct longitudinal median scratch. Pronotal microreticulation rather weakly impressed. Pronotum often with numerous strioles in females. Elytron with 5-10 dorsal striae, usually with six complete striae and interrupted striae between them; very seldom with strong reduction of striae, to five incomplete striae; submarginal striae usually absent. Elytron with very fine, inconspicuous punctation and very weak microreticulation. Elytron often with numerous strioles in females. Ventral part with fine, inconspicuous punctation, invisible on metaventrite and metacoxae and weak on abdominal ventrites; prosternum smooth medially; metaventrite and metacoxae with weak microreticulation; on abdominal ventrites microreticulation almost invisible; metacoxal plates with short, numerous longitudinal strioles, abdominal ventrites 1 and 2 with numerous, long, longitudinal strioles from margin to margin, on abdominal ventrites 3 and 4 strioles situated laterally and turn to middle, almost horizontal, abdominal ventrites 5 and 6 without strioles but with rather distinct punctation that sparser medially and forms a dense, rugose lateral area at each side.

Structures: Head relatively broad. Pronotum short and broad; lateral margins distinctly convergent anteriorly. Base of prosternum narrowly rounded anteriorly, convex medially; blade of prosternal process relatively broad, convex in middle.

Male: Protibia not straight, thinner proximally and broader medially and distally due to its curved ventral margin. Proclaws relatively long, equal. Median lobe of aedeagus with two lobes of dorsal sclerite broad, almost straight, slightly curved downwards apically; right dorsal lobe slightly longer and broader than left one, with a broad but pointed apex and large median membranous impression in right lateral view; in left lateral view, left dorsal lobe with a lateral longitudinal crest. Lobes of ventral sclerite weakly sclerotised laterally (visible in left and right lateral views), mostly membranous, subequal, straight apically; sclerotised part of left ventral lobe long, with thin, straight apex (in left lateral view). Paramere with setae not divided into distal and proximal (Fig. 35 ).

Female: Most of the females have numerous thin, longitudinal strioles on elytra and pronotum that densely cover dorsal surface and make it matt.

Variability.

The species demonstrates insignificant variation in its dorsal colouration and strong variation in elytral striation described above.

Affinities.

Based on general appearance and shape of the median lobe, the species is close to A. neoguineensis . But differs from it in smaller size, unstable number of elytral striae: (5-10)+(0-1), in A. neoguineensis : 6+(0-1), pronotum with strioles, and shape of median lobe sclerites.

Etymology.

The species is named after its type locality, Borme. The name is an adjective in the nominative singular.

Distribution.

New Guinean endemic. Indonesia: Papua Province: Pegunungan Bintang and Yalimo regencies (Fig. 82 ).

Habitat.

The species was collected in stream-side puddles.

Figures

Figure 35. Austrelatus bormensis sp. nov., median lobe A left lateral view B right lateral view C ventral view D left paramere in external view E right paramere in internal view. Scale bar: one unit - 0.1 mm (A-C).

Figure 82. Map of New Guinea showing distribution of 11 Austrelatus species.

Figures 29 - 32. Habitus and colouration of 29 Austrelatus brazza sp. nov., without elytral striae 30 A. brazza sp. nov., with elytral striae 31 A. lisae sp. nov. 32 A. bormensis sp. nov.