Austrelatus sarmiensis, 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

27. Austrelatus sarmiensis sp. nov.

Figs 74 , 78 , 84

Type locality.

Indonesia: Papua Province: Sarmi Regency, Sarmi area, 01°58'17.0"S, 138°50'56.9"E, 70 m a.s.l.

Type material.

Holotype: male "Indonesia: Papua, Sarmi area 70 m, 25.ix.2014, -1.9713 138.8491, Menufandu (Pap032)" (MZB).

Paratype: 1 female with the same label as the holotype (ZSM).

Description.

Body size and form: Beetle small, with oblong-oval habitus (Fig. 74 ).

Measurements: TL 4.95-5.2 mm, TL-H 4.45-4.7 mm, MW 2.4-2.6 mm, TL/MW 2-2.06; PL 0.75-0.8 mm, PW 2.1-2.2 mm, PL/PW 0.36; DBE 0.85-0.9 mm, DBE/PW 0.41.

Holotype: TL 5.2 mm, TL-H 4.7 mm, MW 2.6 mm, TL/MW 2; PL 0.8 mm, PW 2.2 mm, PL/PW 0.36; DBE 0.9 mm, DBE/PW 0.41.

Colouration: Dorsally piceous, with yellowish red head (with brown spot medially) and pronotal sides, and with three reddish, vague, indistinct spots on elytral base and more distinct yellowish red spot on elytral apex (Fig. 74 ).

Head yellowish red, piceous narrowly behind eyes, brown anteriorly, and with large, brown median spot. Pronotum piceous, yellowish red narrowly on sides, broader at anterior angles. Elytron piceous, with three very vague, indistinct, yellowish red to reddish basal spots; most distinct spot at base of stria 10; at apex, with a distinct, rather small, elongate spot. Scutellum reddish brown to brown. Antennae and other head appendages yellow. Pro- and mesolegs yellow and metalegs yellowish red proximally and darker distally. Venter mostly piceous, with yellowish red prosternum.

Surface sculpture: Elytron with 11 distinct, complete dorsal striae; submarginal stria present: 11+1 (Fig. 74 ).

Head with strioles between eyes, with rather dense punctation (spaces between punctures 1-3 × size of punctures); punctures relatively small (diameter of punctures slightly smaller than diameter of cells of microreticulation); head with a row of 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; head with relatively strong microreticulation. Pronotum with numerous strioles in whole surface, without longitudinal wrinkles; pronotal punctation finer and sparser than on head; setigerous punctures form a broad row along pronotal margins, absent in posterior middle; disc of pronotum with thin, longitudinal median scratch. Pronotal microreticulation distinct. Elytron with 11 distinct, complete dorsal striae; odd striae shortly reduced apically; stria 10 shortly reduced basally; submarginal stria present, rather short, not reaching ½ of elytron. Elytron with fine punctation and distinct microreticulation. Ventral part with fine, inconspicuous punctation, slightly visible on metaventrite and metacoxae and stronger on abdominal ventrites; prosternum smooth medially; metaventrite and metacoxae with distinct microreticulation medially; on abdominal ventrites microreticulation almost invisible; metacoxal plates with short, numerous, strongly impressed 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 lateral area at each side.

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

Male: Protibia straight, not modified. Proclaws simple, relatively long, equal. Median lobe of aedeagus with two lobes of dorsal sclerite rather narrow; left lobe distinctly shorter than right one; left dorsal lobe almost straight to apex, with weak, longitudinal crest, its dorsal surface with distinct denticulation visible in left lateral view; right dorsal lobe with weakly developed, inconspicuous median impression in right lateral view, with broad, rounded apex. 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, thin, and straight apically, 2/3 of length of left dorsal lobe. Paramere with setae not divided into distal and proximal; more distally situated setae denser than more proximal ones (Fig. 78 ).

Female: With coarser and denser dorsal punctation, especially on elytron. There are no striolated, matt forms.

Affinities.

Based on shape of the median lobe, pronotal and elytral striolation, and in some measure dorsal colouration, the species is very similar to A. vagauensis sp. nov. but distinctly differs from it in much smaller body size and straighter median lobe sclerites.

Etymology.

The species is named after Sarmi area. The name is an adjective in the nominative singular.

Distribution.

New Guinean endemic. Indonesia: Papua Province: Sarmi Regency. The species is known only from the type locality (Fig. 84 ).

Habitat.

The species was collected in stream-side puddles and pools of an intermittent stream.

Figures

Figure 78. Austrelatus sarmiensis 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 84. Map of New Guinea showing distribution of 14 Austrelatus species.

Figures 74 - 77. Habitus and colouration of 74 Austrelatus sarmiensis sp. nov. 75 A. rugosus sp. nov. 76 A. debulensis sp. nov. 77 A. moreguinensis sp. nov.