Austrelatus toricelli, 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

30. Austrelatus toricelli sp. nov.

Figs 47 , 51 , 83

Type locality.

Papua New Guinea: Sandaun Province, Toricelli Mountains, south from Sibilanga Station, 03°39'07.3"S, 142°29'59.5"E, 350 m a.s.l.

Type material.

Holotype: male "Papua New Guinea: Sandaun, Toricelli Mts., 2h walk fr Sibilanga Stn, 350 m, 19.iv.2006, 03.39.121S 142.29.991E, Balke (PNG 44)" (ZSM).

Description.

Body size and form: Beetle medium-sized, with oblong-oval habitus (Fig. 47 ).

Measurements: Holotype: TL 5.7 mm, TL-H 5.15 mm, MW 2.75 mm, TL/MW 2.07; PL 0.85 mm, PW 2.4 mm, PL/PW 0.35; DBE 0.95 mm, DBE/PW 0.4.

Colouration: Dorsally dark brown, with almost piceous elytra, yellowish red head, pronotal sides, and spots on elytral base and apex (Fig. 47 ).

Head yellowish red, dark brown narrowly behind eyes. Pronotum yellowish red to reddish brown, with darker anterior and posterior margins and narrowly disc and paler sides; darkest parts along middle of anterior and posterior margins. Elytron piceous, dark brown narrowly on disc, with two yellowish red basal spots medially, confluent, forming a short band, not reaching lateral elytral margin; at base of striae 1 and 2, with a very vague brownish spot; at apex, with a distinct, rather small, elongate spot. Scutellum reddish brown. Antennae and other head appendages yellow. Pro- and mesolegs yellow and metalegs yellowish red proximally and darker distally. Venter mostly yellowish red.

Surface sculpture: Elytron with 10 dorsal striae (most of them complete) due to strong reduction to few strioles of stria 1 (using 11- stria pattern); submarginal stria present: 10+1 (Fig. 47 ).

Head without strioles, with sparse, inconspicuous punctation (spaces between punctures 1-4 × size of punctures); punctures relatively small, weakly impressed (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; these rows weakly impressed; head with relatively strong microreticulation. Pronotum with sparse strioles along posterior margin, denser laterally, with longitudinal wrinkles at middle of posterior margin; pronotal punctation slightly finer 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 rather weakly impressed on disc. Elytron with ten more or less complete dorsal striae. Using 11-stria pattern: striae 2, 4, 6, 8, 10, and 11 complete, stria 1 absent or present as fine strioles in apical half, striae 3, 5, and 7 interrupted in whole their length, stria 9 present only in basal 1/3 of elytron. Elytron with very fine, inconspicuous punctation; microreticulation weak. 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 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 and6 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, subequal; in lateral left view, left dorsal lobe apically with longitudinal crest, its apex almost straight, pressed to right dorsal lobe; right dorsal lobe with weakly developed, inconspicuous median impression in right lateral view, more or less rounded apex and small crest on its left side where apex of left dorsal lobe placed in left lateral view. 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 in left lateral view. Paramere with setae not divided into distal and proximal; more distally situated setae slightly denser than more proximal ones (Fig. 51 ).

Female: Unknown.

Affinities.

Based on general shape of the median lobe, the species is very similar to A. sandaunensis sp. nov. but differs from it in elytral striation and shape of median lobe sclerites; for details, see under A. sandaunensis sp. nov.

Etymology.

The species is named after its type locality, Toricelli Mts. The name is a noun standing in apposition.

Distribution.

New Guinean endemic. Papua New Guinea: Sandaun Province, Toricelli Mts. The species is known only from the type locality (Fig. 83 ).

Habitat.

The species was collected in a puddle by the forest edge.

Figures

Figure 51. Austrelatus toricelli 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 83. Map of New Guinea showing distribution of seven Austrelatus species.

Figures 44 - 47. Habitus and colouration of 44 Austrelatus fojaensis sp. nov. 45 A. fakfak sp. nov. 46 A. manokwariensis sp. nov. 47 A. toricelli sp. nov.