Austrelatus fumato, 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

Austrelatus fumato sp. nov.

Figs 9 , 10 , 13

Type locality.

Indonesia: West Papua Province: Manokwari Regency, Fumato, 0°54'15.4"S, 132°43'11.3"E, 820 m a.s.l.

Type material.

Holotype: male, Indonesia: Papua Barat, Fumato, forest stream, 820 m, -0.9042 132.7198 (BH027), 6209 [green text] (MZB).

Paratypes: IN: West Papua: Manokwari Regency: 3 males, 1 female with the same label as the holotype, one male additionally with green text label “6210” (KSP, NHMW, ZSM).

Kaimana Regency: 2 males, 2 females "INDONESIA: W-Papua 50km SE Kaimana, Triton bay, vic. Kamaka vill. trail to Kamakawalar lake, 3°48'22"S 134°14'02"E, 50-100 m, 03.II.2011 leg. A Skale (006a) small pool" (NHMW, ZSM). 1 male "INDONESIA: W-Papua ca. 50km SE Kaimana, Triton bay, vic. Kamaka village, trail to Kamakawalar lake, 3°48'22"S, 134°14'02"E, 50-100 m, 03.II.2011 leg. A Skale (006a)", “4438” [green text] (ZSM). 1 female "Ir 27-W.New Guinea, Fak-Fak, Kali Mati 4km N F.-F., 260 m, 8.-9.viii.1991 Balke & Hendrich leg." (ZSM).

Sorong Regency: 1 male "Indonesia: Papua Barat, Sorong-Teminabuan, 50 m, 2.x.2014, -1,1092904 131,6125645 (BH046)", “6450” [green text] (ZSM).

Papua: Nabire/Painai Regencies: 2 males, 1 female "Irian Jaya: Paniai Prov. road Nabire - Ilaga, km 54, 30.8.1996, 750 m leg. M. Balke (96 # 9)" (NHMW). 1 male, 2 females "IRIAN JAYA: Nabire dist. rd. Nabire-Ilaga, km 54 03°29.51'S, 135°43.91'E, 750 m, IV. 1998 leg. Balke", “Restpfütze eines Baches" (NHMW).

Description.

Body size and form: Beetle medium-sized, relatively broad, with oval, egg-shaped habitus (Fig. 9A, B ).

Measurements: TL 5.1-5.8 mm, TL-H 4.6-5.3 mm, MW 2.7-3.1 mm, TL/MW 1.78-1.92; PL 0.7-0.9 mm, PW 2.3-2.7 mm, PL/PW 0.3-0.35; DBE 1.0-1.1 mm, DBE/PW 0.41-0.43.

Holotype: TL 5.5 mm, TL-H 5.05 mm, MW 3.1 mm, TL/MW 1.78; PL 0.9 mm, PW 2.55 mm, PL/PW 0.35; DBE 1.1 mm, DBE/PW 0.43.

Colouration: Dorsally yellowish, with dark brown pronotal disc and thin dark brown lines along elytral striae (Fig. 9A, B ).

Head pale yellow to dark yellow, dark brown behind eyes and narrowly yellowish brown to brown posteriorly. Pronotum pale yellow to dark yellow, with a large dark brown area on disc from anterior to posterior margins, sides of this brown area concave; sometimes dark brown colouration continues as a narrow band along posterior margin till lateral bead. Elytron pale yellow to dark yellow, with thin dark brown lines tracing precisely elytral striae; margins of lines sometimes vague and spaces between lines sometimes yellowish brown on elytral disc; sometimes elytron darker due to broader, vague dark brown lines, merged together, especially on elytral disc. Antennae and other head appendages yellow to dark yellow. Pro- and mesolegs yellow proximally and yellowish brown distally, metalegs darker. Venter brown to dark brown, with paler prosternum.

Surface sculpture: Dorsally with 4-11 often uncomplete elytral dorsal striae, submarginal stria absent: (4-11)+0 (Fig. 9A, B ).

Head without strioles, with relatively dense, even punctation (spaces between punctures 1-3 × size of punctures); punctures relatively large (diameter of punctures more or less equal to diameter of cells of microreticulation) but not coarse; head with a small uneven median depression probably due to some coarser punctures at each side; a row of coarse setigerous punctures along inner eye margin present; a very short row of such punctures present at frontal angle of each eye and a longer puncture row forms fronto-clypeal depression at each head side; head with strong microreticulation. Pronotum with several short strioles at very posterior angles and longitudinal wrinkles along lateral parts of posterior margin; pronotal punctation slightly finer and sparser than on head; coarse setigerous punctures form a row along anterior margin and in lateral and basolateral depressions; some coarse setigerous punctures also evident along lateral parts of posterior margin; disc of pronotum with a short, thin, longitudinal median scratch and sometimes with two small, oval, shallow, transverse lateral depressions. Pronotal microreticulation distinct. Elytron with maximum 11 dorsal striae: stria 1 often completely absent, if present, distinctly shortened and interrupted basally and especially apically: almost to the elytral half; striae 2 and 3 usually absent, rarely present as sparse strioles or complete; stria 4 usually visible as first elytral stria, relatively strongly impressed or present as a row of strioles; striae 5-7 strongly reduced: absent, or present as sparse strioles, rarely as rows of strioles apically or more or less complete, shortened and/or interrupted basally; striae 8-11 distinct, striae 9 and 10 sometimes reduced basally; a few additional very short striae can be present between striae, especially between striae 9-11; submarginal stria absent; elytral punctation fine, sparse or more distinct; single coarse, setigerous punctures observed in striae; microreticulation weak. Ventral part with very fine, scarce, inconspicuous punctation, invisible on metaventrite and metacoxae and more distinct on abdominal ventrites; prosternum smooth medially; metaventrite and metacoxae with distinct, strong microreticulation, much weaker medially; abdominal ventrites with very weakly impressed microreticulation; metacoxal plates with several longitudinal strioles, abdominal ventrites 1 and 2 with numerous, long, longitudinal strioles from margin to margin, on abdominal ventrites 3-5 strioles situated laterally and turn to middle, almost horizontal, abdominal ventrite 6 with a few very inconspicuous, small strioles near row of setigerous punctures at each side; abdominal ventrites 5 and 6 with distinct punctation that sparser medially and forms a very dense lateral area at each side.

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

Male: Protibia straight, not modified. Proclaws long, equal in length. Median lobe of aedeagus broad, sickle-shaped, with dorsal and ventral sclerites not separated medially, strongly pressed together. Dorsal sclerite without distinct surface sculpture, smooth; divided into two lobes apically; lobes developed more or less identically strong, with broadly pointed, slightly curved downwards apexes in lateral view. Ventral sclerite more weakly sclerotised than dorsal one, of complex folded form, not divided into two lobes. Paramere of narrow elongate form, with short setae of subequal length, not divided into distal and proximal (Fig. 10 ).

Female: Pronotal strioles more numerous than in males.

Variability.

There is a significant variability in the elytral striation and colouration among the populations. The specimens from Fumato show especial differences from the other material having 11 almost complete dorsal striae on elytron, almost yellow dorsal colouration, finer elytral punctation and shorter setae of the paramere. The single specimen from Fakfak has a piceous, without striae disc of the elytron, while the single beetle from Sorong has, similar to Fumato specimens, almost yellow elytra but only five or six dorsal striae on elytron (Fig. 9B ).

Affinities.

The species is very characteristic in general appearance and structure of the male genitalia; therefore, it can be easily distinguished from the other New Guinean Austrelatus . Based on shape of their median lobe, they remind representatives of the A. neoguineensis group but distinctly differs from them by the ventral sclerite not divided into two lobes, the narrow shape of the paramere and its shorter, even setation.

Etymology.

The name refers to the Fumato Village where the specimens with more intensively striated elytra were collected. The species name is a noun in the nominative singular, standing in apposition.

Distribution.

New Guinean endemic. Indonesia: West Papua and Papua provinces (Fig. 13 ).

Habitat.

The single specimen from Fakfak, Kali Mati was collected in a water-filled tree hollow, shaded by primary rainforest. The specimens from Nabire were collected in a small rest pool of a forest stream.

Figures

Figure 10. Austrelatus fumato 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 13. Map of New Guinea showing distribution of Austrelatus clarki (Sharp, 1882), A. fumato sp. nov., and A. setiphallus sp. nov.

Figures 8, 9. 8 Austrelatus clarki (Sharp, 1882) A median lobe in left lateral view B habitus and colouration of holotype of Copelatus vagestriatus Zimmermann, 1919, syn. nov., female 9 Austrelatus fumato sp. nov., habitus and colouration of A holotype B specimen from Sorong.