Austrelatus fakfak, 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

6. Austrelatus fakfak sp. nov.

Figs 45 , 49 , 83

Type locality.

Indonesia: West Papua Province: Fakfak Regency, 4 km N Fakfak, Kali Mati, 02°53'52.5"S, 132°18'23.8" Е, 260 m a.s.l.

Type material.

Holotype: male "West New Guinea/Fak-Fak/IR 27 Kali Mati, 4km N of Fak-Fak 260 m, 8. & 9.8.1991 leg: Balke & Hendrich" (ZSM).

Paratypes: IN: West Papua: Fakfak Regency: 4 males, 2 females, same label data as holotype, one male with hand-written label “Baumhöhlen-Art ex Fak-Fak" (CLH, MZB, NHMW). 17 males, 6 females "Indonesia: Irian Jaya Barat, Fak Fak, 310 m, 23.ii.2006, 2.53.756S 132 18.074E, Tindige, (FakFak)" (MZB, NHMW, ZSM). 1 male "Indonesia: Irian Jaya Barat, Fak Fak, 310 m, 23.ii.2006, Tindige", “1322” [green label] (ZSM).

Kaimana Regency: 1 male "Indonesia: W-Papua vic. Kaimana, road 18 km NE 3°31'11"S, 133°40'15"E, 50-80 m 21.-25.II.2011 leg. A. Skale (014)", “4429” [green label] (ZSM). 1 male, 1 female "INDONESIA: W-Papua ca. 50km SE Kaimana, Triton bay, vic. Kamaka village, trail to Kamakawalar lake, S3°48'22"/E134°14'02", 50-100 m, 03.II.2011 leg. A Skale (006a)", “4428” [green label] and “4437” [green text], respectively (ZSM). 4 males, 3 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" (CAS, NHMW).

Description.

Body size and form: Beetle small, with oblong-oval to elongate habitus (Fig. 45 ).

Measurements: TL 4.4-5 mm, TL-H 4-4.55 mm, MW 2.1-2.5 mm, TL/MW 2-2.23; PL 0.6-0.7 mm, PW 1.8-2.1 mm, PL/PW 0.33-36; DBE 0.8-0.95 mm, DBE/PW 0.44-0.45.

Holotype: TL 4.9 mm, TL-H 4.3 mm, MW 2.2 mm, TL/MW 2.23; PL 0.7 mm, PW 1.95 mm, PL/PW 0.36; DBE 0.85 mm, DBE/PW 0.44.

Colouration: Dorsally piceous, with reddish yellow head, pronotal sides, and two basal and one apical spot on elytron (Fig. 45 ).

Head yellowish red to reddish brown, darker narrowly behind eyes. Pronotum reddish brown to dark brown on disc and paler towards sides, yellowish red to reddish brown on them. Sometimes only anterior and posterior margins medially dark. Elytron dark brown to piceous, with two yellow to reddish brown spots on elytral base: one, larger, between striae 2 and 4 and second, smaller, between striae 4 and 6; sometimes these spots distinct, sometimes vague, sometimes completely reduced, seldom confluent; elytron with more or less distinct elongate apical spot, seldom absent. Scutellum reddish brown to piceous. Antennae, other head appendages, and legs proximally yellow; legs darker distally, yellowish red, especially metalegs. Venter yellow, with paler prosternum. Teneral beetles paler.

Surface sculpture: Elytron with six complete dorsal striae; submarginal stria present: 6+1 (Fig. 45 ).

Head without strioles, with sparse punctation (spaces between punctures 1-4 × size of punctures); punctures relatively fine (diameter of punctures usually 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 strong. Pronotum usually with several strioles laterally or only in posterolateral angles; with fine longitudinal wrinkles at posterior margin; pronotal punctation finer than on head; setigerous punctures form a row along pronotal margins, absent in posterior middle; disc of pronotum with indistinct longitudinal median scratch. Pronotum with distinct microreticulation, sometimes finer. Elytron with 6 dorsal striae; striae 1-4 and 6 complete, stria 5 usually shortly reduced basally, stria 1 very seldom shortly reduced basally; submarginal striae present. Elytron with distinct punctation and microreticulation, microreticulation sometimes finer. 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 numerous, finely 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 fine punctation that sparser medially and forms a dense, rugose lateral area at each side.

Structures: Head broad. Pronotum short and broad. Base of prosternum broadly rounded anteriorly, slightly convex medially; blade of prosternal process small, convex in middle.

Male: Protibia straight, not modified. Proclaws simple, subequal in length: anterior claw very slightly shorter than posterior one. Median lobe of aedeagus with two lobes of dorsal sclerite rather narrow; left dorsal lobe distinctly shorter that right one, with weak, long lateral crest and apex evenly curved downwards and to left, dorsally with distinct denticulation (spinulae) visible also in lateral left view; right dorsal lobe with small, indistinct, elongate median impression and modified apex: relatively large, slightly swollen, broadly rounded; left lobe of ventral sclerite with its sclerotised area large, rounded apically, shorter than right ventral and dorsal lobes and slightly more than 1/2 length of left dorsal lobe. Paramere with setae not clearly divided into distal and proximal, especially in left paramere; more distally situated setae slightly denser and longer than more proximal ones, with several the most proximal setae standing separately (Fig. 49 ).

Female: As male.

Variability.

There is a variation in the colouration, elytral striolation, dorsal microreticulation described above.

Affinities.

In general shape of median lobe, especially in shape of the sclerotised area of left ventral lobe and in shape of the lateral crest of the left dorsal lobe, the species is similar to A. testegensis sp. nov., A. manokwariensis sp. nov., and A. wanggarensis sp. nov. The species can be distinguished from them by its small, elongate habitus, elytron colouration, 6+1 elytral striae and shape of the median lobe; see more under the other species descriptions. Austrelatus testegensis sp. nov. is the most similar in the shape of median lobe sclerites to A. fakfak sp. nov.

Etymology.

The species is named for its Type locality. The name is a noun in the nominative standing in apposition.

Distribution.

New Guinean endemic. Indonesia: West Papua: Fakfak and Kaimana regencies (Fig. 83 ).

Habitat.

All seven specimens sampled in 1991 near Fakfak were collected in a shaded and water-filled tree hollow in primary lowland rainforest.

Figures

Figure 49. Austrelatus fakfak 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.