Exocelina manokwariensis nokensis, Shaverdo, Helena, Panjaitan, Rawati & Balke, Michael, 2016

Shaverdo, Helena, Panjaitan, Rawati & Balke, Michael, 2016, A new, widely distributed species of the Exocelinaekari-group from West Papua (Coleoptera, Dytiscidae, Copelatinae), ZooKeys 554, pp. 69-85 : 79-82

Taxon classification Animalia Coleoptera Dytiscidae

Exocelina manokwariensis nokensis ssp. n. Figs 7, 8

Exocelina undescribed sp. MB1275: Toussaint et al. 2014: Supplementary figs 1-4, tab. 2.

Type locality.

Indonesia: West Papua Province: Raja Ampat Regency, Waigeo Island, Waifoi, Mountain Nok, 00°05.08'S; 130°44.59'E.

Type material.

Holotype: male "Indonesia: Papua, Waigeo, Waifoi, Mt. Nok, 500m, 00.05.076S 130.44.586E (BH 11)" (MZB). Paratypes: 25 males, 39 females with the same labels as the holotype, one male additionally with a green label "M.Balke 1275" (MZB, NHMW, ZSM). 1 male "Indonesia: Papua, Waigeo, Waifoi, <50m, 00.06.088S 130.42.855E, Balke (BH 10)", "M.Balke 1274" [green] (ZSM). 23 males "N.DUTCH NEW GUINEA: Waigeu. Camp Nok. 2,500 ft. iv.1938. L.E.Cheesman. B.M.1938-593.", one of them additionally with labels "collection 28", "measured J.Parkin 78" (BMNH). 5 males "N.DUTCH NEW GUINEA: Waigeu.Camp 1.Mt.Nok. 2,500 ft. v.1938. L.E.Cheesman. B.M.1938-593." (BMNH).

Additional material.

27 females "N.DUTCH NEW GUINEA: Waigeu. Camp Nok. 2,500 ft. iv.1938. L.E.Cheesman. B.M.1938-593.", one of them additionally with labels "collection 27", "measured J.Parkin 76" (BMNH). 6 females "N.DUTCH NEW GUINEA: Waigeu.Camp 1.Mt.Nok. 2,500 ft. v.1938. L.E.Cheesman. B.M.1938-593." (BMNH). These females might belong to two species: Exocelina manokwariensis nokensis ssp. n. and Exocelina waigeoensis Shaverdo, Hendrich & Balke, 2012.

Description.

As nominative subspecies, except for the following characters.

Size: TL-H 3.1-3.6 mm, TL 3.45-4.0 mm, MW 1.65-1.9 mm; holotype: TL-H 3.4 mm, TL 3.75 mm, MW 1.8 mm (Fig. 7).

Surface sculpture: Dorsal microreticulation, especially on head and pronotum, slightly weaker.

Structures: Base of prosternum and neck of prosternal process with distinct ridge, less rounded, smooth or with few transverse lines anteriorly.

Male: Protarsomere 5 ventrally with anterior row of 9 and posterior row 4 short setae (Fig. 8B). Abdominal ventrite 6 with 3-6 lateral striae on each side. Median lobe slightly larger and somehow more slender. Its apex with relatively short tip and truncate margin almost straight in lateral view and asymmetric in ventral view (Fig. 8C, D). Subdistal part of paramere with less numerous, thick flattened setae (Fig. 8E).

Female: Antennae simple, abdominal ventrite 6 broadly rounded apically, without striae.

Comparation with the other subspecies and co-inhabiting species.

Although widely separated geographically, Exocelina manokwariensis nokensis ssp. n. is very similar to the nominative subspecies, from which can be separated by the larger and somehow more slender median lobe, less numerous flattened setae on the paramere, and its finer dorsal microreticulation. This subspecies was collected together with two other species of the Exocelina ekari -group: Exocelina evelyncheesmanae Shaverdo, Hendrich & Balke, 2012 and Exocelina waigeoensis Shaverdo, Hendrich & Balke, 2012; see descriptions and illustrations in Shaverdo et al. 2012. From the former (both males and females), it can be easily separated by its smaller size and distinctly modified male antennae (TL-H: 3.75-4.1 mm, MW: 1.9-2.2 mm and slightly modified male antennae: antennomeres 3-7 very slightly enlarged, antennomere 3 slightly more triangular than other antennomeres, in Exocelina evelyncheesmanae ). From the latter, males can be distinguished by their distinctly modified antennae and the shapes of the median lobes (slightly modified antennae and apex of the median lobe elongate in lateral view in Exocelina waigeoensis ).

Distribution.

Indonesia: West Papua Province: Raja Ampat Regency, Waigeo Island (Fig. 9).

Etymology.

The species is named after Nok Mountain, the type locality of the species. The name is an adjective in the nominative singular.

Ecology.

The species was collected in two localities on Nok Mountain together with Exocelina evelyncheesmanae and Exocelina waigeoensis and in one locality together with Exocelina evelyncheesmanae in ration ca. 1:1.