Copelatus portior Guignot, 1956

Hajek, Jiri, Shaverdo, Helena, Hendrich, Lars & Balke, Michael, 2021, A review of Copelatus diving beetles from the Solomon Islands, reporting the discovery of six new species (Coleoptera, Dytiscidae, Copelatinae), ZooKeys 1023, pp. 81-118 : 81

Copelatus portior Guignot, 1956 Figures 5-6 , 19

Copelatus portior Guignot, 1956: 53 (type locality: "New Hebrides [ Vanuatu], Malekula Island").

Copelatus divisus Watts, 1978: 122 ("Seleo, Berlinhafen" [ Papua New Guinea, Sandaun Province, Seleo Island); synonymy by Hendrich et al. (2019).

Material examined.

Guadalcanal : 1 ♂, Honiara, M.V. light, 8.-12.ix.1953 , J.D. Bradley leg.; 1 ♂, Honiara, Kukum , 1962, P.J.M. Greenslade leg. ; 1 ♀, same data, but 19.v.1962 ; 1 ♂, same data, but 20.v.1963 ; 1♂, same data, but, 2.iii.1965 ; 1 ♂, 1 ♀, same data, but 12.v.1966 (all NHMUK) ; 1 ♂, 1 ♀, Mt. Austine, Barana vill. env., 09°28.0'S, 159°58.4'E, 280 m, 23.xi.-8.xii.2013 , J. Hájek leg. ( NMPC, ZSMG).

Ontong Java: 1 ♂, 1 ♀, Keila, 31.i.1955, E.S. Brown leg. ( NHMUK) ; 1 ♀, Leuaniua, 27.i.1955, E.S. Brown leg. ( NHMUK) .

Diagnosis.

For complete description, see Hendrich et al. (2019). Medium sized (TL: 5.0- 5.7 mm), oblong-oval species. Species variable in elytral colouration: elytra from almost uniformly dark brown to black with only base and lateral sides yellowish, to almost yellowish-orange coloured with dark stripes along elytral striae (Fig. 5 ). Elytron with well-impressed six discal striae and a submarginal stria. Female dimorphic; striolate form with dorsal surface almost black, matt and with coarse microreticulation and numerous strioles on elytra and pronotum (Fig. 6 ). Median lobe in lateral view sickle-shaped; broad and subparallel in basal two thirds, thin and regularly curved in apical third; a distinct hammer-like process present in two thirds on ventral side (Fig. 19 ). Parameres broad, “D” -shaped; apical lobes moderately long, club-shaped.

Distribution.

The species is originally described from northern Papua New Guinea and Vanuatu. It is widely distributed in the Australasian Region: from Lesser Sunda Islands, through New Guinea, northern Australia, and Solomon Islands to Vanuatu. First record from the Solomon Islands.

Habitat.

Two specimens from Barana were recently collected in a streamlet flowing through secondary forest and gardens near the village; both of them were found in calm water with decaying leaves on the bottom (Fig. 26 ).

Figures

Figure 19. Male genitalia of Copelatus portior Guignot, 1956 (Australia) A median lobe in lateral view, right side B median lobe in lateral view, left side C median lobe in ventral view D left paramere in external view. Scale bar: 0.5 mm.

Figures 5, 6. Habitus of Copelatus 5 C. portior Guignot, 1956 (male, Guadalcanal; TL: 5.2 mm) 6 C. portior (striolate female, Papua; TL: 4.7 mm).

Figures 26 - 28. Habitats of Copelatus in Guadalcanal 26 temporary forest stream near Barana village 27 shaded pool on the same stream 28 small temporary puddles in a gorge along the road from Barana to Lungga river.