Two new species of rainbowfishes have been named from New Guinea in the latest issue of Aqua, International Journal of Ichthyology.
Named Melanotaenia ammeri and M. kokasensis by Gerald Allen, Peter Unmack and Renny Hadiaty, the two species are known from the southwestern Birds Head region of western New Guinea (Papua Barat Province, Indonesia).
Melanotaenia ammeri is named after Max Ammer and is distinguished from congeners by the following combination of characters: IV"VI,12"15 dorsal rays; I,20"25 anal rays; 12"14 pectoral rays; 34-36 lateral scales; 17"19 predorsal scales; 16"18 gill rakers on first arch; colour in life generally bluish dorsally with series of alternating mauve to blue-grey and pale yellow stripes (one per scale row) on side of body, midlateral blue stripe usually much darker than others; median fins generally yellow, brighter in adult males.
The type locality of this species is a narrow (to about 2-3 m wide), relatively shallow (to about 0.5 m) stream with gradual gradients flowing through second growth forest, about one kilometer upstream from the sea.
The type specimens were collected over sand and gravel bottoms with substantial leaf litter and dead tree branches.
Melanotaenia kokasensis is distinguished from congeners in having a combination of: IV"V,11"14 dorsal rays; I,21"24 anal rays; 13"15 pectoral rays; 35-37 lateral scales; 16"18 predorsal scales; 16"19 gill rakers on first arch; colour of adult male in life generally pale blue grey with blackish midlateral stripe at level of upper pectoral-fin base (sometimes faint on anterior part of body); narrow orange stripe between each scale row on upper half of body; broad, horizontally bluish streak immediately above abdomen; pelvic and anal fins pale yellowish, remaining fins mainly colourless or slightly grey except narrow white margin on second dorsal fin and narrow blackish dorsal and ventral margins on caudal fin.
This species is named after the village of Kokas, which is situated near the type locality and was collected in a small stream flowing along a limestone creek bed through primary forest.
The fish was located about one kilometre upstream, in a circular pool with an approximate diameter of 15-20 m and maximum depth of about 0.5 m.
For more information, see the paper: Allen, GR, PJ Unmack and RK Hadiaty (2008) - Two new species of rainbowfishes (Melanotaenia: Melanotaeniidae), from, western New Guinea (Papua Barat Province, Indonesia). Aqua, International Journal of Ichthyology 14, pp. 209"224.