Melanotaenia susii
Species Summary
Melanotaenia susii is one of eight closely related rainbowfishes from the Birds Head region of West Papua, Indonesia, described together in 2015 on the basis of combined evidence: a cytochrome oxidase I (COI) gene phylogeny, genotyping at 12 microsatellite loci, and diagnostic morphological characters. The approach revealed a level of cryptic diversity in the region well beyond what traditional morphological survey alone had detected. At 114.1 mm SL its holotype is the largest type specimen among the eight species described in the same paper. It belongs to the ‘Central Ayamaru Plateau’ cluster together with M. klasioensis and M. longispina.
Etymology
The species is named for Susi Creek, the type locality.
Etymology compiled from C. Scharpf (2023), “Fishes of Sahul: An Etymological Survey (Part 6), the rainbowfishes (continued)”, Fishes of Sahul 37(1): 2006–2022, and etyfish.org.
Distribution & Habitat
Melanotaenia susii is known only from Susi Creek, a karst resurgence less than 3 m wide on the road between Sorong and Ajamaru, running only a few kilometres before disappearing into a subterranean outlet. The type locality is clear, shallow and slow-flowing, over limestone boulders and a muddy bottom with abundant dead tree branches, bordered by dense forest.
Description & Comparison with Similar Species
Live males are compressed-bodied with a long snout, olive-green to near-black dorsally with mauve reflections on the upper flank and reddish tones below, a discontinuous dark green-olive mid-lateral stripe, and two to five vertical bars crossing the full depth of the anterior body — a pattern absent in its close relatives M. klasioensis and M. longispina. The dorsal fins carry a marked red margin, the pelvic fin is reddish-black, and the anal fin is dark with blue rays and a reddish posterior tip. From M. klasioensis it is further told apart by more lateral scales, a longer snout, a narrower interorbital and body, and a longer predorsal length; from M. longispina, by the presence of a dorsal margin stripe and shorter fin spines.
Account compiled for Home of the Rainbowfish from M. F. I. Nugraha, Kadarusman, N. Hubert, J.-C. Avarre, R. K. Hadiaty, J. Slembrouck, O. Carman, Sudarto, R. Ogistira & L. Pouyaud (2015), “Eight new species of Rainbowfishes (Melanotaeniidae) from the Birds Head Region, West Papua, Indonesia”, Cybium 39(2): 99–130.
References
- Nugraha M.F.I., Kadarusman, N. Hubert, J.C. Avarre, R.K. Hadiaty, J. Slembrouck, O. Carman, Sudarto, R. Ogistira and L. Pouyaud (2015) Eight new species of Rainbowfishes (Melanotaeniidae) from the Birds Head Region, West Papua, Indonesia. Cybium 39(2): 99-130.