Tuesday, July 19, 2011

[Ichthyology • 2011] Oryzias woworae • Remarkably Colorful, Small Ricefish from southeastern Sulawesi, Indonesia


Fig. 1. (upper) Live adult male Oryzias woworae photographed in the field
Fig. 2. (lower) Live adult female Oryzias woworae, center, with two adult males,
photographed in the field just after collection. Original photograph has been reversed.


Oryzias woworae • Daisy’s Ricefish

Oryzias woworae, a new species of ricefish, is described from a freshwater habitat on Muna Island off the southeastern coast of the main island of Sulawesi, Indonesia. The new species is distinguished from all other known ricefishes by a remarkable color pattern of both sexes in life: the ventral surface of head and body anterior to the pelvic fins, dorsal portion of pectoral fins, dorsal-fin base, posterior portion of anal-fin base, caudal peduncle, and dorsal and ventral portions of caudal fin are brilliant red; the midlateral scales from just posterior to the eye to the caudal-fin base and the body scales anterior to the anal fin and ventral to midlateral scales are steel blue; the blue coloration is most prominent in adult males. Oryzias woworae, the smallest known ricefish from Sulawesi, is hypothesized to be a member of an unnamed clade of ricefishes diagnosed by a truncate, rather than lunate or emarginate, caudal fin. Description of O. woworae brings the recognized number of species in the beloniform family Adrianichthyidae to 29, 13 of which are endemic to Sulawesi. Ricefishes, in particular the new species, may serve as icons to generate interest in conservation of the endemic freshwater biota of Sulawesi.

Fig. 2. Live adult female Oryzias woworae, center, with two adult males, photographed in the field just after collection. Original photograph has been reversed.

Holotype.—MZB 15398 (Fig. 3), male, 25.0 mm SL, Indonesia, Sulawesi Tenggara, Muna Island (Fig. 4), Regency of Muna, District Parigi, Village Wakumoro, Mata air Fotuno (Fotuno oe; Fig. 5), 5u04939.70S, 122u30925.70E, 13 September 2007, D. Wowor.

Etymology.— The trivial name woworae honors Daisy Wowor, a systematic carcinologist from the Museum Zoologicum Bogoriense, who collected specimens of the new species and had the foresight to take color photographs of the fish alive.

Distribution and habitat.— The single known collection of O. woworae was from the type locality, a freshwater stream with a canopy cover of about 80 percent and substrate of mud and sand with leaf litter (Fig. 5).


Fig. 3. Oryzias woworae, new species, MZB 15398, preserved holotype, male, 25.0 mm SL.

Fig. 4. Outline map of Sulawesi with southeastern region (in small box) expanded in larger box. Star indicates type locality of Oryzias woworae, new species.

Oryzias woworae, new species, Mata air Fotuno (Fotuno oe), a freshwater stream running through the Wakumoro Village, Parigi District, Muna Island.

A New, Remarkably Colorful, Small Ricefish of the Genus Oryzias (Beloniformes, Adrianichthyidae) from Sulawesi, Indonesia: http://si-pddr.si.edu/jspui/bitstream/10088/9776/1/vz_Parenti_and_Hadiaty_2010.pdf