Description

Dorsal soft rays (total): 6 - 7; Anal soft rays: 15 - 17; Vertebrae: 27 - 29. Oryzias songkhramensis is distinguished from all other congeners by possessing the following combination of characters: anal-fin rays 15 - 16 (modally 16), bony contact organs on the anal-fin rays in males; a relatively anterior dorsal fin origin, opposite anal fin 13 - 14 (modally 14); vertebrae 27 - 29 (modally 28); fourth vertebra without neural prezygapophysis; scale relatively large, cycloid; 26 - 29 (modally 27) in a lateral series, predorsal scale 19 - 21 (modally 21); snout length shorter than eye diameter, snout length 12.9 - 31.2% (mean 21.7%) of HL; eye diameter 35.2 - 53.4% (mean 43.2%) of HL; a black spot at the base of pectoral fin, pectoral fin length 13.1 - 24.9% (mean 19.7%) of SL; length of anal fin base 19.4 - 30.0% (mean 25.6%) of SL; caudal peduncle length 11.3 - 20.3% (mean 16.7%) of SL; caudal fin slightly, rounded, length 3.6 - 3.8 (mean 3.7) in SL, black and pale yellow marginal bands on the dorsal and ventral portions of the caudal fin (Ref. 84389).

Common Names

No common names available.

Taxonomic Hierarchy

Kingdom: Animalia

Phylum: Chordata

Class: Teleostei

Order: Beloniformes

Family: Adrianichthyidae

Genus: Oryzias

Species: Oryzias songkhramensis Magtoon, 2010

Climate Zone

Location

Biology

The species was collected in clear water from ditches and paddy fields by dip nets in the Songkhram and Mekong River basins. The area of collection is a small ditch, 3-6 m wide and 0.5 to 2 m deep, Substrate ranges from sand to detritus or mud. Associated species include Trichogaster trichopterus, Trichopsis vittatus, Rasbora rubrodorsalis, Channa striata and Machrobrachium lanchesteri; aquatic plants Nymphaea lotus, Jussiaea repens and Hydrilla verticillata. Water quality in the area: 27.5-28.7 ºC, conductivity 41.5-124.4 μm/l, dissolved oxygen 2.05-3.97 mg/l, pH 7.1-7.9 and salinity 0.1 ppt (Ref. 84389).

Habitat

pelagic