Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Beloniformes
(Needle fishes) > Adrianichthyidae
(Ricefishes) > Oryziinae
Etymology: Oryzias: Greek, oryza = rice; because of the habitat used by this fish (Ref. 45335); sakaizumii: Named for Dr. Mitsuru Sakaizumi, a molecular geneticist at Niigata University, who pioneered in and contributed to the field of molecular phylogenetic study of Japanese ricefishes.
Environment: milieu / climate zone / depth range / distribution range
Freshwater; pelagic. Tropical; 36°N - 35°N, 136°E - 137°E
Asia: freshwaters along the Sea of Japan coast in the northern half of Honshu, from the Pacific coast of Momoishi, Aomori Pref. to Hyogo Pref. around Tango, Tajima district that distributional western limit is Hamasaka.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 3.7 cm SL male/unsexed; (Ref. 89067)
Morphology | Morphometrics
Oryzias sakaizumii is distinguished from all other congeners including O. latipes that are distributed throughout east Asia by the following combination of characters: distribution of melanophores, dense network of melanophores along each scale margin on the body surface in both sexes; depth of notch in membrane between dorsal-fin rays 5 and 6 less than half the length of rays in males; distinctive irregular black spots on the posterior portion of body lateral; and several silvery scales in patches on the posterior portion of the body (Ref. 89067).
Occurs in ponds, marshes, and streams, such as irrigation canals amid paddy fields in flat alluvial lowlands. Well adapted to aquatic life on temporary floodplain wetlands (Ref. 89067).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Asai, T., H. Senou and K. Hosoya, 2012. Oryzias sakaizumii, a new ricefish from northern Japan (Teleostei: Adrianichthyidae). Ichthyol. Explor. Freshwat. 22(4):289-299. (Ref. 89067)
IUCN Red List Status (Ref. 115185)
CITES (Ref. 115941)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates of some properties based on models
Phylogenetic diversity index (Ref. 82805
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00479 (0.00186 - 0.01229), b=3.13 (2.91 - 3.35), in cm Total Length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic Level (Ref. 69278
): 3.4 ±0.4 se; Based on size and trophs of closest relatives
Resilience (Ref. 69278
): High, minimum population doubling time less than 15 months ().
Vulnerability (Ref. 59153
): Low vulnerability (10 of 100) .