Elasmobranchii (sharks and rays) > Torpediniformes
(Electric rays) > Platyrhinidae
Etymology: Platyrhina: Greek, platys = flat + Greek, rhinos = nose. It is the same voice used for the Mammalian division made in Primates (Ref. 45335); hyugaensis: Named for the belief that it is endemic and common to the Hyuga Nada Sea.
Environment: milieu / climate zone / depth range / distribution range
Marine; pelagic-neritic; depth range 1 - 50 m (Ref. 86259). Temperate; 30°N - 34°N, 127°E - 140°E (Ref. 114953)
North-West Pacific: endemic to southern Japan.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 43.1 cm TL (female)
Morphology | Morphometrics
This species is distinguished from its congeners by the following set of characters: a row of thorns (strongly hooked) on mid-dorsum of tail; a pair of thorns on anterior part of scapular region (apparent to touch in smallest specimen; 161 mm TL); thorns on orbital, nape and scapular regions not encircled by light yellow or white pigment; dorsal surface covered with minute dermal denticles of uniform size and shape, no obvious larger dermal denticles (smooth to touch) (Ref. 86259).
A benthic ray species that is narrow-ranging (Ref. 114953). According to local divers in Miyazaki, this species often occurs on very shallow sandy bottoms, at depths as shallow as ca. 1 m, in the summer season off the Nichinan Coast, Miyazaki. It is frequently captured by set net within a depth of ca. 50 m from early spring (March) to autumn (November). It was observed by a local fisherman and a fish merchant (pers.comm.), that this species was not included in almost daily set net catches (depth ca. 8-50 m) from November to March in 2007-2008 in northern Miyazaki (Kadokawa Bay) and southern Miyazaki (Meitsu, Nichinan Coast) which indicate that the species avoids lower sea temperatures in the winter season (Ref. 86259). Males mature from ca. 20 cm TL (Ref. 114953).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Iwatsuki, Y., K. Miyamoto, K. Nakaya and J. Zhang, 2011. A review of the genus Platyrhina (Chondrichthys: Platyrhinidae) from the northwestern Pacific, with descriptions of two new species. Zootaxa 2738:26-40. (Ref. 86259)
IUCN Red List Status (Ref. 123251)
CITES (Ref. 123416)
Threat to humans
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82805
= 0.6250 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01000 (0.00244 - 0.04107), b=3.04 (2.81 - 3.27), in cm total length, based on all LWR estimates for this body shape (Ref. 93245
Trophic level (Ref. 69278
): 3.4 ±0.4 se; based on size and trophs of closest relatives
Vulnerability (Ref. 59153
): Low to moderate vulnerability (33 of 100) .