Elasmobranchii (sharks and rays) > Rhinopristiformes
(Shovelnose rays) > Rhinidae
Etymology: Rhynchobatus: Greek, rhingchos = snout + Greek, batis, -idos = a sting ray (Raja sp.) (Ref. 45335); mononoke: Name 'mononoke' means 'specter' in Japanese, due to the ventral surface of specimens appearing like a traditional Japanese specter, wearing a triangular white hat (crown) on its forehead; noun in apposition..
Environment: milieu / climate zone / depth range / distribution range
Marine; pelagic-neritic; depth range 15 - 136 m (Ref. 123186). Subtropical
Northwest Pacific: southern Japan.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 130 cm TL male/unsexed; (Ref. 123186); 200.0 cm TL (female)
Morphology | Morphometrics
This species is distinguished by the following set of characters: snout obtusely wedge shaped, angle ca. 52-57°; preoral length 17.4-17.9% TL, prespiracular length 19.3-19.5%; interdorsal space 16.7-17.9%; total pectoral-fn radials 54-56; total free vertebral centra 136-144; tooth rows on upper jaw ca. 54-66; no spines on snout; outer fold on posterior margin of spiracle is more pronounced than inner fold; pre-first dorsal-fin length 46.4-48.6%; apex of dorsal fins bluntly rounded; origin of first dorsal fn about level with the pelvic-fin origin; middle of pectoral disc with a spiracle-sized black blotch followed by a single white spot (rarely absent) posterodorsally; distal region of pectoral disc to mid-dorsal area without distinct white spots; a single blotch below the eye is usually absent; anterior half of undersurface covered with a rounded black blotch; near the snout tip, a pair of small distinct black spots (Ref. 123186).
This species is currently known only from nearshore to offshore waters and have been collected by set net from 15-35 m, but was also reported to have been taken at 135 m by bottom trawl. Based on photos of landed individuals, this species probably attains close to 3 m TL. The captive female individual held for at least 15 years in the Kagoshima City Aquarium reached to 2 m TL. This wedgefish is occasionally landed at fish markets in Kagoshima Prefecture and used for culinary purpose. Reported catches of the species were very rare in the East China Sea and is apparently restricted distribution and increasing rarity indicate that the species should immediately be included in the IUCN Red List CR “Critically Endangered” category, together with other congeners (Ref. 123186).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Koeda, K., M. Itou, M. Yamada and H. Motomura, 2020. Rhynchobatus mononoke, a new species of wedgefish (Rhinopristiformes: Rhinidae) from Japan, with comments on Rhynchobatus laevis (Bloch and Schneider 1801). Ichthyol. Res. 68:223-238. (Ref. 123186)
IUCN Red List Status (Ref. 126983)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningSpawning aggregationFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82804
= No PD50 data [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00372 (0.00166 - 0.00830), b=3.11 (2.90 - 3.32), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic level (Ref. 69278
): 3.6 ±0.6 se; based on size and trophs of closest relatives
Fishing Vulnerability (Ref. 59153
): Very high vulnerability (90 of 100).