Elasmobranchii (sharks and rays) > Myliobatiformes
(Stingrays) > Myliobatidae
(Eagle and manta rays) > Mobulinae
Etymology: japanica: Named for Japan.
Environment / Climate / Range
Marine; reef-associated, usually 0 - 200 m (Ref. 89423). Subtropical; 40°N - 30°S
Length at first maturity / Size / Weight / Age
Maturity: Lm ?, range 198 - 205 cm
Max length : 310 cm WD male/unsexed; (Ref. 50641); 240.0 cm WD (female); common length : 225 cm WD male/unsexed; (Ref. 9256)
Dark blue to black above, white below. Inner surface of cephalic fins silver grey with black tip, outer surface and side behind eye white (Ref. 11228). Shared characters between M. rancureli and Mobula japanica: teeth, placoid scales, and branchial filter morphologies, morphometrics, presence of tail spine, distinctive shape and coloration of dorsal fin, and general shape of body and coloration (Ref. 50641).
Indo-Pacific: off South Africa, the Arabian Sea eastward to the Hawaiian Islands and Polynesia. Eastern Pacific: on the continental coast. Eastern Atlantic: Côte d'Ivoire but may probably be more wide-ranging. This has to be critically compared with Mobula mobular of the Mediterranean Sea and nominally elsewhere in the North Atlantic.
Found inshore, possibly in oceanic waters (Ref. 9911). Pelagic (Ref. 58302). Occurs singly or in groups (Ref. 9911). Feeds mainly on euphausiids (mainly Nictiphanes simplex), and to a lesser extent on copepods and crustacean larvae. May also feed on small fishes. Ovoviviparous (Ref. 50449). Acoustic tracks record the species to spend time above the thermocline at night to feed on krill (H. Dewar, pers.comm. 05/2000). Very common by-catch of the gillnet fisheries targeting skpjack tuna (Katsuwonus pelamis). Utilized for its gill filter plates (very high value), meat, cartilage and skin (Ref.58048).
Exhibit ovoviparity (aplacental viviparity), with embryos feeding initially on yolk, then receiving additional nourishment from the mother by indirect absorption of uterine fluid enriched with mucus, fat or protein through specialised structures (Ref. 50449). With one in a litter (Ref. 12951). Size at birth 85-92 cm WD (Ref. 12951, Ref.58048).
Last, P.R. and J.D. Stevens, 1994. Sharks and rays of Australia. CSIRO, Australia. 513 p. (Ref. 6871)
IUCN Red List Status (Ref. 96402)
CITES (Ref. 94142)
Threat to humans
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates of some properties based on models
Phylogenetic diversity index (Ref. 82805
= 0.5020 [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), based on all LWR estimates (Ref. 93245
Trophic Level (Ref. 69278
): 3.4 ±0.43 se; Based on food items.
Resilience (Ref. 69278
): Very Low, minimum population doubling time more than 14 years (Fec=1).
Vulnerability (Ref. 59153
): High vulnerability (55 of 100) .