Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Gadiformes
(Cods) > Macrouridae
(Grenadiers or rattails) > Macrourinae
Etymology: Hymenocephalus: Named for its transparent membrane-like head covering (‘‘hymen head’’) and fragile nature of head bones (Ref. 100825); yamasakiorum: Named for Ms. Yasuko Yamasaki and her family; a fishing trawler operator in Tosa Bay and adjacent waters and provider of a large number of fish specimens to the BSKU collection.
Environment: milieu / climate zone / depth range / distribution range
Marine; bathydemersal; depth range 380 - 420 m (Ref. 100825). Temperate
Countries | FAO areas | Ecosystems | Occurrences | Point map | Introductions | Faunafri
Northwest Pacific: Japan.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 15.1 cm TL male/unsexed; (Ref. 100825)
Morphology | Morphometrics
This species is distinguished by the following characters: 9 pelvic-fin rays; chin barbel 55 % HL, its tip extending beyond vertical through hind margin of orbit when laid back; moderately high snout, not depressed, length 28 % HL; orbit diameter 33 % HL; interorbital width 24 % HL; preopercular supporter broad, short (5 % HL); D1 II,10; pectoral-fin rays i16-i17; gill rakers on first arch (outer/inner) 14/20, on second arch 20/19; pyloric caeca 15; when fresh the ventral two-thirds of head and body are silvery; dorsal half of posterior part of tail prominently dark; ventral half of tail completely immaculate; OL:OH = 1.15; ostial and caudal colliculi not fused; TCL:PCL = 2.3 (Ref. 100825).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Nakayama, N., H. Endo and W. Schwarzhans, 2015. A new grenadier of the genus Hymenocephalus from Tosa Bay, southern Japan (Actinopterygii: Gadiformes: Macrouridae). Ichthyol. Res. (Ref. 100825)
IUCN Red List Status (Ref. 115185)
CITES (Ref. 115941)
Threat to humans
CountriesFAO areasEcosystemsOccurrencesIntroductionsStocksEcologyDietFood itemsFood consumptionRation
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=0.00219 (0.00097 - 0.00495), b=3.17 (2.98 - 3.36), in cm Total Length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic Level (Ref. 69278
): 3.3 ±0.4 se; Based on size and trophs of closest relatives
Resilience (Ref. 69278
): High, minimum population doubling time less than 15 months (Preliminary K or Fecundity.).
Vulnerability (Ref. 59153
): Low to moderate vulnerability (25 of 100) .