Actinopteri (ray-finned fishes) > Scombriformes
(Mackerels) > Gempylidae
Etymology: Tongaichthys: From the Tonga island in the Pacific ocean + Greek, ichthys = fish.
Environment: milieu / climate zone / depth range / distribution range
Marine; bathypelagic; depth range 288 - 312 m (Ref. 6181). Deep-water; 12°S - 27°S, 144°E - 174°W (Ref. 6181)
Pacific Ocean: Several specimens (38 individuals) were reported from the Tonga Ridge; around Fiji; 1 specimen from off Flinders Reef, Queensland (17°33'S, 149°46'E, CSIRO no. H1185-01).
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 30.0 cm SL male/unsexed; (Ref. 9784)
Probably mesopelagic or mesobenthopelagic (Ref. 6181).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Nakamura, I. and N.V. Parin, 1993. FAO Species Catalogue. Vol. 15. Snake mackerels and cutlassfishes of the world (families Gempylidae and Trichiuridae). An annotated and illustrated catalogue of the snake mackerels, snoeks, escolars, gemfishes, sackfishes, domine, oilfish, cutlassfishes,. scabbardfishes, hairtails, and frostfishes known to date. FAO Fish. Synop. 125(15):136 p. (Ref. 6181)
IUCN Red List Status (Ref. 125652)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningSpawning aggregationFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Preferred temperature (Ref. 123201
): 4.6 - 9.4, mean 6.1 °C (based on 78 cells).
Phylogenetic diversity index (Ref. 82804
= 1.0000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01072 (0.00446 - 0.02572), b=3.01 (2.80 - 3.22), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic level (Ref. 69278
): 3.9 ±0.6 se; based on size and trophs of closest relatives
Resilience (Ref. 120179
): Medium, minimum population doubling time 1.4 - 4.4 years (Assuming tmax>3).
Fishing Vulnerability (Ref. 59153
): Low to moderate vulnerability (27 of 100).