Actinopteri (ray-finned fishes) > Beloniformes
(Needle fishes) > Belonidae
Etymology: Tylosurus: Greek, tylos = callus + Greek, oura = tail (Ref. 45335). More on author: Bleeker.
Considered mostly as a subspecies in the literature. Therefore the upraise at species rank here is considered as a provisionally accepted name, until more works are conducted on T. acus susbepcies to fix their status.
Environment: milieu / climate zone / depth range / distribution range
Marine; freshwater; brackish; reef-associated; oceanodromous (Ref. 51243); depth range - 1 m (Ref. 58302), usually - m (Ref. ). Tropical; 0°C - ; 32°N - 28°S
Indo-Pacific: East Africa (Ref. 3130) to the central and south Pacific. Eastern Central Pacific: oceanic islands such as the Revillagigedo, Clipperton and Cocos (Ref. 9279).
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 100.0 cm TL male/unsexed; (Ref. 9137); common length : 115 cm TL male/unsexed; (Ref. 5450)
soft rays: 22 - 24;
Vertebrae: 90 - 95. Anterior part of dorsal fin with a low lobe, contained 10.5-13.3 times in body length; a distinct black lateral keel on caudal peduncle; caudal fin deeply forked. Juveniles have an elevated black lobe in the posterior part of the dorsal fin (Ref. 9682). Longer jaws with more numerous teeth and narrower caudal lobes than T. crocodilus (Ref. 37816).
Found in offshore and coastal waters. Feeds mainly on small fishes. Marketed mostly fresh. The flesh is of good quality (Ref. 9682). Oviparous (Ref. 205). Eggs may be found attached to objects in the water by tendrils on the egg's surface (Ref. 205).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Collette, B.B., 1984. Belonidae. In W. Fischer and G. Bianchi (eds.) FAO species identification sheets for fishery purposes. Western Indian Ocean (Fishing Area 51), Volume 1. FAO, Rome. (Ref. 3130)
IUCN Red List Status (Ref. 124695)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningSpawning aggregationFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Preferred temperature (Ref. 115969
): 28.2 - 29.3, mean 28.8 °C (based on 979 cells).
Phylogenetic diversity index (Ref. 82805
= No PD50 data [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00126 (0.00056 - 0.00281), b=3.11 (2.93 - 3.29), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic level (Ref. 69278
): 4.3 ±0.76 se; based on food items.
Resilience (Ref. 120179
): Medium, minimum population doubling time 1.4 - 4.4 years (Preliminary K or Fecundity.).
Vulnerability (Ref. 59153
): Moderate to high vulnerability (51 of 100) .
Nutrients (Ref. 124155
): Calcium = 54.3 [22.3, 139.0] mg/100g ; Iron = 0.631 [0.314, 1.279] mg/100g ; Protein = 16.2 [13.1, 19.3] % ; Omega3 = 0.271 [0.099, 0.803] g/100g ; Selenium = 46.9 [18.4, 120.8] μg/100g ; VitaminA = 530 [59, 2,703] μg/100g ; Zinc = 1.01 [0.61, 1.69] mg/100g (wet weight);