Hound needlefish (Tylosurus crocodilus crocodilus)

Scientific name: Tylosurus crocodilus crocodilus P?ron & Lesueur, 1821

The Hound needlefish (Tylosurus crocodilus crocodilus) is a marine fish of the family Belonidae. In the aquarium it needs water at 26–29°C (79–84°F).

Hound needlefish care at a glance

Temperature: 26–29°C (79–84°F)

Biology

Dorsal spines (total): 0; Dorsal soft rays (total): 21-25; Anal spines: 0; Anal soft rays: 19 - 22; Vertebrae: 80 - 86. Back dark bluish, sides silvery, white ventrally. A distinct black lateral keel on caudal peduncle; caudal fin deeply forked. Juveniles (to 20 cm BL) have an elevated black lobe in the posterior part of the dorsal fin. Jaw teeth point anteriorly in juveniles (to 40 cm BL) but are straight at all sizes in other species of Tylosurus. Has a relatively stout, cylindrical body and a shorter head as compared to other needle fishes.

Source: FishBase, licensed CC BY-NC 4.0.

Species facts

Scientific name: Tylosurus crocodilus crocodilus
Family: Belonidae (Needlefishes)
Order: Beloniformes (Needle fishes)
Class: Actinopterygii (Ray-finned fishes)
Maximum length: 150
Common length: 90.0
Depth range: 0–13 m (0–43 ft)
Environment: Marine; reef-associated; oceanodromous; depth range 0 - 13 m
Climate: Tropical
Distribution: Indo-West Pacific: Red Sea and South Africa to French Polynesia, north to Japan, south to New South Wales, Australia. Replaced by Tylosurus crocodilus fodiator in the eastern Pacific. Western Atlantic: New Jersey, USA to Brazil. Eastern Atlantic: Fernando Poo, Cameroon, Liberia, and Ascension Island; from Senegal and Guinea; and Cape Verde. Recorded from the Mediterranean Sea.
Conservation status (IUCN): Not Evaluated
Threat to humans: Traumatogenic
Uses: Fisheries: commercial; gamefish: yes
Resilience: Medium, minimum population doubling time 1.4 - 4.4 years (Preliminary K or Fecundity.)

Sources

Taxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0.

Last updated 27 September 2026