Pacific Shortfin Eel, Anguilla obscura Günther 1872

Other Names: Pacific Shortfinned Eel, Pacific Short-finned Eel, South Pacific Eel

Summary:

The Pacific Shortfin Eel is uniform silver or yellowish to dark brown, becoming paler below. The dorsal fin originates before the anus, just in front of, or level with the anal fin origin, and the jaws reach beyond the eye.

Cite this page as:

Gomon, M.F. & Bray, D.J. 2021, Anguilla obscura in Fishes of Australia, accessed 08 Dec 2024, https://fishesofaustralia.net.au/home/species/1425

Pacific Shortfin Eel, Anguilla obscura Günther 1872

More Info

Distribution	Coastal drainages from the Watson River, NE of Aurukun, Gulf of Carpentaria, to Fraser Island, Queensland. Elsewhere the species occurs in the tropical, south-west Pacific: Indonesia (Papua), Papua New Guinea, Solomon Islands, New Caledonia, Cook Islands, Fiji, Samoa, Tonga, Vanuatu, French Polynesia. Inhabits freshwater streams, lakes and swamps, favoring coastal lagoons and the lower reaches of rivers. The species is catadromous, and adults migrate from freshwater to the sea to spawn in oceanic waters.
Features	Pectoral fin 14-20; Vertebrae 101-107. Body, elongate, tubular, snake-like; head moderately small (10-14% SL); eyes dorsally positioned in large adults; mouth moderately large, horizontal, reaching to below posterior edge of eyes; teeth fine, broad band on each side of both jaws and on vomer, vomerine patch much shorter than bands laterally in jaws; gill openings small, just in front of lower half of pectoral fin bases. Scales tiny, elongate, embedded, arranged in a basket work pattern; lateral line straight, not associated with scales. Dorsal, anal and caudal fins confluent; dorsal fin origin before the anus, just in front of, or level with anal fin; ventral fins absent; pectoral fin small and fan-like.
Size	Reportedly reaches a total length of 120 cm, but more commonly grows to about 60 cm.
Colour	Varying from silver or yellowish to dark brown on the dorsal and lateral surfaces, becoming paler ventrally.
Feeding	Feeds mostly on fishes, molluscs and crustaceans.
Biology	Adults may remain in freshwater environments for 20 years or more before migrating to the sea to spawn. Pacific Shortfin Eels are thought to spawn east of Tahiti, and the larvae are then taken westwards and south via the South Equatorial Current. After spawning, the small, pelagic eggs float towards the surface, where they hatch into leptocephalus larvae. Leptocephali are transparent, elongate, compressed and leaf-like. Leptocephali are believed to be passively transported to the continental shelf by oceanic currents before metamorphosis to the glass eel stage. During metamorphosis to the glass eel stage, the body shortens and becomes narrower, and the teeth are lost. Glass eels move shoreward into estuaries and rivers. While in the estuaries, glass eels acclimate to reduced salinities and develop rapidly into fully pigmented elvers with teeth and fully developed stomachs. This is followed by a secondary upstream migration into freshwater.
Fisheries	The species is taken in subsistence fisheries in the Southwest Pacific.
Conservation
Species Citation	Anguilla obscura Günther 1872, Proc. Zool. Soc. Lond. 1871(3): 673. Type locality: Kanathea, Fiji Islands.
Author	Gomon, M.F. & Bray, D.J. 2021
Resources	Atlas of Living Australia Australian Faunal Directory Catalog of Fishes

Pacific Shortfin Eel, Anguilla obscura Günther 1872

References

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