Sunday, February 11, 2024


Classification of the oarfish:

Phylum Chordata

Class Actinopterygii

Order Lampriformes

Family Regalecidae

Genus Regalecus

(Two) Species: glesne Ascaniusm 1772 and russelii (Cuvier, 1816)

Both species are circum-global, but only R. russelii has been found in California (Feeney and Lea, 2018).

The living oarfish is a ray-finned fish with a ribbon-like shape that can be up to 36 feet long (11 m). It has a circum-global distribution, except for polar regions. It is most commonly found in the tropics to middle latitudes. It lives at depths of 3,200 feet (1,000 m) but can occur in shallower water (nearshore to 200 m depths). It is rarely been seen in the vicinity of beaches, unless it has been washed up. In such cases, even in southern California, it creates great attention. Typically, in such cases, pictures will be taken with 15 or 20 people holding up a dead oarfish. 

This actual specimen of an oarfish (Regalecus sp.) is on display in an exhibit at the Natural History Museum of Los Angeles County (LACM). This specimen is 14.5 feet long. It was alive when it swam into Big Fisherman Cove at Catalina Island in 2006. Researchers photographed it as they swam aside it, before it died of natural causes. Image courtesy of Lindsey T. Groves, Collections Manager of Malacology at LACM. 

My sketch of a living oarfish.

In forklore, oarfish have been associated with “sea serpents” and forbearers of doomsday calamities (e.g., earthquakes and other catastrophic changes).

The oarfish body is narrow laterally, with a dorsal fin (typically reddish) along the entire length. It swims, in an undulating manner, by means of its dorsal fin, but it and can also swim in a vertical position. Its head is small with no teeth (it swallows small-sized marine crustaceans, called krill). Also the oarfish has no swim bladder. 

It has a small head with no teeth, but it eats krill. 

The ancestor of the extant giant oarfish might have been stickleback fish, which possibly date back to the Early Cretaceous (early Cenomanian Stage) in Italy (see (Sorbini, 1966). It is also interesting to note that stickleback fish today are confined to the Northern Hemisphere where they can live in oceans, brackish, or fresh water.

References Cited and/or used:

Feeney, R.F. and R.N. Lea. 2018. California records of the oarfish, Regalecus russelii (Cuvier, 1816) (Actinopterygii: Regalecidae). Bulletin of Southern California Academy of Sciences 117(3):169–179. (pdf available online, for free).

Sorbini, L. 1996. New superfamily and three new families of tetraodoniform fishes from the Upper Cretaceous: the earliest and most morphologically primitive Pectognatus. Smithsonian Contributions to Paleontology 82:1–59. (pdf available online, for free).

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