Monognathus
Monognathus, or onejaw, is the only genus of the family Monognathidae of deep-sea eels. The name comes from the Greek monos meaning “one” and gnathos meaning “jaw”, a reference to the large mouth in comparison with the rest of the fish, and also the absence of an upper jaw (maxilla and premaxilla bones are absent).[1]
Monognathus | |
---|---|
M. jesperseni | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Anguilliformes |
Family: | Monognathidae |
Genus: | Monognathus Bertin, 1936 |
Species | |
15, see text. |
Description
The dorsal and anal fins lack bony supports and the pectoral fins are missing. The snout has a fang connected to glands, which are venomous in adults.[2] These eels are virtually blind, with rudimentary eyes and small olfactory organs, although the male olfactory organs are enlarged, perhaps suggesting a method of "sniffing out" a mate.[1]
Typical lengths are from 4 to 10 cm (1.5–4 in), the maximum length recorded is 15.9 cm (6.3 in).
Distribution
They are found at depths of over 2,000 m (6,600 ft), and are found in all oceans.[3][1]
Species
The fifteen known species are:[3]
- Monognathus ahlstromi Raju, 1974 (Paddletail onejaw)
- Monognathus berteli J. G. Nielsen & Hartel, 1996.
- Monognathus bertini Bertelsen & J. G. Nielsen, 1987.
- Monognathus boehlkei Bertelsen & J. G. Nielsen, 1987.
- Monognathus bruuni Bertin, 1936.
- Monognathus herringi Bertelsen & J. G. Nielsen, 1987.
- Monognathus isaacsi Raju, 1974.
- Monognathus jesperseni Bertin, 1936.
- Monognathus jesse Raju, 1974.
- Monognathus nigeli Bertelsen & J. G. Nielsen, 1987.
- Monognathus ozawai Bertelsen & J. G. Nielsen, 1987.
- Monognathus rajui Bertelsen & J. G. Nielsen, 1987.
- Monognathus rosenblatti Bertelsen & J. G. Nielsen, 1987.
- Monognathus smithi Bertelsen & J. G. Nielsen, 1987.
- Monognathus taningi Bertin, 1936.
References
- BÖHLKE, EUGENIA B.; BÖHLKE, JAMES E.; LEIBY, MARK M.; McCOSKER, JOHN E.; BERTELSEN, E.; ROBINS, CATHERINE H.; ROBINS, C. RICHARD; SMITH, DAVID G.; TIGHE, KENNETH A. (1989). Orders Anguilliformes and Saccopharyngiformes: Part 9, Volume 1. Yale University Press. ISBN 978-1-933789-19-4. JSTOR j.ctvbcd0dm.
- Poulsen, Jan Y.; Miller, Michael J.; Sado, Tetsuya; Hanel, Reinhold; Tsukamoto, Katsumi; Miya, Masaki (2018-07-25). "Resolving deep-sea pelagic saccopharyngiform eel mysteries: Identification of Neocyema and Monognathidae leptocephali and establishment of a new fish family "Neocyematidae" based on larvae, adults and mitogenomic gene orders". PLOS ONE. 13 (7): e0199982. Bibcode:2018PLoSO..1399982P. doi:10.1371/journal.pone.0199982. ISSN 1932-6203. PMC 6059418. PMID 30044814.
- Froese, Rainer, and Daniel Pauly, eds. (2011). "Monognathidae" in FishBase. June 2011 version.