Monognathus

Monognathus
M. jesperseni
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Anguilliformes
Suborder:	Anguilloidei
Family:	Monognathidae Trewavas, 1937 [1]
Genus:	Monognathus Bertin, 1936
Species
15, see text.
Synonyms [2]
Phasmatostoma Myers, 1940

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). ^[3]

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. ^[4] 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. ^[3]

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. ^{[5] [3]}

Species

The fifteen known species are: ^[5]

• 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

1. Van Der Laan, Richard; Eschmeyer, William N.; Fricke, Ronald (11 November 2014). "Family-group names of Recent fishes". Zootaxa. 3882 (1): 1–230. doi: 10.11646/zootaxa.3882.1.1 . PMID   25543675.
2. Eschmeyer, William N.; Fricke, Ron & van der Laan, Richard (eds.). "Genera in the family Monognathidae". Catalog of Fishes . California Academy of Sciences . Retrieved 9 November 2024.
3. 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.
4. 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.
5. Froese, Rainer; Pauly, Daniel (eds.). "Family Monognathidae". FishBase . June 2011 version.