Gnathiidae Explained

The Gnathiidae are a family of isopod crustaceans. They occur in a wide range of depths, from the littoral zone to the deep sea. The adults are associated with sponges and may not feed.^[1] The juvenile form is known as a 'praniza', and it is a temporary parasite of marine fish.^[1] These forms are not larvae; Gnathiidae instead become parasitic during the manca stage. Mancae of the Gnathiidae closely resemble the adult form, however they lack the final pair of pereiopods.

Taxonomy in the family relies on male characters, such that females and juveniles cannot be reliably identified.^[1] The family contains 182 species,^[2] divided among the following genera:^[3]

• Afrignathia Hadfield & Smit, 2008
• Bathygnathia Dollfus, 1901
• Bythognathia Camp, 1988
• Caecognathia Dollfus, 1901
• Elaphognathia Monod, 1926
• Euneognathia Stebbing, 1893
• Gibbagnathia Cohen & Poore, 1994
• Gnathia Leach, 1814
• Monodgnathia Cohen & Poore, 1994
• Paragnathia Omer-Cooper & Omer-Cooper, 1916
• Tenerognathia Tanaka, 2005
• Thaumastognathia Monod, 1926

The extinct Jurassic genus Urda is thought to represent a stem-group to the family, and is suggested to have had a similar parasitic lifestyle.^{[4] [5]}

External links

• Gnathiidae Australian Isopoda

Notes and References

1. Web site: Suborder Gnathiidae [''sic''] |author= Richard Brusca, Vania R. Coelho & Stefano Taiti |work=Guide to the Coastal Marine Isopods of California |access-date=August 28, 2010 |publisher=[[Tree of Life Web Project]] |year=2001].
2. Jörundar Svavarsson . 2006 . New species of Gnathiidae (Crustacea, Isopoda, Cymothoida) from seamounts off northern New Zealand . . 1173 . 39–56 .
3. Web site: WoRMS . 2010 . Gnathiidae . M. Schotte . C. B. Boyko . N. L. Bruce . G. C. B. Poore . S. Taiti . G. D. F. Wilson . World Marine, Freshwater and Terrestrial Isopod Crustaceans database . . August 28, 2010.
4. Nagler . Christina . Hyžný . Matúš . Haug . Joachim T. . 2017-03-09 . 168 million years old "marine lice" and the evolution of parasitism within isopods . BMC Evolutionary Biology . 17 . 1 . 76 . 10.1186/s12862-017-0915-1 . 1471-2148 . 5345136 . 28279151 . free .
5. Schädel . Mario . Nagler . Christina . Hyžný . Matúš . 2023 . Fossil relatives of extant parasitic crustaceans from the Mesozoic of Europe - Parientes fósiles de parásitos actuales de crustáceos, del Mesozoico de Europa . Boletín de la Sociedad Geológica Mexicana . 75 . 2 . 1–57 . 10.18268/BSGM2023v75n2a220323 . 27221848 . 1405-3322. free .