''Ceratothoa steindachneri'' is an

ectoparasite Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has ...

known as a tongue biter. It parasitises

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...

by attaching to the tongue, causing

atrophy Atrophy is the partial or complete wasting away of a part of the body. Causes of atrophy include mutations (which can destroy the gene to build up the organ), poor nourishment, poor circulation, loss of hormonal support, loss of nerve supply t ...

. It then replaces the tongue.

Description

''C. steindachneri'' has a oval to rounded body and is generally stocky. It is tan or ivory coloured, with considerable

sexual dimorphism Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...

in this species, with females (15-23 mm) being much larger than males (4.8-5.3 mm). Females are also more rotund, males are more stocky and rectangular.

Distribution

''C. steindachneri'' is found in the northern

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...

and the

Mediterranean Sea The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the ea ...

. It was first found in British waters at

Whitsand Bay Whitsand Bay, situated in south east Cornwall, England, runs from Rame Head in the east to Portwrinkle in the west. It is characterised by sheer, high cliffs, dramatic scenery and long stretches of sandy beaches. The South West Coast Path runs t ...

Cornwall Cornwall (; kw, Kernow ) is a historic county and ceremonial county in South West England. It is recognised as one of the Celtic nations, and is the homeland of the Cornish people. Cornwall is bordered to the north and west by the Atlantic ...

, in 1996 in the

lesser weever The lesser weever (''Echiichthys vipera'') is a venomous weever of the family Trachinidae, in the order Perciformes, and the class Actinopterygii. It is generally found on the sandy sea beds of the open sea, near the shore. Lesser weevers may st ...

fish. It has since be found all around the coast of Britain.

Host species

It is a

generalist species A generalist species is able to thrive in a wide variety of environmental conditions and can make use of a variety of different resources (for example, a heterotroph with a varied diet). A specialist species can thrive only in a narrow range of env ...

that can parasitise a wide range of fish species, including the shortnose greeneye (''Chlorophthalmus agassizi''), lesser weever fish (''

Echiichthys vipera The lesser weever (''Echiichthys vipera'') is a venomous weever of the family Trachinidae, in the order Perciformes, and the class Actinopterygii. It is generally found on the sandy sea beds of the open sea, near the shore. Lesser weevers may st ...

''),

red porgy The red porgy (''Pagrus pagrus''), or common seabream, is a species of marine ray-finned fish in the family Sparidae. It is found in shallow waters on either side of the Atlantic Ocean, being present on the western coast of Europe and the Mediter ...

(''Pagrus pagrus''),

comber Comber ( , , locally ) is a town in County Down, Northern Ireland. It lies south of Newtownards, at the northern end of Strangford Lough. It is situated in the townland of Town Parks, the civil parish of Comber and the historic barony of Cast ...

(''Serranus cabrilla''),

painted comber The painted comber (''Serranus scriba'') is a species of marine ray-finned fish, a sea bass from the subfamily Serraninae, classified as part of the family Serranidae which includes the groupers and anthias. It is found in the eastern Atlantic O ...

(''Serranus scriba''), brown comber (''Serranus hepatus''), annular seabream (''Diplodus annularis''), and common two-banded sea bream (''Diplodus vulgaris''). ''C. steindachneri'' has also been reported on ''

Raja asterias ''Raja'' (; from , IAST ') is a royal title used for South Asian monarchs. The title is equivalent to king or princely ruler in South Asia and Southeast Asia. The title has a long history in South Asia and Southeast Asia, being attested fr ...

'', '' R. polystigma'', and '' R. albas'', but these records are yet to be confirmed, as they are most likely the result of trawl transfers.

References

Cymothoida Animal parasites of fish Ectoparasites Crustaceans described in 1879 Crustaceans of the Atlantic Ocean Parasitic crustaceans {{isopod-stub