Anguilliformity

Anguilliformity is a morphological pattern in fishes, named for and typified by the eels. Anguilliform fish have a long, slender body, and travel by anguilliform motion. The caudal fin is often emphasized, with the other fins reduced, absent, or fused with the caudal fin. ^[1] Anguilliformity has evolved independently in many groups, including among others:

Anguilliformes, the eels
Synbranchiformes, the swamp eels
Clariidae, the airbreathing catfishes
Dipnoi, the lungfishes
Cobitidae, the loaches
Gymnotidae, the knifefishes, including the electric eel Electrophorus electricus

^ Adriaens, Dominique; Devaere, Stijn; Teugels, GUY G.; Dekegel, Barbara; Verraes, Walter (2008-10-13). "Intraspecific variation in limblessness in vertebrates: a unique example of microevolution". Biological Journal of the Linnean Society. 75 (3): 367–377. doi:10.1046/j.1095-8312.2002.00029.x. ISSN 0024-4066. Retrieved 2022-10-13.

[Biological_Journal_of_the_Linnean_Society_2008_pp._367–377-1] Adriaens, Dominique; Devaere, Stijn; Teugels, GUY G.; Dekegel, Barbara; Verraes, Walter (2008-10-13). "Intraspecific variation in limblessness in vertebrates: a unique example of microevolution". Biological Journal of the Linnean Society. 75 (3): 367–377. doi:10.1046/j.1095-8312.2002.00029.x. ISSN 0024-4066. Retrieved 2022-10-13.

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