Abstract
Freshwater eels (Anguilla spp.) have been shrouded in mystery in areas where they were present ever since the beginning of human thought because of their unusual bodies compared with other fishes and their mysterious life histories, which surprised Aristotle, one of the great thinkers of ancient Greece. With their slender, snake-like bodies, and barely noticeable scales and gills, it is easy to forget that they are fish. There are relatively few species and only two different sets of body coloration and fin positions, so the body forms of all anguillid eels are generally quite similar, with all northern temperate species of Anguilla essentially looking the same in their external appearance. The taxonomy and morphology of freshwater eels has attracted the attention of some ichthyologists though, going back to Kaup (1856), Günther (1870), and Ege (1939), and these previous works were more recently reexamined by Watanabe (2003). The genus was classified into 19 species and subspecies after several studies. Recently, genetic identification has been increasingly used to identify anguillid eels; however, as discussed in this chapter, morphology is still a valuable tool for distinguishing among anguillid eel species worldwide.
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Watanabe, S. (2023). Morphology and Taxonomy. In: Tsukamoto, K., Kuroki, M., Watanabe, S. (eds) Eel Science. Fisheries Science Series. Springer, Singapore. https://doi.org/10.1007/978-981-99-5692-0_1
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