Taxonomic note: There was a long time discussion about the identity of Stylocheilus longicauda (Quoy & Gaimard, 1825) and Stylocheilus striatus (Quoy & Gaimard, 1832). Unfortunately these authors noted that S. striatus was probably the same as S. longicauda, beginning a confusion which has persisted until the present. Today most researchers consider that there are two species of Stylocheilus: S.striatus, with dark longitudinal lines, a mottled colour pattern and compound papillae, and S.longicauda with a uniform yellow or green colour, simple papillae, without lines and an extremely long slender ‘tail’. Despite these species were clearly differentiated, Yonow (2012) reverted back to the confusion by ignoring evidence presented by Rudman (1999) that they are distinct species..
Aplysia striata Quoy & Gaimard, 1832 (original)
Notarchus polyomma Mörch, 1863
Stylocheilus lineolatus Gould, 1852
Description Stylocheilus striatus is a medium sized opisthobranch, reaching up to 65mm, it has a translucent body with patches of greens, browns and white, and often with many branched papillae. This species is distinguished by fine longitudinal brown-to-black lines usually interrupted by ‘eyespots’ with bright blue centres; it has a long tail and a swelling is present in the middle of body, where the parapodial lobes enclose a large gill and an anal siphon. The rhinophores and oral tentacles are long and slender. It may have few or numerous villi, depending on the population. Releases a purple dye when disturbed.
Biology It can be locally common in algal beds and shallow water, especially during the breeding season, but this does not happen every year.
Stylocheilus. From Latin “stylus”, column, pillar + from Greek χεῖλος, “cheilos”, lip, edge.
Striatus. From Latin “striatus”, striated, grooved.
Distribution Circumglobal. Subtropical. There are reports from Australia, Galápagos, Brasil, Caribbean, Philippines, Florida, Hawaii, Cape Verde, Gulf of Mexico, SW India, Maldives, Zanzibar, Mauritius, La Réunion, Mayotte, and Madagascar.
Known georeferenced records of the species: Stylocheilus striatus
Caballer, M., J. Ortea, N. Rivero, G. Carias-Tucker, M. A. E. Malaquías, and S. Narciso. 2015. The opisthobranch gastropods (Mollusca: Heterobranchia) from Venezuela: an annotated and illustrated inventory of species. Zootaxa 4034 (2): 201–256.
Camacho-Garcia, Y., T. Gosliner, and A. Valdes. 2005. Guía de Campo de las babosas marinas del Pacífico Este tropical. California Academy of Sciences, S.l.
Cervera, J. L., G. Calado, C. Gavaia, M. A. E. Malaquías, J. Templado, M. Ballesteros, J. C. García-Gómez, and C. Megina. 2004. An annotated and updated checklist of the opisthobranchs (Mollusca: Gastropoda) from Spain and Portugal (including islands and archipelagos). Boletín Instituto Español de Oceanografía, 20 (1-4): 1-111. L.
Flanders Marine Institute. 2018. Maritime Boundaries Geodatabase: Territorial Seas. Maritime Boundaries Geodatabase. (http://www.marineregions.org/).
Long, S. J.2006. Bibliography of Opisthobranchia 1554-2000. Bayside Books & Press, Tustin, CA, U.S.A. 672p.
Malaquias, M. A., and G. J. P. Calado. 1997. The malacological fauna of Salvage Islands - 1. Opisthobranch Molluscs. Bol. Mus. Mun. Funchal, 49(281): 149-170.
Malaquias, M., G. Calado, V. Padula, G. Villani, and J. L. Cervera. 2009. Molluscan diversity in the North Atlantic Ocean: new records of opisthobranch gastropods from the Archipelago of the Azores. Marine Biodiversity. 2: e38.
Ortea, J., L. Moro, J. J. Bacallado, and J. J. Sanchez. 2008. Nuevas aportaciones a la fauna de opistobranquios (Mollusca: Gasteropoda) de las islas Canarias. Vieraea 36: 129-136. 36: 129–136.
Ortea, J., J. Espinosa, M. Caballer, and Y. Buske. 2012. Initial inventory of the seaslugs (Opisthobranchia and Sacoglossa) from the expedition Karubentos, held in May 2012 in Guadeloupe (Lesser Antilles, Caribbean Sea). Revista de la Academia Canaria de Ciencias 24: 153-182.
Quoy, J. R. C., and J. P. Gaimard. 1832. Voyage de découvertes de l’ “Astrolabe” exécuté par ordre du Roi, pendant les années 1826-1829, sous le commandement de M. J. Dumont d’Urville. Zoologie, Tome 2. J. Tatsu.
Valdés, A., J. Hamann, D. W. Behrens, and A. DuPont. 2006. Caribbean sea slugs: a field guide to the opisthobranch mollusks from the tropical northwestern Atlantic. Washington: Sea Challengers Natural History Books. 289 pp.
Wirtz, P., and H. Debelius. 2003. Mediterranean and Atlantic invertebrate guide. ConchBooks, Hackenheim, Germany.