Ophelia bicornis Savigny in Lamarck, 1818

Faulwetter, Sarah, Simboura, Nomiki, Katsiaras, Nikolaos, Chatzigeorgiou, Giorgos & Arvanitidis, Christos, 2017, Polychaetes of Greece: an updated and annotated checklist, Biodiversity Data Journal 5, pp. 20997-20997 : 20997

Ophelia bicornis Savigny in Lamarck, 1818

Ophelia bicornis Savigny in Lamarck, 1818 | Ophelia radiata (Delle Chiaje, 1828)

Notes

Species complex with a confused taxonomic history. Originally described from the Gulf of Naples. Fauvel (1927) considered Ophelia bicornis and Ophelia radiata as distinct based on the number of gill pairs ( Ophelia radiata : 14 pairs; Ophelia bicornis : 15 pairs) and geographic distribution. However, both species and intermediate forms (with 14 gill pairs on one side and 15 on the other) have been found to co-occur by Britton-Davidian and Amoureux (1982), who also found genetic differences between the two forms in an Atlantic population, with asymmetric specimens belonging to either of the two genetic variants. Based on these findings, the authors consider the species distinct. However, they were not able to assign Mediterranean specimens to either of the two Atlantic forms. Maltagliati et al. (2005) consider the results inconclusive and refer to the complex as Ophelia bicornis sensu lato. Parapar (2012) studied individuals of both Ophelia radiata and Ophelia bicornis from the collections of the Natural History Museums in Copenhagen and Madrid and could not find any differences apart from the number of gill pairs - a character which he considered too unreliable for discrimination.