Taxonomic studies on the sea slugs of the family Phyllidiidae（Mollusca: Heterobranchia: Nudibranchia）from the Northern Taiwan
Szu-Ju Lai *1, Yen-Wei Chang 2, Chien-Hui Yang 1
1. Institute of Marine Biology, Nation Taiwan Ocean University, Taiwan
2. Department of Marine Recreation, National Penghu University of Science and Technology, Taiwan
Sea slugs are categorized to the Heterobranchial subclass within the Gastropoda class. The distinct characters are the size reduction, degeneration, inward shrinkage, or complete disappearance of the shells. With the technological improvements of underwater photography and the promotion of social media, colorful sea slugs have also been attracted the attention. However, there are many incorrect identifications for the sea slugs from the illustrated handbook or the websites. The species of Phyllidiidae Rafinesque (1814) are commonly found from the coral reefs in the Indo-West Pacific. The distinguishable characters of this family are without the dorsal secondary gills, jaws and radula of the mouth. Although some species are dominant in Taiwan and with the bigger body size, they are often misidentified due to the similar colorations. Since there is no any research to examine the taxonomy of Phyllidiidae sea slugs carefully in Taiwan, this study starts to record those species from the northern Taiwan. Besides the detail descriptions of the morphological characters, the sequences of the barcode gene (MtCOI gene) will be used to confirm the species. Until now, there are 4 genera and 17 species of the Phyllidiidae have been collected in this study. Next the barcode gene dataset will be analyzed by the species delimitation model of Automatic Barcode Gap Discovery (ABGD) to define the intraspecific and interspecific divergences for the Phyllidiidae sea slugs. The present study expects to identify the different species of the Phyllidiidae evidently via the combination of morphological characteristics and molecular barcoding sequences.
Keywords: Nudibranch, Sea slug, Phyllidiidae, Taxonomy, Barcoding gene
