Cryptic Species and New Discoveries Reveal Greater Biodiversity of Symphurine Tonguefishes (Pleuronectiformes: Cynoglossidae: Symphurus) in the Seas around Taiwan

• Main Authors: Mao-Ying Lee, 李茂熒
• Other Authors: Hong-Ming Chen
• Format: Others
• Language: en_US
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/54430560490890980828

博士 === 國立臺灣海洋大學 === 水產養殖學系 === 101 === Tonguefishes of the genus Symphurus belongs to the family Cynoglossidae, order Pleuronectiformes. Species of Symphurus are usually distributed in tropical to temperate marine waters around world. Most of them in the Indo-Pacific area are deep-sea fishes,occurring between 200 and 1500 m. But Symphurus is distributed throughout the shallow and deep-sea environments in the Eastern Pacific and Western Atlantic areas. Totally, 79 valid species are recorded and undescribed species continue to be described by taxonomists. In past studies, only three species were recorded from waters around Taiwan: Symphurus orientalis, Symphurus strictus, and Symphurus novemfasciatus. With the progress of fishing technology, scientists started to investigate deep waters around Taiwan, and they have many specimens of Symphurus accumulated in recent years. This study used these specimens for using morphological characters, molecular tools and evidence assistant on their classification were also applied in species identification from partial 16S rRNA and COI sequences. Molecular evidences examined genetic distance between species and revealed that actually some cryptic species exist among these nominal species. The Symphurus inhabiting Taiwanese waters have greater biodiversity than previous. This study using both morphological and molecular evidence confirmed that Symphurus novemfasciatus is a junior synonym of Symphurus orientalis. The long-term taxonomic problem that has persisted in undistinguishing Symphurus microrhynchus and Symphurus strictus is also discussed. Two new species, Symphurus megasomus, Symphurus multimaculatus were described and other nominal species were found in Taiwanese waters. Also provided a diagnostic key of Taiwanese Symphurus. This study recorded 11 species of Symphurus in Taiwanese waters, including two previously described species, Symphurus orientalis and Symphurus strictus, four new records, Symphurus bathyspilus, Symphurus hondoensis, Symphurus microrhynchus, and Symphurus undatus, Description of two new species, Symphurus megasomus, Symphurus multimaculatus, and also recognized three possible new species, Symphurus sp. 1, Symphurus sp. 2, Symphurus sp. 3.