碩士 / 國立臺灣大學 / 海洋研究所 / 91 / The order Squaliformes (dogfishes) consists of 7 families, 22 genera and 98 species in the world. Most dogfishes live in deep waters below 200 m. Recently, fishing depths have increased yearly and dogfishes have been frequently caught, this poses a necessity for the revision of taxonomy of Squaliformes. Furthermore, the systematics of Squaliformes remains controversial, we reconstruct their molecular phylogeny by using mitochondrial DNA sequences.
Most of the specimens were collected from Tashi Fishing Port harvested by bottom trawlers in deep waters around Taiwan. Furthermore, under the project “Studies on the deep-sea fish biodviersity of Taiwan” sponsored by National Science Council, the Ocean Research Vessel I was used to collect specimens below 1000 m deep. Based on morphological study, 19 species belonging to 9 genera, 5 families were identified. Among them, one species is undescribed (Etmopterus sp.) and four species were new records to Taiwan, they are: Centroscyllium kamoharai, Etmopterus bigelowi, Scymnodon squamulosus and Centrophorus squamosus.
Cluster analyses based on morphological characters showed that (1)Centrophorus together with Squalus are divided into two groups; (2)Deania are grouped together with Scymnodon, and does not support the taxonomy that Deania and Centrophorus are members of Centrophoridae; (3) Centroscyllium are the sister group of Centrophorus which does not support the taxonomy that Centroscyllium and Etmopterus are members of Etmoptridae.
Results of phylogenetic analyses based on mitochondrial 12S rRNA and 16S rRNA gene showed that (1) Squalus is a monophyletic group; (2) Deania and Centrophorus are sister groups of the family Centrophoridae; (3) Oxynotus and sleeper sharks are sister groups; (4) Etmopteridae is a monophyletic group; (5) Squaliolus, Dalatias and Isistius are members of the family Dalatidae, but they are not closely related; (6) Dalatidae does not include Somniosinae, Oxynotinae, Etmopterinae and Dalatiinae as proposed by Nelson(1994).
| Identifer | oai:union.ndltd.org:TW/091NTU00279033 |
| Date | January 2003 |
| Creators | Lee, Po-Feng, 李柏鋒 |
| Contributors | Shao, Kwang-Tsao, Dai, Chang-Feng, 邵廣昭, 戴昌鳳 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 140 |
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