Somniosus (Rhinoscymnus) cheni sp. nov., A New Species of Sleeper Shark (Squaliformes: Somniosidae) from Eastern Taiwan, with Aspects of Embryo Biology
Hua-Hsun Hsu
Marine Studies Section, Center for Environment and Water, Research Institute, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia.
Chia-Yen Lin
Department of Environmental Biology and Fisheries Science, National Taiwan Ocean University, Keelung 20224, Taiwan
George Chen Shark Research Center, National Taiwan Ocean University, Keelung 20224, Taiwan.
Shoou-Jeng Joung
Department of Environmental Biology and Fisheries Science, National Taiwan Ocean University, Keelung 20224, Taiwan
George Chen Shark Research Center, National Taiwan Ocean University, Keelung 20224, Taiwan.
Communicated by Hin-Kiu Mok
A new species of sleeper shark is described based on a 134.0 cm total length pregnant female collected from off Hualien, eastern Taiwan. The species belongs to a small species group (subgenus Rhinoscymnus) and can be distinguished from its congeners in having a smaller second dorsal fin, smaller eyes, more rows of teeth in the upper jaw and fewer in the lower jaw, and a different body proportion. Moreover, the specimen had 33 embryos, which is substantially more than the two other small species in the subgenus.Information on embryo biology are also provided.
Keywords
Elasmobranch, Litter size, Morphology, Sex-bias, Taxonomy.
