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''Platyrhina'' is a genus of rays in the family Platyrhinidae, containing three species. They are native to the warm-temperate to tropical marine waters in the western Pacific Ocean. They are little-known bottom-dwellers that feed on small invertebrates such as crustaceans, molluscs, and worms. The fanray is found inshore to a depth of 60 m on rocky or rock sandy bottoms. ''Platyrhina'' species have rounded heart-shaped pectoral fin discs with short, blunt snouts. Their tails are long and shark-like, slightly flattened with lateral ridges. The two dorsal fins and the caudal fin are large and rounded; the caudal fin lacks a lower lobe.〔 The teeth are small and arranged in pavement-like rows for crushing shelled prey.〔(中国团扇鳐 ). ''百度百科''. Retrieved November 28, 2008.〕 Their bodies are covered with minute dermal denticles; there are also several rows of denticles inside the buccopharyngeal cavity. The shape of these denticles in ''Platyrhina'' and the similar ''Platyrhinoidis'' distinguish them from all other guitarfish species. There are large thorns around the eyes and on the shoulders, and arranged in rows along the back and tail. Unlike ''Platyrhinoidis'', ''Platyrhina'' species have an additional lateral row of thorns on both sides of the tail, and no rostral thorns. As far as known, they are ovoviviparous, with the developing fetuses primarily sustained by large yolk sacs.〔 Research on fanrays in Ariake Bay, Japan, indicates that they are faster-growing, earlier-maturing, and shorter-lived than many other ray species. Male fanrays mature at 2.1 years and females at 2.9 years; the females grow larger and more slowly than males. The maximum known age is 5 years for males and 12 years for females. These rays are typically inoffensive but care should be exercised regarding their large, sharp thorns.〔 ==Species== * ''Platyrhina hyugaensis'' Iwatsuki, Miyamoto & Nakaya, 2011 (Hyuga fanray) * ''Platyrhina sinensis'' Bloch & J. G. Schneider, 1801 (Fanray) * ''Platyrhina tangi'' Iwatsuki, J. Zhang & Nakaya, 2011 (Yellow-spotted fanray) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Platyrhina」の詳細全文を読む スポンサード リンク
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