Trionyx

...The gap at the front of the plastron is closed by lifting the hinge-like anterior half of the plastron. The genus Trionyx , which belongs to the subfamily Trionychia, includes about 15 species, such as the Japanese soft-shelled turtle T. sinensis japonica (illustration), found in ponds and lakes in Honshu, Shikoku, and Kyushu, and the American spiny soft-shelled turtle T. spiniferus (carapace length 45 cm). This genus includes large species such as the Nile soft-shelled turtle T. triunguis , which has a carapace length of 90 cm, and the Ganges soft-shelled turtle T. gangeticus , which has a carapace length of 70 cm. The Marble soft-shelled turtle Pelochelys bibroni , which is found in Southeast Asia and New Guinea, also reaches a carapace length of 60 to 100 cm. ...

*Some of the terminology that mentions "Trionyx" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…腹甲前部のすきまは，ちょうつがい状の腹甲前半部をもち上げて閉じる。スッポン亜科のスッポン属Trionyxには，本州，四国，九州の池沼に分布するニホンスッポンT.sinensis japonica（イラスト）や，アメリカ合衆国産トゲスッポンT.spiniferus(甲長45cm)など15種ほどが含まれる。本属にはナイルスッポンT.triunguisの甲長90cm，ガンジススッポンT.gangeticusの70cmなど大型種が含まれ，別属の東南アジア･ニューギニア産のマルスッポンPelochelys bibroniも甲長60～100cmに達する。…

※「Trionyx」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報