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Pterygoplichthyini is a tribe of catfishes (order Siluriformes) of the family Loricariidae. It includes two genera, ''Pterygoplichthys'' and the currently undescribed genus referred to as the ''Hemiancistrus annectens'' group. This group was earlier misspelled as Pterygoplichthini.〔 Pterygoplichthyines are known from nearly the entire range of loricariids except for the Guyanas and coastal streams in southeastern Brazil.〔 Pterygoplichthyini is sister to the tribe Ancistrini, which shares the derived presence of an evertible patch of plates on the cheek.〔 ''Pterygoplichthys'' and the ''H. annectens'' group differ most obviously in the number of dorsal fin rays (7 in the ''H. annectens'' group and 9+ in ''Pterygoplichthys'').〔 The two genera are supported as sisters by only one derived characteristic: a modified stomach that is attached to the abdominal wall by a net of connective tissue.〔 This modified stomach allows these fish to breathe air. The stomach is vascularized. A white net of connective tissue surrounds the organ, leaving a circular area in the middle of the stomach free; this connective tissue firmly holds the stomach to the body wall and is better developed in adults. It may also function as a hydrostatic organ, allowing the fish to remain buoyant midwater. ==References== 〔 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「Pterygoplichthyini」の詳細全文を読む スポンサード リンク
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