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The toothless blindcat, ''Trogloglanis pattersoni'', is a species of North American freshwater catfish endemic to Texas in the United States. This species inhabits subterranean habitats〔 in five artesian wells penetrating the San Antonio Pool of the Edwards Aquifer in and near San Antonio, Texas.〔 The toothless blindcat has no pigmentation and no externally visible eyes. The eye remnants are extremely reduced in size, with very little or no trace of a retina or lens; the optic tract is present, but always regresses before reaching the brain. In juveniles, the eye is under the skin, but as the fish grows, the eyes are withdrawn even further.〔 The head is as long as it is broad. The adipose fin is long and rounded at the end, and is connected to the caudal fin. The dorsal and pectoral fins have spines. The swim bladder in these fish is reduced. The skull is mostly cartilaginous and not well-ossified, unlike the adults of most larger ictalurids. The lateral line is fragmented and reaches to between the anterior to the posterior end of the adipose fin. This species also has a few paedomorphic traits (indicated by small size, kidney morphology, and weak ossification of the skeleton). This species may reach about TL. Its toothless, sucker-like mouth possibly indicates ''T. pattersoni'' is a detritivore.〔 ==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「Toothless blindcat」の詳細全文を読む スポンサード リンク
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