The Permian (Cisuralian) Irati Formation, from the Brazilian southeastern Paraná Basin bears, at some levels, Chondrichthyes, besides other vertebrates. Outcrops of this unit are frequent at the state of São Paulo eastern belt. Two members of the Irati are recognized at this state, Assistência, the upper, and Taquaral. A sandy facies, mostly at the base of the Taquaral, is noteworthy by the richness of the Chondrichthyes, mainly Holocephali. The Petalodontiformes are the Chondrichthyes most abundant, so far referred to Itapyrodus punctatus. Recent studies of several specimens revealed that some morphotypes must belong to different species of the genus Itapyrodus. Others are akin to this genus, justifying a proposition of an endemic family Itapyrodidae. The presence of this endemic family is an argument, among others, for a proposed isolation of two Brazilan Basins northeast Parnaíba and southeast Paraná, during the time of deposition of the Irati, inasmuch as Itapyrodidae are present in both basins.

中文翻译：

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来自巴西 Irati 组（巴拉那盆地）的 Holocephali：起源、古地理和古环境考虑

Permian (Cisuralian) Irati 地层来自巴西东南部的巴拉那盆地，在某些层面上，除了其他脊椎动物外，还有软骨鱼类。该单元的露头在圣保罗州东部地带频繁出现。该州承认有两名 Irati 成员，Assistência、上层和 Taquaral。沙质相，主要在 Taquaral 的底部，值得注意的是丰富的软骨鱼，主要是 Holocephali。Petalodontiformes 是最丰富的软骨鱼类，迄今为止被称为Itapyrodus punctatus。最近对几个标本的研究表明，某些形态类型必须属于Itapyrodus属的不同物种. 其他的与这个属相似，证明了一个地方性家族 Itapyrodidae 的命题。这个地方性家族的存在是一个论据，其中包括提议在 Irati 沉积期间将两个巴西盆地东北帕纳伊巴和巴拉那东南部隔离，因为两个盆地都存在 Itapyrodidae。