Pipidae is a clade of Anura that diverged relatively early from other frogs in the phylogeny of the group. Pipids have a unique combination of morphological features, some of which appear to represent a mix of adaptations to aquatic life and plesiomorphic characters of Anura. The present study describes the karyotype of Pipa carvalhoi Miranda-Ribeiro, 1937, including morphology, heterochromatin distribution, and location of the NOR site. The diploid number of P. carvalhoi is 2n=20, including three metacentric pairs (1, 4, 8), two submetacentric (2 and 7), three subtelocentric (3, 5, 6), and two telocentric pairs (9 and 10). C-banding detected centromeric blocks of heterochromatin in all chromosome pairs and the NOR detected in chromosome pair 9, as confirmed by FISH using the rDNA 28S probe. The telomeric probes indicated the presence of interstitial telomeric sequences (ITSs), primarily in the centromeric region of the chromosomes, frequently associated with heterochromatin, suggesting that these repeats are a significant component of this region. The findings of the present study provide important insights for the understanding of the mechanisms of chromosomal evolution in the genus Pipa, and the diversification of the Pipidae as a whole.

中文翻译：

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Pipa carvalhoi Miranda-Ribeiro, 1937（Pipidae，Anura）核型中 (TTAGGG)n 重复的染色体分布。


蛙科是无尾蛙的一个分支，在该类群的系统发育中较早地与其他蛙类分化。琵琶鱼具有独特的形态特征组合，其中一些似乎代表了对水生生物的适应和无尾目的拟形特征的混合。本研究描述了 Pipa carvalhoi Miranda-Ribeiro, 1937 的核型，包括形态、异染色质分布和 NOR 位点的位置。 P. carvalhoi的二倍体数为2n=20，其中包括3个定着丝粒对（1,4,8），2个亚定着丝粒对（2和7），3个亚端着丝粒对（3,5,6），2对端着丝粒对（9和10） ）。使用 rDNA 28S 探针通过 FISH 证实，C 显带在所有染色体对中检测到异染色质着丝粒块，并在第 9 号染色体对中检测到 NOR。端粒探针表明间质端粒序列（ITS）的存在，主要位于染色体的着丝粒区域，通常与异染色质相关，表明这些重复是该区域的重要组成部分。本研究的结果为理解琵琶属染色体进化机制以及琵琶科整体的多样化提供了重要的见解。