The tree frog Aplastodiscus is a Neotropical taxon that encompasses 15 species in the Atlantic forest biome, with one isolated species in the Central Brazilian Cerrado. To date, only 8 species have been karyotyped, showing high levels of diploid number variation, which allowed clustering species in chromosome number groups: 2n = 24 (Aplastodiscus perviridis group), 2n = 22 (Aplastodiscus albofrenatus group), 2n = 20, and 2n = 18 (both within Aplastodiscus albosignatus group). This study aims to report karyotypic information on 4 species from the last 2 groups using classical and molecular cytogenetic techniques and hypothesize chromosomal evolutionary trends within the species groups. Aplastodiscus weygoldti showed 2n = 22; Ag-NOR and FISH 18S rDNA signals were located in the interstitial region of the short arms of chromosome pair 6. Aplastodiscus cavicola, Aplastodiscus sp. 4, and Aplastodiscus sp. 6 showed 2n = 18; Ag-NOR and FISH 18S rDNA bands were located in the terminal region of the long arm of chromosome pair 9. Our results support multiple and independent chromosome fusion events within Aplastodiscus, including a new chromosome fission event. Ag-NOR and FISH 18S rDNA patterns were restricted to the small chromosome pairs, similar to the other species within this genus, and confirm overall chromosome morphology conservation among the genera of Cophomantinae.
Cytogenet Genome Res

中文翻译：

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绿色物种Aplastodiscus Lutz的四种物种的细胞遗传学，1950年（阿努拉（Anura）：Cophomantinae）：对属的染色体进化的新见解

树蛙Aplastodiscus是一种新热带类群，在大西洋森林生物群系中包含15种，在巴西中部Cerrado中包含一种孤立的物种。迄今为止，只有8个物种进行了核型鉴定，显示出高水平的二倍体数量变异，从而允许在染色体数量组中进行聚类：2n = 24（perplastodiscus perviridis组），2n = 22（Aplastodiscus albofrenatus组），2n = 20和2n = 18（均在白色拟青霉组内）。这项研究的目的是使用经典和分子细胞遗传学技术报告最近2个组中4个物种的核型信息，并假设物种组内的染色体进化趋势。魏氏乳杆菌显示2n = 22; Ag-NOR和FISH 18S rDNA信号位于6号染色体对短臂的间质区域。Aplastodiscus cavicola，Aplastodiscus sp。4，和Aplastodiscus sp。6表示2n = 18; Ag-NOR和FISH 18S rDNA条带位于9号染色体对长臂的末端区域。我们的研究结果支持了非原生质体内部多次独立的染色体融合事件，包括新的染色体分裂事件。Ag-NOR和FISH 18S rDNA模式被限制在小染色体对上，与该属中的其他物种相似，并证实了Cophomantinae属中总体染色体形态上的保守。
细胞遗传基因组研究