Ameroglossum is composed of shrubs endemic to inselbergs in north-eastern Brazil, currently circumscribed in Linderniaceae. Chromosomal counts for this family are few, but quite variable, ranging from 2n = 14 to 60. We investigated the chromosomal numbers of 14 species of Linderniaceae with emphasis on Ameroglossum and analysed the distribution of heterochromatin and 5S and 35S rDNA sites for most species. We found 2n = 60 for the species of Ameroglossum (except Ameroglossum genaroanum with 2n = 64), Catimbaua and Isabelcristinia, 2n = 50 for Cubitanthus alatus and 2n = 28 for Torenia thouarsii and Vandellia diffusa. All of them had small, similar chromosomes and 5S and 35S rDNA sites overlapping with CMA+ bands. The species with 2n = 50–64 showed a single pair of 5S and 35S rDNA sites, V. diffusa had two pairs of 5S and one pair of 35S rDNA sites and T. thouarsii had two pairs of each. Furthermore, other CMA+ and DAPI+ bands have been seen in almost all species. The karyotypical similarities among the species of Ameroglossum, Catimbaua, Cubitanthus and Isabelcristinia suggest a close relationship between representatives of Linderniaceae typical of inselbergs.

中文翻译：

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Ameroglossum (Linderniaceae) 的核型分化和巴西inselbergs 特有的密切相关属

Ameroglossum 由巴西东北部岛内特有的灌木组成，目前属于林德尼亚科。该科的染色体计数很少，但变化很大，范围从 2n = 14 到 60。我们研究了 14 种林德尼科植物的染色体数目，重点是 Ameroglossum，并分析了大多数物种的异染色质和 5S 和 35S rDNA 位点的分布。我们发现 Ameroglossum 的物种（除了 Ameroglossum genaroanum，2n = 64）、Catimbaua 和 Isabelcristinia 的物种为 2n = 60，Cubitanthus alatus 的物种为 2n = 50，而 Torenia thouarsii 和 Vandellia diffusa 的物种为 2n = 28。它们都有小的、相似的染色体以及与 CMA+ 条带重叠的 5S 和 35S rDNA 位点。具有 2n = 50-64 的物种显示出一对 5S 和 35S rDNA 位点，V。diffusa 有两对 5S 和一对 35S rDNA 位点，T. thouarsii 有两对。此外，几乎所有物种中都发现了其他 CMA+ 和 DAPI+ 条带。Ameroglossum、Catimbaua、Cubitanthus 和 Isabelcristinia 物种之间的核型相似性表明，典型的 inselbergs 的林德尼亚科代表之间存在密切关系。