Solanaceae diversity in South America and its distribution in Argentina

Abstract Solanaceae is one of the most diverse families in the Americas, particularly in Argentina where it represents the fourth family in terms of species number. Although checklists for most South American countries have been published, some are outdated and there has been no analysis of Solanaceae diversity at country level. We present an updated summary of Solanaceae diversity in South America, an analysis of its distribution in Argentina, and preliminary conservation assessments for all species endemic to Argentina. Regression analyses were used for evaluating the ratio between taxa/area and endemic/total species, multivariate ordering methods were used to analyze the relationships between Argentine ecoregions, and the IUCN criteria were applied for conservation assessments. Results show that Solanaceae comprises 1611 species in South America. The highest diversity is in Peru, which, together with Ecuador, possesses more diversity than expected for the area; Chile and Brazil have the greatest percentage of endemic species. In Argentina, the Chaco ecoregion hosts the highest number of taxa, but largest number of endemic species is found in the Monte ecoregion. According to the IUCN criteria, 28 endemic species from Argentina are considered threatened. We discuss South American countries and Argentine ecoregions in terms of conservation priorities.摘要 茄科（Solanaceae）是美洲物种多样性最为丰富的植物科之一，在阿根廷尤为突出，按物种数量计为该国第四大植物科。尽管多数南美国家的植物名录已公开发布，但部分名录已过时，且目前尚无针对国家尺度的茄科多样性分析研究。本研究更新了南美茄科多样性的概况，分析了该科在阿根廷的分布格局，并针对阿根廷所有特有物种开展了初步的保护评价。本研究采用回归分析评估分类单元-面积比与特有种-总种比的相关性，借助多元排序方法解析阿根廷各生态区之间的关联，并依据世界自然保护联盟（IUCN）标准开展保护评价。研究结果显示，南美地区的茄科植物共计1611种。物种多样性最高的区域为秘鲁，该国与厄瓜多尔的茄科多样性均超出基于其面积的预期水平；智利和巴西的特有种占比最高。在阿根廷，查科（Chaco）生态区的分类单元数量最多，而蒙特（Monte）生态区的特有物种数量最多。依据IUCN标准，阿根廷境内有28种特有茄科物种被列为受威胁物种。本研究从保护优先级的角度，探讨了南美各国及阿根廷各生态区的保护重点。