Spatial Patterns and Determinants of Endemic Taxa Richness in the Genus Viburnum (Adoxaceae) in China

Abstract

Understanding the distribution patterns and formation mechanisms of endemic taxa is essential for effective biodiversity conservation. China is an important distribution and endemic center for genus Viburnum in Asia. However, the distribution pattern and formation mechanism of endemic taxa of Viburnum remains unclear in China. In this study, we determined the distribution information of 61 endemic taxa of Viburnum through specimens’ review and field surveys. Species distribution models were used to clarify the distribution patterns of the endemic taxa of Viburnum. The findings shows that the hotspot for overall endemic taxa of Viburnum in China is mainly distributed in temperate and subtropical mountainous areas, and the highest richness in the mountainous regions were around the Yunnan-Guizhou Plateau and the Sichuan Basin. About one-third of the endemic taxa of Viburnum were rare species, whose distribution area was scattered and lacked protection. The distribution pattern of the endemic taxa of genus Viburnum can be well explained within the three hypotheses of environmental energy, water availability and climate seasonality. This study provides additional understanding and explanation of endemic species richness distribution and their formation mechanisms. In addition, it provides conservation measures for endemic taxa of genus Viburnum to guide conservationists and policy makers in China.