Simpson Michael G, Simpson Lee M, André James M
Department of Biology, San Diego State University, San Diego, California 92182, USA San Diego State University San Diego United States of America.
Granite Mountains Desert Research Center, University of California, Riverside, PO Box 101, Kelso, California 92309, USA University of California Kelso United States of America.
PhytoKeys. 2024 Dec 30;250:193-213. doi: 10.3897/phytokeys.250.138635. eCollection 2024.
In the process of studying the species and its varieties, we discovered a unique taxon of the genus that resembles but differs in having a mostly densely white-strigose stem vestiture (sometimes with spreading trichomes) and tuberculate to muricate nutlets with often whitish tubercles that are, in comparison with typical , larger, with a wider base and more pointed apex, and more densely spaced. We believe this form to be different enough to describe as a new species, . This new species occurs in southwestern North America: in California and Arizona of the United States and in northern Baja California, Mexico. It occurs in mid- to relatively high elevation mountain regions of mostly desert transition/escarpment in the Transverse and Peninsular Ranges, in the Sonoran and Mohave Deserts, and with some populations scattered in the southern Sierra Nevada. We believe this new species to be closely related to , , , and possibly , of series . Detailed molecular phylogenetic are needed to better establish their interrelationships.
在对该物种及其变种的研究过程中，我们发现了该属的一个独特分类群，它与[相关物种]相似，但不同之处在于其茎上大多密被白色糙伏毛（有时具开展的毛状体），小坚果具瘤状至瘤刺状，通常具带白色的瘤，与典型的[相关物种]相比，更大，基部更宽，顶端更尖，且间距更密。我们认为这种形态差异足够大，足以描述为一个新物种，即[新物种名称]。这个新物种分布于北美西南部：美国的加利福尼亚州和亚利桑那州以及墨西哥的下加利福尼亚半岛北部。它生长在横断山脉和半岛山脉中大多为沙漠过渡带/悬崖的中高海拔山区，索诺兰沙漠和莫哈韦沙漠，以及一些种群散布在内华达山脉南部。我们认为这个新物种与[相关物种系列中的其他物种]密切相关，可能与[相关物种系列中的其他物种]也有关系。需要详细的分子系统发育研究来更好地确定它们之间的相互关系。
