Mitogenome and phylogenetic analyses support rapid diversification among species groups of small-eared shrews genus <i>Cryptotis</i> (Mammalia: Eulipotyphla: Soricidae)
Kai He, 南方医科大学基础医学学院生物化学与分子生物学教研室，广东省单细胞技术与应用重点实验室，广东 广州510515，中国, Xing Chen, Yinbin Qiu, Liu Zhu, Wenzhi Wang, Neal Woodman, Jesús E. Maldonado, Xinghua Pan, 云南司法鉴定中心，云南 昆明650223，中国, 特拉维夫大学生命科学学院动物学系，特拉维夫 6997801，以色列, 牡丹江师范大学生命科学与技术学院, 黑龙江 牡丹江 157012，中国, 贵州检测分析研究院, 贵州 贵阳 550002，中国, 美国地质调查局东部生态科学中心，马里兰 劳雷尔， 20708，美国, 史密森研究院国家自然历史博物馆脊椎动物学系哺乳动物部，华盛顿特区20560，美国, 史密森保护生物学研究所保护基因组学中心，华盛顿特区 20008，美国, Wildlife Forensic Science Service, Kunming, Yunnan 650223, China
Abstract
The small-eared shrew genus <i>Cryptotis</i> is the third largest in the family Soricidae and occurs in North, Central, and northern South America. In Mexico and Central and South America, most species inhabit geographically isolated moist, montane habitats at middle and high elevations in a typical sky-island pattern. The 49 recognized species have been partitioned into as many as six species groups based on morphological and molecular phylogenetic studies. The relationships among these species groups are poorly resolved, however, and their evolutionary histories, including migration patterns and locomotor adaptations, remain unclear. Herein, we provide a new phylogeny incorporating complete mitochondrial genomes (mitogenomes) and supermatrix approach. We compared different evolutionary scenarios using approximately unbiased (AU), Kishino-Hasegawa (KH), and Shimodaira-Hasegawa (SH) statistical tests. The phylogenetic hypothesis based on mitogenomes revealed novel relationships supporting a basal position for the <i>Cryptotis parvus</i>-group in the genus, and a close relationship between <i>C. gracilis</i> and one clade of the <i>C. thomasi</i>-group. The former relationship is consistent with the least derived humerus morphology and northern distribution of the species. The latter relationship implies multiple migrations between Central and South America. The lack of fine resolution for the species group relationships may be due partly to the lack of taxon sampling. In contrast, multi-approach analyses suggest that the unresolved relationships may be a result of rapid diversification during the early stages of <i>Cryptotis</i> evolution.