Molecular phylogeny, biogeography and ecological niche modelling ofCardiocrinum(Liliaceae): insights into the evolutionary history of endemic genera distributed across the Sino-Japanese floristic region

Abstract

Background and Aims The patterns of evolutionary assembly in the Sino-Japanese floristic region (SJFR) remain largely unknown due to a lack of integrative multidimensional studies throughout the region. To address this issue, we elucidated the evolutionary history of Cardiocrinum (Liliaceae), a genus containing four taxa distributed across the SJFR.Methods Fifty-four populations were sampled throughout the geographical range of Cardiocrinum to assess genetic structure, analyse phylogenetic relationships and reconstruct ancestral area based on six chloroplast DNA (cpDNA) fragments and three low copy nuclear genes (LCNG). Ecological niche modelling was used to examine the potential range shifts of Cardiocrinum in response to climatic change.Key Results The molecular data showed high genetic similarity in the cpDNA (98Á37 %) and LCNG (94Á53 %) sequences. The biogeographical analyses revealed that the ancestor of Cardiocrinum diversified during the late Miocene (approx. 7Á32 Mya) in Central China. The ancestor of the C. giganteum lineage dispersed westward to the Himalayas and south-west China with the split between C. giganteum and C. giganteum var. yunnanense occurring around 4Á11 Mya consistent with the period of orogeny of the Hengduan Mountains. Some populations of the C. cathayanum lineage dispersed eastward to south Japan via the land bridge approx. 4Á97 Mya, providing opportunities for allopatric speciation of C. cordatum. The predicted suitable habitats of Cardiocrinum have become smaller and more fragmented since the Last Glacial Maximum.Conclusions Our study provides evidence of a biogeographical pattern of dispersal from Central China to the Himalayas in the west and Japan in the east for genera distributed across the SJFR, and highlights that the orogeny of the Hengduan Mountains and fluctuations of the sea level of the East China Sea played important roles in promoting species divergence.

A pre‐Miocene Irano‐Turanian cradle: Origin and diversification of the species‐rich monocot genus Gagea (Liliaceae)

“…The root of the Gagea phylogeny was calibrated using the crown age of the tribe Tulipeae, 39.9 Ma, provided by Givnish et al (). A similar approach was used in the calibration of the root nodes of a recent Cardiocrinum (Lilieae) phylogeny (Yang et al, ). Independent estimations of the crown and stem ages for the tribe Lilieae by Huang et al () were similar to Givnish et al ().…”

Molecular phylogenetics and historical biogeography of the tribe Lilieae (Liliaceae): bi-directional dispersal between biodiversity hotspots in Eurasia

“…In recent molecular phylogenetic studies, tribe Lilieae contains four closely related genera and the infrageneric relationships have been studied extensively (Gao et al, 2013;Day et al, 2014;Yang et al, 2016): Fritillaria, Lilium (including Nomocharis), Cardiocrinum and Notholirion. Fritillaria is the largest genus of the tribe Lilieae and comprises approx.…”

Geographic and subsequent biotic isolations led to a diversity anomaly ofHeterotropa(Aristolochiaceae) in insular versus continental regions of the Sino-Japanese Floristic Region

“…These results were concordant with the estimation of our previous study using the average substitution rate of the ITS region (9.3 Mya; Takahashi & Setoguchi, 2018). During the late Miocene, regressions and transgressions of the East China Sea (Haq, Hardenbol, & Vail, 1987) caused land-bridge formation that allowed the migration of temperate plants between the mainland China and insular systems (Cao, Comes, Sakaguchi, Chen, & Qiu, 2016; Yang et al, 2017). Furthermore, our study revealed that besides the insular clade, the mainland China clade was also composed of subclades, which corresponded to taxa geographic distribution (Fig.…”

“…In the eastern island systems, sea level changes due to climatic oscillations have caused repeated formation and division of land-bridges in the East China Sea (Ujiie, 1990), and these events have provided opportunities for population expansion and fragmentation (Qiu, Fu, & Comes, 2011). Many phylogeographic studies have revealed that the present interspecific and intraspecific genetic structures of temperate plants in this region reflected the range shifts caused by climatic oscillations (Li, Yan, & Ge, 2012; Sakaguchi et al, 2012; Setoguchi et al, 2006; Wang et al, 2015; Yang et al, 2017). It has been considered that these climatic and associated environmental changes during the Pleistocene triggered range fragmentation, vicariance, and population isolation (Qiu et al, 2011).…”

“…However, many studies conducted in the SJFR have only discussed the role of allopatric fragmentation due to geographic and climatic events, and few studies have considered other factors as drivers of the diversification of the temperate plants. In addition, although the high endemism in the SJFR provides an outstanding opportunity for investigating the evolutionary history of plant diversification (Yang et al, 2017), to date, most phylogeographic studies in the region have focused on individual species or only small groups, including fewer than 10 taxa (But Mitsui et al, 2008; Yoichi, Jin, Peng, Tamaki, & Tomaru, 2017). Thus, our knowledge of the diversification process of temperate plants in the SJFR remains fragmentary, due to a lack of integrative multidimensional studies of morphology, phylogeny, biogeography, and ecology with adequate sampling of diversified groups.…”