Phylogeny And Taxonomy Of The’Hairy-Fig’ Complex Of Ficus Sect. Eriosycea (Moraceae) In China

Fig trees (Ficus, Moraceae), occurring in tropical and subtropical forests all over the world, possess life forms such as terrestrial trees, shrubs, hemi-epiphytic, climbers and creepers. They are monoecious or dioecious and play a significant role in forest succession. Figs can be distinguished by the unique closed inflorescences (syconia), which constitute obligate pollination mutualism with fig-wasps. Subgenus Ficus, one of the six subgenera, includes sections Ficus and Eriosycea. Section Eriosycea comprises about 34 species, ranging from Sino-Himalayan region to New Guinea with a concentrated distribution in the western part of Malaysia. Seven species of this section recorded in China. Hairy-fig complex of sect. Eriosycea includes F. hirta, F. esquiroliana, F. simplicissima and a population entity misidentified as F.fulva Reinw. ex Bl. in China. These species are difficult to be delimitated after original references tracing, specimen consulting, field survey and morphological anatomy. Among them, F. esquiroliana can be roughly distinguished by the characters such as arbor life form, larger lamina, longer indumentum, abaxially white soft felted hairs and larger syconia. In order to further evaluate the species status,83 samples of the complex were selected for molecular analysis. ITS, ETS and trnH-psbA were applied for constructing phylogenetic trees and 16 fluorescently labeled microsatellite primers were selected for cluster analysis by the soft STRUCTURE and NTSYS. The results showed that:1. All the species of hairy-fig complex make up one well supported clade (PP=1, MPBS=100, MLBS>99) on the phylogenetic trees, which indicated that it is reasonable to combine the hairy-fig complex recorded in China into the one species.2. Using STRUCTURE, the estimated posterior probability plateaued at K= 3. The populations of F. hirta and F. simplicissima contained three genetic clusters, infered that there is no differnce between the two species. Although the population of F. fulva sensu Zhou & Gilbert was assigned to a genetic cluster, its restricted distribution range in southeast Yunnan (sympatric with part of the samples of F. hirta) suggested that its genetic background is consistent with that of F. hirta. The population of F. esquiroliana collected from different provinces assigned to one particular genetic cluster, indicated its special genetic background.3. Hairy-fig complex showed high genetic similarity coefficients (SM>0.82) and F. esquiroliana compose one sub-clade with higher genetic similarity coefficients (SM>0.88) on the phenogram by the soft NTSYS.In conclusion, all the species of the hairy-fig complex recorded in China should be combined as one species F. simplicissima (s. l.), with two varieties:var. simplicissima and var. roxburghii. One new combination and 2 new synonyms are recorded.