Fumana is a diverse genus of the Cistaceae family, consisting of 21 currently accepted species. In this study, nuclear (ITS) and plastid (matK, trnT‐L) molecular markers were used to reconstruct the phylogeny and to estimate divergence times, including 19 species of Fumana. Phylogenetic analyses (Bayesian Inference, Maximum Parsimony and Maximum Likelihood) confirmed the monophyly of Fumana and did not support the infrageneric divisions previously established. The results support four main clades that group species that differ in vegetative and reproductive characters. Given the impossibility to define morphological characters common to all species within the clades, our proposal is to reject infrageneric divisions. Molecular dating and ancestral area analyses provide evidence for a Miocene diversification of the genus in the north‐western Mediterranean. Ancestral state reconstructions revealed ancestral character states for some traits related to xeric and arid habitats, suggesting a preadaptation to the Mediterranean climate.
Aquilegia ecalcarata Maxim. is the only spurless species within the genus Aquilegia and comprises a monophyletic clade with A. yabeana Kitag., A. kansuensis Brühl, and A. rockii Munz. Our previous study on the genetic diversity of those four species revealed that the populations of A. ecalcarata can be divided into two groups, indicating possible genetic difference within A. ecalcarata. However, it is not clear whether the genetic difference is related to the morphological variation among species and groups of A. ecalcarata populations. To answer that question, the morphological variation patterns based on 22 floral and 19 vegetative traits from 42 populations, covering the entire distribution of A. ecalcarata and its relatives, were analyzed in the present study. The result showed that: (i) the differences among the four species were reflected in the floral rather than the vegetative traits; (ii) populations of A. yabeana and A. rockii fell into one cluster each, and each of the six clusters occupied its own distribution range; (iii) one of two A. ecalcarata clusters fell into a subgroup and shared common floral traits with A. rockii; (iv) the individuals of A. ecalcarata form. ecalcarata and form. semicalcarata were often mixed in the same population; and (v) the populations of A. kansuensis were split into two clusters, which differed obviously in floral traits. These results will provide an important morphological basis for the redefinition of species and lay a foundation for the further exploration of the “spurless” A. ecalcarata.
The species delimitation within Abies delavayi complex, consisting of A. delavayi Franch., A. fabri (Mast.) Craib, A. nukiangensis W. C. Cheng & L. K. Fu, and A. delavayi subsp. fansipanensis (Q. P. Xiang, L. K. Fu & Nan Li) Rushforth, has been a subject of long‐term dispute. We combined different lines of evidence, including morphological characters, population‐based mitochondrial DNA and chloroplast DNA sequences, and plastome data to assess its species delimitation. These four independent datasets revealed a consistent result that the four taxa of A. delavayi complex were hardly separated and could be regarded as one species. Our results further suggested that these four taxa might have experienced rapid morphological diversification, following a common expansion triggered by climate oscillations during the Pleistocene. In addition, we surveyed the phylogeographical history of A. delavayi complex as a whole based on ecological niche models and molecular data. These results consistently revealed that this high‐mountain fir complex had experienced glacial expansion and interglacial contraction. Therefore, we propose that A. delavayi complex probably has undergone the phalanx expansion model in response to climate change during the Quaternary. Such expansion patterns demand consideration when establishing conservation strategies for threatened fir species.
The well‐known vicariance and dispersal models dominate in understanding the allopatric pattern for related species and presume the simultaneous occurrence of speciation and biogeographic events. However, the formation of allopatry could postdate the species divergence. We examined this hypothesis using DNA sequence data from three chloroplast fragments and five nuclear loci of Dipelta floribunda Maxim. and D. yunnanensis Franch, two shrub species with the circum Sichuan Basin distribution, combining the climatic niche modeling approach. The best‐fit model supported by the approximate Bayesian computation analysis indicated that D. floribunda and D. yunnanensis diverged during the mid‐Pleistocene period, consistent with the largest glacial period in the Qinghai–Tibet Plateau. The historically interspecific gene flow was identified, but seemed to have ceased after the last interglacial period, when the range of D. floribunda moved northward from the south of the Sichuan Basin. Furthermore, populations of D. floribunda had expanded obviously in the north of the Sichuan Basin after the last glacial maximum (LGM). Relatively, the range of D. yunnanensis expanded before the LGM, and reduced during the post‐LGM especially in the north of the Sichuan Basin, reflecting the asynchronous responses of related species to contemporary climate changes. Our results suggested that complex topography should be considered in understanding distributional patterns, even for closely related species and their demographic responses.
Ficus (Moraceae) is one of the most diverse genera of tree species in the world. The subgenus Spherosuke, section Americanae, comprises several species complexes because its diagnostic structures are extremely variable. Currently, neither there is a phylogenetic hypothesis that can help solve the delimitation problems within these complexes nor has an integrative taxonomic approach been developed. In the present study, morphometric methods were applied to solve the taxonomic problems in the Ficus aurea complex. Morphometric variation of syconia and leaves was analyzed to find differences between four previously recognized forms (fo. aurea, fo. cookii, fo. isophlebia, and fo. tuerckheimii). Syconium characters were analyzed using traditional morphometrics, while leaf shape was evaluated with geometric morphometrics, encompassing 20 populations along two‐thirds of the distribution range of the complex. Data sets from syconia and leaves were tested for possible associations with geographic and rainfall variables. There are significant differences between the four forms in syconium characters and leaf shape. Geography and rainfall variables show significant covariation related to the morphometric variation of syconia but not to leaf shape. Consequently, we propose that the four forms should be repositioned into the specific rank. Besides, F. tecolutensis is also recognized as a separated species from form aurea considering Principal Component Analysis, field observations, and herbarium specimens. An identification key, descriptions, as well as taxonomic comments of the species are provided.
Orographic and climatic oscillations have played crucial roles in shaping the nucleotide diversity and evolutionary history of many species across the Northern Hemisphere. In this study, based on 10 nuclear loci and a chloroplast DNA marker, we analyzed the nucleotide polymorphisms and demographic history of the endangered conifer species Pinus bungeana in Northwest China and investigated the phylogenetic relationships between P. bungeana and two related species, that is, Pinus gerardiana and Pinus squamata. We found that P. bungeana exhibited an extremely low level of nucleotide diversity (πsil = 0.00159). Demographic simulations based on DIYABC analysis showed that P. bungeana underwent demographic expansion and contraction during the Miocene. According to ecological niche modeling, we found that this species survived in situ during the glacial period and was not restricted to southern refugia. We speculate that P. bungeana may have experienced widespread population shrinkage from the Last Interglacial to the Last Glacial Maximum due to geological or climatic events. Isolation‐with‐migration analysis revealed that the divergence (~2.4–4.2 Ma) among P. bungeana and its related species was significantly associated with the Qinghai–Tibetan Plateau uplift events in the mid‐to‐late Tertiary period. Species tree analyses suggested that these three related Pinus species formed a monophyletic clade with high bootstrap support. These results suggest that the Miocene–Pliocene and Pleistocene geological and climatic fluctuations might have profoundly affected the nucleotide diversity and demography of this psychrotolerant conifer species in western China.
Blastenia is a widely distributed lichen genus in Teloschistaceae. We reconstructed its phylogeny in order to test species delimitation and to find evolutionary drivers forming recent Blastenia diversity. The origin of Blastenia is dated to the early Tertiary period, but later diversification events are distinctly younger. We recognized 24 species (plus 2 subspecies) within 6 infrageneric groups. Each species strongly prefers a single type of substrate (17 species occur on organic substrates, 7 on siliceous rock), and most infrageneric groups also show a clear substrate preference. All infrageneric groups tend to have the Mediterranean and Macaronesian distribution, but some epiphytic species have much larger geographic ranges and some evolved after a long‐distance dispersal outside the region. Chlorinated and nonchlorinated anthraquinone chemosyndromes co‐occur in apothecia of most species, but the chemotype has been secondarily reduced in some lineages. One infrageneric group has a marked reduction in apothecial size, associated with a substrate shift to twigs. Only seven species have vegetative diaspores; they also produce apothecia but have smaller ascospores. Genome sizes (22‐35 Mb in Blastenia) are significantly higher in epilithic species. Within‐species genetic variation is low in widely distributed species but high in some epilithic species with small geographical ranges. New taxa are: B. afroalpina, B. anatolica, B. caucasica, B. gennargentuae, B. herbidella subsp. acidophila, B. lauri, B. monticola, B. palmae, B. psychrophila, B. purpurea, B. relicta, B. remota, B. xerothermica, and B. xerothermica subsp. macaronesica. New combinations are: B. festivella and B. subathallina; both names and B. catalinae are lectotypified.
Although plant species with either animal or wind pollination modes are widespread and usually sympatric in nature, the degree of pollen interference from wind‐pollinated species on animal‐pollinated species remains little known. Conifer trees generally release a huge number of pollen grains into the air, floating into our noses and sometimes causing an allergic response. Here we document airborne pollen from two conifers (Pinus densata Mast. and Picea likiangensis (Franch.) E. Pritz.) deposited on the stigmas of eight coflowering insect‐pollinated angiosperms over 2 years in a mountainous forest community, in Shangri‐La, southwest China. Pollen density in the air as well as conifer pollen deposited onto stigmas at short and long distances from the airborne pollen source were quantified. Our results showed that conifer pollen as a proportion of total stigmatic pollen loads in the insect‐pollinated plants varied from 0.16% to 8.67% (3.16% ± 0.41%, n = 735) in 2016 and 0.66% to 5.38% (2.87% ± 0.86%, n = 180), and pollen quantity per unit area was closely related to that of airborne pollen in the air. Conifer pollen deposition on stigmas of insect‐pollinated species decreased greatly with increased distance from the pollen source. In the 10 plant species flowering in summer after conifer pollen release had finished, heterospecific pollen deposited on these stigmas came mainly from other insect‐pollinated flowers, with little contribution from airborne conifer pollen. The results indicate that there might be little interference with coflowering angiosperms by airborne pollen from dominant conifers in natural communities.
Although mountain ranges are often recognized as global biodiversity hotspots with a high level of endemism, diversity and biogeographic connections of isolated and weakly explored mountains remain poorly understood. This is also the case for Shirkuh Mts. in central Iran. Here, Yazdana shirkuhensis gen. & spec. nov. (Caryophylleae, Caryophyllaceae) is described and illustrated from the high alpine zone of this mountain. Molecular phylogenetic analyses of nuclear and plastid DNA sequence data show that Y. shirkuhensis is related to Cyathophylla and Heterochroa (tribe Caryophylleae). The newly described genus and species accentuate Shirkuh Mts. as a center of endemism, which harbors a high number of narrowly distributed species, mostly in high elevations reaching alpine habitats. As this area is currently not protected, a conservation priority is highlighted for high elevations of Shirkuh Mts.
We present here the earliest known Asian fossil records of the Menispermaceae based on fossil fruits from Paleocene and Eocene localities in South China. A new genus and species, Paleoorbicarpum parvum sp. nov., and two new species of Stephania Loureiro, S. ornamenta sp. nov. and S. geniculata sp. nov., are recognized from Paleocene deposits of the Sanshui Basin, Guangdong, and a new occurrence of the widespread Eocene species Stephania auriformis (Hollick) Han & Manchester is recognized from the Maoming Basin, Guangdong. The Paleocene Stephania specimens described here represent the earliest fossil endocarp record of the Menispermaceae in eastern Asia. This discovery shows that the moonseed family had arrived in tropical and humid South China by at least the middle Paleocene, which provides important evidence for the origin and phytogeographic history of the family.
