Herbarium, ALA, University of Alaska Museum of the North and Dept. of Biology and Wildlife, University of Alaska, Fairbanks, Fairbanks, AK 99775, USA.
Mol Phylogenet Evol. 2013 Jun;67(3):589-99. doi: 10.1016/j.ympev.2013.02.020. Epub 2013 Feb 26.
We investigated the evolutionary complexity that resulted from cryptic diversification and polyploidy in parsley ferns (Cryptogramma). A total of 14 species were included in our data set, with six outgroup species and eight Cryptogramma species. DNA sequence data from six plastid loci (rbcL, rbcL-accD, rbcL-atpB, rps4-trnS, trnG-trnR and trnP-petG) were analyzed using maximum likelihood and Bayesian methods to provide the first rigorous assessment of diversification in the genus, including testing the monophyly of the genus and sections. Cryptogramma and Coniogramme are recovered as reciprocally monophyletic sister genera. We established the monophyly of both sections within Cryptogramma. Furthermore, our sequence data reveal that described species reflect mostly allopatric reciprocally monophyletic lineages that are independent evolutionary trajectories. Using sequence data from the nuclear locus (gapCp) we find that the European C. crispa is an autotetraploid with a partially diploidized genome, while the North American tetraploid Cryptogramma sitchensis is an allopolyploid derived from C. acrostichoides and C. raddeana. Subsequent backcrossing between C. sitchensis and C. acrostichoides has allowed the introgression of C. raddeana alleles into northern populations of C. acrostichoides.
我们研究了隐秘多样化和多倍体在欧芹蕨（Cryptogramma）中产生的进化复杂性。我们的数据集中共包括 14 个物种，其中 6 个为外群物种，8 个为 Cryptogramma 物种。利用最大似然法和贝叶斯法对来自 6 个质体基因座（rbcL、rbcL-accD、rbcL-atpB、rps4-trnS、trnG-trnR 和 trnP-petG）的 DNA 序列数据进行了分析，从而首次对该属的多样化进行了严格评估，包括检验该属和各亚属的单系性。结果显示，Cryptogramma 和 Coniogramme 被恢复为互为单系的姊妹属。我们确立了 Cryptogramma 内各亚属的单系性。此外，我们的序列数据表明，描述的物种主要反映了相互隔离的单系谱系，这些谱系是独立的进化轨迹。利用核基因座（gapCp）的序列数据，我们发现欧洲的 C. crispa 是一个部分二倍体化的同源四倍体，而北美四倍体的 Cryptogramma sitchensis 则是源自 C. acrostichoides 和 C. raddeana 的异源四倍体。随后，C. sitchensis 与 C. acrostichoides 之间的回交允许 C. raddeana 等位基因渗入到 C. acrostichoides 的北部种群中。
