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The article presents a molecular phylogenetic analysis of nuclear ribosomal internal transcribed spacer (nrITS) and chloroplast deoxyribonucleic acid (cpDNA) sequences of the genus Pleurospermum s. 1. Umbelliferae--Apioideae, and a comparison with an analysis of its morphological characters. Based on molecular data, no confirmation was made of an early divergence between the Pleurospermum northern and Sino-Himalayan species.

Abstract: Phylogenetic relationships in the genus Anthyllis (Leguminosae: Papilionoideae: Loteae) were investigated using data from the nuclear ribosomal internal transcribed spacer regions (ITS) and three plastid regions (psbA–trnH intergenic spacer, petB–petD region and rps16 intron). Bayesian and maximum parsimony (MP) analysis of a concatenated plastid dataset recovered well-resolved trees that are topologically similar, with many clades supported by unique indels. MP and Bayesian analyses of the ITS sequence data recovered trees that have several well-supported topological differences, both among analyses, and to trees inferred from the plastid data. The most substantial of these concerns A. vulneraria and A. lemanniana, whose placement in the parsimony analysis of the ITS data appears to be due to a strong long-branch effect. Analysis of the secondary structure of the ITS1 spacer showed a strong bias towards transitions in A. vulneraria and A. lemanniana, many of which were also characteristic of certain outgroup taxa. This may contribute to the conflicting placement of this clade in the MP tree for the ITS data. Additional conflicts between the plastid and ITS trees were more taxonomically focused. These differences may reflect the occurrence of reticulate evolution between closely related species, including a possible hybrid origin for A. hystrix. The patterns of incongruence between the plastid and the ITS data seem to correlate with taxon ranks. All of our phylogenetic analyses supported the monophyly of Anthyllis (incl. Hymenocarpos). Although they are often taxonomically associated with Anthyllis, the genera Dorycnopsis and Tripodion are shown here to be more closely related to other genera of Loteae. We infer up to six major clades in Anthyllis that are morphologically well-characterized, and which could be recognized as sections. Four of these agree with various morphology-based classifications, while the other two are novel. We reconstruct the evolution of several morphological characteristics found only in Anthyllis or tribe Loteae. Some of these characters support major clades, while others show evidence of homoplasy within Anthyllis. [Copyright &y& Elsevier]

Abstract: The Umbelliferae is a large and taxonomically complex family of flowering plants whose phylogenetic relationships, particularly at low taxonomic levels, are generally obscure based on current and widely used molecular markers. Thus, information on the phylogenetic utility of additional molecular markers at these levels is highly favorable. We investigate the utility of nuclear ribosomal DNA (nrDNA) external transcribed spacer (ETS) sequences for phylogenetic inference in Umbelliferae tribe Tordylieae, a group whose relationships have been previously difficult to resolve owing to low sequence variability, and compare the results to those obtained from the nrDNA internal transcribed spacer (ITS) region. We report that the ETS region evolves at a slightly faster rate and has a higher percentage of parsimony informative characters than that of ITS and all chloroplast DNA loci examined to date. The ETS region is a valuable phylogenetic marker in Umbelliferae for low level analysis, especially when used in combination with ITS. [Copyright &y& Elsevier]