The phylogeny of Patrinieae sensu Graebner (Valerianaceae) revisited: additional evidence from ndhF sequence data

 DNA sequences of both 5′ and 3′ regions of the plastid ndhF gene were generated in order to study the position of Patrinia and Nardostachys, to check the potential paraphyletic nature of Patrinieae, and to evaluate the possible link between the tribe and Linnaeaceae. Parsimony analysis showed very strong support for Patrinia as sister to all members of Valerianaceae (including Nardostachys) and indicated the paraphyletic nature of the tribe Patrinieae. Additionally, trees were constructed from available rbcL data separately and supplemented with ndhF sequences. Topologies of these combined cladograms are in agreement with the ndhF phylogeny, suggesting that the traditionally circumscribed Patrinieae can no longer be recognized but must be considered as part of a basal grade in Valerianaceae. Parsimony analysis based on a morphological data set supported a monophyletic Patrinieae; combination with the molecular data showed a paraphyletic Patrinieae. Furthermore, the possible link between Patrinieae and Linnaeaceae is evaluated. Received July 12, 2001 Accepted February 25, 2002     

Phylogenetics of Escallonia (Escalloniaceae) based on plastid DNA sequence data

Escallonia (Escalloniaceae) is a New World genus of c. 39 species distributed mainly in the South American highlands. Plastid DNA sequence data from the intergenic spacers trnS‐trnG and 3′ trnV‐ndhC and the ndhF gene for 32 species were used to examine the relationships among species and related genera and to analyse the relationship between phylogeny and the geographical distribution of the species. Maximum parsimony and Bayesian inference were employed to analyse the data. The sister relationship of Escallonia to Forgesia and Valdivia was corroborated. We recovered five strongly supported clades that are geographically structured, suggesting that the evolutionary history of the genus may be linked to historical processes, including the uplift of mountainous systems in South America. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173 , 442–451.     

Phylogenetics and biogeography of eastern Asian-North American disjunct genus Pachysandra （Buxaceae） inferred from nucleotide sequences

Pachysandra is an eastern Asian-North American disjtunct genus with three species, two in eastern Asia （Pachysandra axillaris and Pachysandra terminalis） and one in eastern North America （Pachysandra procurnbens）. Although morphological and cytological studies suggest a close affinity of Pprocumbens with P axillaris, molecular data from nuclear and chloroplast DNA regions have provided conflicting signals. In this study, we tested previous phylogenetic hypotheses using sequences of nuclear ribosomal DNA internal transcribed spacers and chloroplast ndhF gene from multiple individuals of each of the three species. We also estimated the time of divergence between eastem Asia and eastern North America. Our results support the morphological and cytological conclusion that P procumbens is more closely related to P axillaris than to P terminalis. The estimated time of divergence of P axillaris and P procumbens was 14.6±5.5 mya, consistent with estimates from many other eastern Asian-North American disjunct genera. The migration of Pachysandra populations from eastern Asia to North America might have occurred by way of the North Atlantic land bridge.     

Phylogeny of the core Malvales: evidence from ndhF sequence data

The monophyly of the group comprising the core malvalean families, Bombacaceae, Malvaceae, Sterculiaceae, and Tiliaceae, was recently confirmed by molecular studies, but the internal structure of this clade is poorly understood. In this study, we examined sequences of the chloroplast ndhF gene (aligned length 2226 bp) from 70 exemplars representing 35 of the 39 putative tribes of core Malvales. The monophyly of one traditional family, the Malvaceae, was supported in the trees resulting from these data, but the other three families, as traditionally circumscribed, are nonmonophyletic. In addition, the following relationships were well supported: (1) a clade, /Malvatheca, consisting of traditional Malvaceae and Bombacaceae (except some members of tribe Durioneae), plus Fremontodendron and Chiranthodendron, which are usually treated as Sterculiaceae; (2) a clade, /Malvadendrina, supported by a unique 21-bp (base pair) deletion and consisting of /Malvatheca, plus five additional subclades, including representatives of Sterculiaceae and Tiliaceae, and Durionieae; (3) a clade, /Byttneriina, with genera traditionally assigned to several tribes of Tiliaceae, plus exemplars of tribes Byttnerieae, Hermannieae, and Lasiopetaleae of Sterculiaceae. The most striking departures from traditional classifications are the following: Durio and relatives appear to be more closely related to Helicteres and Reevesia (Sterculiaceae) than to Bombacaceae; several genera traditionally considered as Bombacaceae (Camptostemon, Matisia, Phragmotheca, and Quararibea) or Sterculiaceae (Chiranthodendron and Fremontodendron) appear as sister lineages to the traditional Malvaceae; the traditional tribe Helictereae (Sterculiaceae) is polyphyletic; and Sterculiaceae and Tiliaceae, as traditionally circumscribed, represent polyphyletic groups that cannot sensibly be maintained with their traditional limits for purposes of classification. We discuss morphological characters and conclude that there has been extensive homoplasy in characters previously used to delineate major taxonomic groups in core Malvales. The topologies here also suggest that /Malvatheca do not have as a synapormophy monothecate anthers, as has been previously supposed but, instead, may be united by dithecate, transversely septate (polysporangiate) anthers, as found in basal members of both /Bombacoideae and /Malvoideae. Thus, “monothecate” anthers may have been derived at least twice, independently, within the /Bombacoideae (core Bombacaceae) and /Malvoideae (traditional Malvaceae).     

Phylogeny and biogeography of the genus Ainsliaea (Asteraceae) in the Sino-Japanese region based on nuclear rDNA and plastid DNA sequence data

BACKGROUND AND AIMS: The flora of the Sino-Japanese plant region of eastern Asia is distinctively rich compared with other floristic regions in the world. However, knowledge of its floristic evolution is fairly limited. The genus Ainsliaea is endemic to and distributed throughout the Sino-Japanese region. Its interspecific phylogenetic relationships have not been resolved. The aim is to provide insight into floristic evolution in eastern Asia on the basis of a molecular phylogenetic analysis of Ainsliaea species. METHODS: Cladistic analyses of the sequences of two nuclear (ITS, ETS) and one plastid (ndhF) regions were carried out individually and using the combined data from the three markers. KEY RESULTS: Phylogenetic analyses of three DNA regions confirmed that Ainsliaea is composed of three major clades that correspond to species distributions. Evolution of the three lineages was estimated to have occurred around 1.1 MYA during the early Pleistocene. CONCLUSIONS: The results suggest that Ainsliaea species evolved allopatrically and that the descendants were isolated in the eastern (between SE China and Japan, through Taiwan and the Ryukyu Islands) and western (Yunnan Province and its surrounding areas, including the Himalayas, the temperate region of Southeast Asia, and Sichuan Province) sides of the Sino-Japanese region. The results suggest that two distinct lineages of Ainsliaea have independently evolved in environmentally heterogeneous regions within the Sino-Japanese region. These regions have maintained rich and original floras due to their diverse climates and topographies.     

Interspecific delimitation and phylogenetic origin of Pugionium(Brassicaceae)

Pugionium(Brassicaceae)is a small genus that occurs in central Asian deserts.The interspecific delimitation and taxonomic treatments of this genus are disputed and its phylogenetic origin remains unknown. In the present study,we examined these issues based on morphological and molecular data obtained for the first time.We used statistical methods to examine inter-and intraspecific morphological variations.The results suggest that only two species,namely P.dolabratum and P.cornutum,can be warranted for all examined populations and specimens,whereas three species(P.calcaratum,P.cristatum,and P.pterocarpum)should be incorporated into P. dolabratum.This delimitation was further supported by the molecular data:all populations of P.dolabratum,P. calcaratum,P.cristatum,and P.pterocarpum shared the same internal transcribed spacer genotype,whereas those from P.cornutum had another type.Phylogenetic analyses of Pugionium and representative genera of Brassicaceae based on ndhF sequences suggest that this genus is sister to the genus Megacarpaea,which,together,comprise a well-supported lineage with Farsetia,Lobularia,Iberis,and Ionopsidium,whereas the two other genera that were previously suggested to be closely related to this genus(Isatis and Bunias)were placed in the other lineages.We further discuss the origin of Pugionium and suggest that it probably originated in central Asia when the climate became drier from the late Miocene.     

The asteralean affinity of the Mauritian Roussea (Rousseaceae)

Roussea , a monotypic genus endemic to Mauritius, has for a long time been associated with Brexia (Celastraceae). Recently, it has been shown that Roussea is placed correctly in the mainly Australasian Asterales, but the sister group to Roussea has not been unequivocally identified. Cladistic analysis of the chloroplast genes ndhF and rbcL identifies the sister group to.Roussea as Carpodetaceae. Recognizing this relationship, the monotypic Rousseaceae is merged with Carpodetaceae into Rousseaceae s.l. comprising two subfamilies. This group is characterized by many-locular ovaries and similarities in the appearance of the petals. Rousseaceae s.l. exhibit a disjunct distribution in Mauritius, East Australia, New Zealand and New Guinea     

Polemoniaceae phylogeny and classification: implications of sequence data from the chloroplast gene ndhF

The chloroplast gene ndhF was used to study phylogenetic relationships of the Polemoniaceae at two levels: among members of the Ericales and among genera of the family. Sequence data for interfamilial analyses consisted of 2266 bp for 14 members of the Ericales, including four species of the Polemoniaceae, plus three outgroup taxa. The Polemoniaceae were found to be related to Diospyros, Fouquieria, the Primulales, Rhododendron, and Impatiens, but relationships among taxa were generally not well supported. The precise position of the Polemoniaceae within the Ericales remains obscure. Data for intrafamilial analyses consisted of 1031 bp for 27 species of the Polemoniaceae, including at least one species from most genera of the family, plus five outgroup taxa. A single most parsimonious tree was identified. The analyses suggested that subfamily Cobaeoideae, excluding Loeselia, is monophyletic and that Huthia is sister to Cantua. Acanthogilia was sister to the remainder of subfamily Cobaeoideae. Subfamily Polemonioideae plus Loeselia formed four subclades that were strongly supported as monophyletic and represent the major lineages of the subfamily.     

Phylogenetic analysis of Magnoliales and Myristicaceae based on multiple data sets: implications for character evolution

Magnoliales, consisting of six families of tropical to warm-temperate woody angiosperms, were long considered the most archaic order of flowering plants, but molecular analyses nest them among other eumagnoliids. Based on separate and combined analyses of a morphological matrix (115 characters) and multiple molecular data sets (seven variable chloroplast loci and five more conserved genes; 14 536 aligned nucleotides), phylogenetic relationships were investigated simultaneously within Magnoliales and Myristicaceae, using Laurales, Winterales, and Piperales as outgroups. Despite apparent conflicts among data sets, parsimony and maximum likelihood analyses of combined data converged towards a fully resolved and well-supported topology, consistent with higher-level molecular analyses except for the position of Magnoliaceae: Myristicaceae + (Magnoliaceae + (( Degeneria + Galbulimima ) + ( Eupomatia + Annonaceae))). Based on these results, we discuss morphological evolution in Magnoliales and show that several supposedly plesiomorphic traits are synapomorphies of Magnoliineae, the sister group of Myristicaceae (e.g. laminar stamens). Relationships within Annonaceae are also resolved with strong support ( Anaxagorea basal, then ambavioids). In contrast, resolution of relationships within Myristicaceae is difficult and still incomplete, due to a very low level of molecular divergence within the family and a long stem lineage. However, our data provide good evidence that Mauloutchia is nested among other Afro-Malagasy genera, contradicting the view that its androecium and pollen are plesiomorphic  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 142 , 125–186.