scholarly journals Phylogenetic analyses of plastid DNA suggest a different interpretation of morphological evolution than those used as the basis for previous classifications of Dipterocarpaceae (Malvales)

2017 ◽  
Vol 185 (1) ◽  
pp. 1-26 ◽  
Author(s):  
Jacqueline Heckenhauer ◽  
Rosabelle Samuel ◽  
Peter S Ashton ◽  
Barbara Turner ◽  
Michael H J Barfuss ◽  
...  
Author(s):  
Jo&#227o A. N. Batista ◽  
Pablo B. Meyer ◽  
Gabriela Cruz-Lustre ◽  
Antonio L. V. Toscano de Brito

Habenaria longissima, a new species from the H. nuda species complex, is described and illustrated. It is remarkable for the exceptionally long lateral segments of the petals and labellum, which are the longest among Neotropical Habenaria, both in absolute and inproportional terms. Despite the morphological similarity, Bayesian and parsimony phylogenetic analyses based on nuclear (ITS) and plastid DNA markers (matK), revealed that H. longissima is distantly related to other species of the complex, and constitutes an independent lineage. Its distribution is unusual in that it is the only species of Orchidaceae restricted to the Quadrilátero Ferrífero in the State of Minas Gerais and to Chapada Diamantina, in the central part of the Espinhaço range in the State of Bahia, with the populations 1000 km from each other. Habenaria longissima is a rare species, known only from three localities and four populations and informally proposed as Endangered due to the small area of occupancy and small number of known populations.


Phytotaxa ◽  
2021 ◽  
Vol 484 (3) ◽  
pp. 291-297
Author(s):  
XINYU XU ◽  
CHANG-CHUN DING ◽  
WENQI HU ◽  
XIA YU ◽  
YU ZHENG ◽  
...  

A new species of Cymbidium (Orchidaceae), Cymbidium xichouense, from Yunnan Province, China, is described and illustrated based on morphological evidence and molecular analyses. The new orchid is morphologically similar to C. qinbeiense, but it has several morphological features that distinguish it from C. qiubeinense and all other recognized species in Cymbidium. Phylogenetic analyses based on nuclear (ITS) and plastid DNA (matK) were conducted, and the results also supported the status of C. xichouense as a new species, which is sister to C. qiubeiense.


2020 ◽  
Vol 194 (1) ◽  
pp. 84-99
Author(s):  
Inelia Escobar ◽  
Eduardo Ruiz-Ponce ◽  
Paula J Rudall ◽  
Michael F Fay ◽  
Oscar Toro-Núñez ◽  
...  

Abstract Gilliesieae are a South American tribe of Amaryllidaceae characterized by high floral diversity. Given different taxonomic interpretations and proposals for generic and specific relationships, a representative phylogenetic analysis is required to clarify the systematics of this group. The present study provides a framework for understanding phylogenetic relationships and contributing to the development of an appropriate taxonomic treatment of Gilliesieae. Molecular analyses, based on nuclear (ITS) and plastid DNA sequences (trnL-F and rbcL), resolve with strong support the monophyly of the tribe and the differentiation of two major clades. Clade I comprises the genera Gilliesia, Gethyum and Solaria and Clade II includes Miersia and Speea. These well-supported clades are mostly congruent with vegetative and karyotype characters rather than, e.g., floral symmetry. At the generic level, all molecular analyses reveal the paraphyly of Gilliesia and Miersia. Gethyum was found to be paraphyletic, resulting in the confirmation of Ancrumia as a distinct genus. Several instances of incongruent phylogenetic signals were found among data sets. The calibrated tree suggests a recent diversification of the tribe (Pliocene–Pleistocene), a contemporary process of speciation in which instances of hybridization and incomplete lineage sorting could explain patterns of paraphyly and incongruence of floral morphology.


Phytotaxa ◽  
2020 ◽  
Vol 428 (1) ◽  
pp. 67-72
Author(s):  
YAN-QIONG CHEN ◽  
YA-TING ZHU ◽  
HUI ZHONG ◽  
ZE-XIN LI ◽  
ZHONG-JIAN LIU ◽  
...  

A new orchid, Calanthe tsiana, is described from southeastern Yunnan, China, based on morphological and DNA evidence. In morphological comparisons, C. tsiana is similar to C. arisanensis, but it differs in having subspatulate petals and falcate-obovate lateral lobes of lip with one ridge on the disk. The phylogenetic analyses based on nuclear ribosomal ITS and plastid DNA (rbcL, matK and trnL-trnF) place C. tsiana with C. arisanensis as sister species and support C. tsiana as a new species.


2020 ◽  
Author(s):  
Saroj Ruchisansakun ◽  
Arne Mertens ◽  
Steven B Janssens ◽  
Erik F Smets ◽  
Timotheüs van der Niet

Abstract Background and Aims Floral diversity as a result of plant–pollinator interactions can evolve by two distinct processes: shifts between pollination systems or divergent use of the same pollinator. Although both are pollinator driven, the mode, relative importance and interdependence of these different processes are rarely studied simultaneously. Here we apply a phylogenetic approach using the Balsaminaceae (including the species-rich genus Impatiens) to simultaneously quantify shifts in pollination syndromes (as inferred from the shape and colour of the perianth), as well as divergent use of the same pollinator (inferred from corolla symmetry). Methods For 282 species we coded pollination syndromes based on associations between floral traits and known pollination systems, and assessed corolla symmetry. The evolution of these traits was reconstructed using parsimony- and model-based approaches, using phylogenetic trees derived from phylogenetic analyses of nuclear ribosomal and plastid DNA sequence data. Key Results A total of 71 % of studied species have a bee pollination syndrome, 22 % a bimodal syndrome (Lepidoptera and bees), 3 % a bird pollination syndrome and 5 % a syndrome of autogamy, while 19 % of species have an asymmetrical corolla. Although floral symmetry and pollination syndromes are both evolutionarily labile, the latter shifts more frequently. Shifts in floral symmetry occurred mainly in the direction towards asymmetry, but there was considerable uncertainty in the pattern of shift direction for pollination syndrome. Shifts towards asymmetrical flowers were associated with a bee pollination syndrome. Conclusion Floral evolution in Impatiens has occurred through both pollination syndrome shifts and divergent use of the same pollinator. Although the former appears more frequent, the latter is likely to be underestimated. Shifts in floral symmetry and pollination syndromes depend on each other but also partly on the region in which these shifts take place, suggesting that the occurrence of pollinator-driven evolution may be determined by the availability of pollinator species at large geographical scales.


Phytotaxa ◽  
2013 ◽  
Vol 152 (1) ◽  
pp. 59
Author(s):  
Karol Marhold ◽  
Petr Sklenář

Lasiocephalus Willd. ex Schlechtendal (1818: 308), as traditionally circumscribed (e.g., by Cuatrecasas 1978, Dušková et al. 2010), is a neotropical genus of ca 25 species confined to the Andes and distributed from Venezuela to Bolivia. Nevertheless, recent studies by Pelser et al. (2007, 2010) have shown that based on phylogenetic analyses of nrITS and plastid DNA sequence data, species of the genus Lasiocephalus are deeply embedded in Senecio Linnaeus (1753: 866), and, consequently, should be transferred into this latter genus. In fact, a number of species of Lasiocephalus were originally described as Senecio or had been, at some point, transferred into Senecio so only few transfers are necessary.


2004 ◽  
Vol 359 (1450) ◽  
pp. 1495-1508 ◽  
Author(s):  
J. E. Richardson ◽  
L. W. Chatrou ◽  
J. B. Mols ◽  
R. H. J. Erkens ◽  
M. D. Pirie

Annonaceae are a pantropically distributed family found predominantly in rainforests, so they are megathermal taxa, whereas Rhamnaceae are a cosmopolitan family that tend to be found in xeric regions and may be classified as mesothermal. Phylogenetic analyses of these families are presented based on rbcL and trn L–F plastid DNA sequences. Likelihood ratio tests revealed rate heterogeneity in both phylogenetic trees and they were therefore made ultrametric using non–parametric rate smoothing and penalized likelihood. Divergence times were then estimated using fossil calibration points. The historical biogeography of these families that are species rich in different biomes is discussed and compared with other published reconstructions. Rhamnaceae and most lineages within Annonaceae are too young to have had their distribution patterns influenced by break–up of previously connected Gondwanan landmasses. Contrasts in the degree of geographical structure between these two families may be explained by differences in age and dispersal capability. In both groups, long–distance dispersal appears to have played a more significant role in establishing modern patterns than had previously been assumed. Both families also contain examples of recent diversification of species–rich lineages. An understanding of the processes responsible for shaping the distribution patterns of these families has contributed to our understanding of the historical assembly of the biomes that they occupy.


Phytotaxa ◽  
2016 ◽  
Vol 269 (2) ◽  
pp. 69
Author(s):  
DMITAR LAKUŠIĆ ◽  
SAŠA STEFANOVIĆ ◽  
SONIA SILJAK-YAKOVLEV ◽  
TAMARA RAKIĆ ◽  
NEVENA KUZMANOVIĆ ◽  
...  

The taxonomically intricate Edraianthus dalmaticus-serbicus group within E. tenuifolius-complex in the Balkan Peninsula is reviewed using morphological, molecular and genome size data based on extensive sampling of populations across the species’ range. The phylogenetic analyses based on Amplified Fragment Length Polymorphisms (AFLPs), plastid DNA (trnL-F region and rbcL-atpB spacer) and nuclear ribosomal external transcribed spacer (nrETS) sequences confirmed the monophyly of E. serbicus as traditionally defined but have also revealed the presence of two distinct and allopatrically distributed taxa. The genome size and morphological analyses, performed on the same widespread sample of populations, largely corresponded with molecular results, allowing us to raise the overlooked taxon E. serbicus subsp. stankovici, to the species level. The names Edraianthus serbicus and E. serbicus subsp. stankovicii (≡ E. stankovicii) are typified. Furthermore, a new differential diagnosis, description and illustration of E. stankovicii are provided, as well as its conservation status is assessed. Edraianthus stankovicii is a rare and critically endangered stenoendemic taxon, with the distribution limited only to Mts. Veliki Krš and Stol in NE Serbia.


2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Michelle R. Stocker ◽  
Li-Jun Zhao ◽  
Sterling J. Nesbitt ◽  
Xiao-Chun Wu ◽  
Chun Li

Abstract Following the end-Permian extinction, terrestrial vertebrate diversity recovered by the Middle Triassic, and that diversity was now dominated by reptiles. However, those reptilian clades, including archosaurs and their closest relatives, are not commonly found until ~30 million years post-extinction in Late Triassic deposits despite time-calibrated phylogenetic analyses predicting an Early Triassic divergence for those clades. One of these groups from the Late Triassic, Phytosauria, is well known from a near-Pangean distribution, and this easily recognized clade bears an elongated rostrum with posteriorly retracted nares and numerous postcranial synapomorphies that are unique compared with all other contemporary reptiles. Here, we recognize the exquisitely preserved, nearly complete skeleton of Diandongosuchus fuyuanensis from the Middle Triassic of China as the oldest and basalmost phytosaur. The Middle Triassic age and lack of the characteristically-elongated rostrum fill a critical morphological and temporal gap in phytosaur evolution, indicating that the characteristic elongated rostrum of phytosaurs appeared subsequent to cranial and postcranial modifications associated with enhanced prey capture, predating that general trend of morphological evolution observed within Crocodyliformes. Additionally, Diandongosuchus supports that the clade was present across Pangea, suggesting early ecosystem exploration for Archosauriformes through nearshore environments and leading to ease of dispersal across the Tethys.


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