Systematics and evolution of the needle grasses (Poaceae: Pooideae: Stipeae) based on analysis of multiple chloroplast loci, ITS, and lemma micromorphology

27 p.We conducted a molecular phylogenetic study of the tribe Stipeae using nine plastid DNA sequences (trnK-matK, matK, trnH-psbA, trnL-F, rps3, ndhF, rpl32-trnL, rps16-trnK, rps16 intron), the nuclear ITS DNA regions, and micromorphological characters from the lemma surface. Our large original dataset includes 156 accessions representing 139 species of Stipeae representing all genera currently placed in the tribe. The maximum likelihood and Bayesian analyses of DNA sequences provide strong support for the monophyly of Stipeae; including, in phylogenetic order, Macrochloa as remote sister lineage to all other Stipeae, then a primary stepwise divergence of three deep lineages with a saw-like (SL) lemma epidermal pattern (a plesiomorphic state). The next split is between a lineage (SL1) which bifurcates into separate Eurasian and American clades, and a lineage of three parts; a small Patis (SL2) clade, as sister to Piptatherum s.str. (SL3), and the achnatheroid clade (AC). The AC exhibits a maize-like lemma epidermal pattern throughout. AC consists of a core clade of Austral-Eurasian distribution and a “major American clade” of North and South American distribution. The base chromosome number for Stipeae is somewhat ambiguous but based on our survey it seems most likely to be x = 11 or 12. Our phylogenetic hypothesis supports the recognition of the following genera and groups (listed by region): Eurasia—Achnatherum, “Miliacea group”, “Neotrinia” (monotypic), Orthoraphium (monotypic), Patis (also 1 from North America), Piptatherum s.str., Psammochloa (monotypic), Ptilagrostis, Stipa, “Timouria group”, and Trikeraia; Mediterranean—Ampelodesmos (monotypic), Celtica (monotypic), Macrochloa (monotypic), and “Stipella-Inaequiglumes group”; Australasia —Anemanthele (monotypic), and Austrostipa; North America (NA)—“Eriocoma group”, Hesperostipa, Oryzopsis (monotypic), Piptatheropsis, “Pseudoeriocoma group”, and “Stillmania” (monotypic); South America—Aciachne, Amelichloa (also NA), Anatherostipa (s.str.), Jarava (polyphyletic), Lorenzochloa, Nassella (also NA), Ortachne, Pappostipa (also NA), and Piptochaetium (also NA). Monophyly of Phaenospermateae including Duthieinae is demonstrated, and its inclusion within or treatment as sister to Stipeae is rejected.Peer reviewe

Systematics of the Arctioid group: Disentangling Arctium and Cousinia (Cardueae, Carduinae)

16p. Incluye suplemento que contiene: Appendix 2. Species examined. Taxon, origin and voucher information. [http://www.ingentaconnect.com/content/iapt/tax/2011/00000060/00000002/art00020/supp-data/11677lopezsuppl][EN] We investigated the phylogeny of the Arctioid lineage of the Arctium-Cousinia complex in an attempt to clarify the conflictive generic boundaries of Arctium and Cousinia. The study was based on analyses of one nuclear (ITS) and two chloroplastic (trnL-trnT-rps4, rpl32-trnL) DNA regions of 37 species and was complemented with morphological evidence where possible. Based on the results, a broadly redefined monophyletic genus Arctium is proposed. The subgenera Hypacanthodes and Cynaroides are not monophyletic and are suppressed. In contrast, the traditional sectional classification of the genus Cousinia is maintained. The genera Anura, Hypacanthium and Schmalhausenia are reduced to sectional level.Peer reviewe

11677_Lopez.indd

Abstract We investigated the phylogeny of the Arctioid lineage of the Arctium-Cousinia complex in an attempt to clarify the conflictive generic boundaries of Arctium and Cousinia. The study was based on analyses of one nuclear (ITS) and two chloroplastic (trnL-trnT-rps4, rpl32-trnL) DNA regions of 37 species and was complemented with morphological evidence where possible. Based on the results, a broadly redefined monophyletic genus Arctium is proposed. The subgenera Hypacanthodes and Cynaroides are not monophyletic and are suppressed. In contrast, the traditional sectional classification of the genus Cousinia is maintained. The genera Anura, Hypacanthium and Schmalhausenia are reduced to sectional level

Phylogenetics of Piptatherum s.l. (Poaceae: Stipeae): Evidence for a new genus, Piptatheropsis, and resurrection of Patis.

14p. Tablas, fotografías b/n, apéndice.[EN]Historically, there has been taxonomic confusion among agrostologists regarding the short-spikeleted Stipeae. We refer to these as the Oryzopsis/Piptatherum complex which consists of short-spikeleted species with coriaceous to cartilaginous and often caducous-awned lemmas, and florets with a blunt callus. We conducted a phylogenetic analysis of 53 species that have been associated with this complex using four plastid regions (ndhF, rpl32-trnL, rps16-trnK, rps16 intron) in combination with lemma micromorphology to infer evolutionary relationships. Piptatherum as currently circumscribed is polyphyletic and is found in five strongly supported clades in our maximum likelihood tree. Based on our phylogenetic and morphological evidence we recognize a Eurasian Piptatherum s.str., propose a new genus, Piptatheropsis, to include five North American species, and resurrect the genus Patis to include three species, two from Eurasia and one from North America. We provide morphological descriptions of Patis, Piptatherum, and Piptatheropsis, and provide keys to the genera and species of the Oryzopsis/Piptatherum complex. The following new combinations are made: Patis obtusa, Patis racemosa, Piptatheropsis canadensis, Piptatheropsis exigua, Piptatheropsis micrantha, Piptatheropsis pungens, Piptatheropsis shoshoneana, Piptatherum brachycladum, and Piptatherum kopetdagense.We thank the following organizations and people: the Smithsonian Institution’s Restricted Endowment Fund, the Scholarly Studies Program, Research Opportunities, Atherton Seidell Foundation, Biodiversity Surveys and Inventories Program, National Museum of Natural History-Small Grants, and Laboratory of Analytical Biology (LAB) all for financial support; Lee Weigt, Gabriel Johnson, Jeffrey Hunt, David Erickson, Kenneth Wurdack, and Andrea Ormon for support and consultation while working at LAB; the National Geographic Society Committee for Research and Exploration (grant number 8087-06) for field and laboratory support; the Fulbright Scholar Program to KR for a research visit to the Smithsonian Institution.Peer reviewe

Extreme environmental conditions and phylogenetic inheritance: systematics of Myopordon and Oligochaeta (Asteraceae, Cardueae-Centaureinae)

The genus Myopordon, with six perennial species from Iran, Lebanon, Syria and Turkey, had until recently been placed in the Carduinae subtribe. Oligochaeta, composed of four annual species from the Caucasus, India, the Near East and Pakistan, was considered related to the genus Rhaponticum in the Centaureinae subtribe. The two genera have apparently not much in common; however, evidence that both are closely related within the Rhaponticum group was provided by recent molecular phylogenetic reconstructions. New and previously published cytogenetical (fluorescent in situ hybridization of rDNA genes, fluorochrome banding of AT- and GC-rich regions, silver nitrate staining of active ribosomal genes, genome size assessment), karyological, molecular phylogenetic and palynological data are evaluated in the light of the recent evidence concerning the relationships of Myopordon and Oligochaeta. Myopordon presents a constant chromosome number and a homogeneous pattern in physical mapping of rDNA genes, contrasting with a strong variability in chromosome banding, genome size and pollen-type. Such tendencies could be related to the environmental pressures in the high mountains where species of Myopordon occur. This also accords well with the phylogeny and the geographic distribution of the genus. Phylogenetic reconstructions resolve Oligochaeta as being nested in the clade of Myopordon species. The exceptional cytogenetical, karyological, as well as palynological characters of Oligochaeta are apparently derived from a Myopordon-like ancestor.This work was subsidized by the Ministerio de Educación y Ciencia, Spain (Project MEC CGL2004-04563-C02-01/BOS) and Generalitat de Catalunya ("Ajuts a Grups de Recerca Consolidats" 2005SGR00344). O. Hidalgo benefited from a pre-doctoral grant from the Ministerio de Educación y Ciencia (Spanish Government).Peer reviewe

A phylogeny of Poeae chloroplast group 1 including genera in the Agrostidinae, Anthoxanthinae, Aveninae, Brizinae, Calothecinae, Echinopogoninae, Phalaridinae, and Torreyochloinae (Poaceae: Pooideae)

Trabajo presentado en el 6th International Conference on Comparative Biology of Monocotyledons- Monocots VI, celebrado en Natal (Brasil), del 7 al 12 de octubre de 2018Peer reviewe

Lessons from Plectocephalus (Compositae, Cardueae-Centaureinae): ITS disorientation in annuals and Beringian dispersal as revealed by molecular analyses

-Background and Aims: The geographic distribution of the genus Plectocephalus comprises a single species in Ethiopia, two in North America and possibly four more in South America, in a striking disjunction that is exceptional for genera of the tribe Cardueae. The enormity of this disjunction cast doubts on the precise taxonomic delineation of the genus, which is not unanimously recognized as a natural entity. Our aims were to define the generic boundaries of Plectocephalus and to formulate a hypothesis that would explain its natural range. -Methods: A combined molecular approach, using nuclear ITS and ETS and plastid trnL-trnL-F, rpl32-trnLUAG and ndhF markers, was chosen for phylogenetic reconstruction by maximum parsimony and Bayesian inference. Key Results: Phylogenetic analysis shows that Plectocephalus is a natural genus that includes the African species P. varians, together with all the native South American species, currently classified as Centaurea, C. cachinalensis, C. floccosa and C. tweediei. The recognition of Centaurodendron as an independent genus, which we consider appropriate, would make Plectocephalus paraphyletic. Affinities of Plectocephalus should lie with eastern representatives of Centaureinae. Geographic disjunction is explained as a consequence of dispersal via the Bering Land Bridge during the Miocene-Pliocene. The phylogeny of the basal grade of Centaureinae differs from previous phylogenies, and artifacts resulting from differences in mutation rates of annual and perennial taxa are confirmed. Sensitivity of ITS to these differences was the highest observed for all DNA regions used in this study. Conclusions: The natural status of the genus Plectocephalus is confirmed and several nomenclatural combinations are proposed. New evidence contributes to the debate concerning problems posed by the use of ITS in the phylogenetic reconstruction of groups that differ in terms of their life cycles. Dispersal from the Caucasus and Anatolia along the Siberian route and then across the Bering Land Bridge follows a route previously proposed for other taxonomic groups.This work was supported by the Ministry of Science and Innovation of Spain [projects CGL2006-01765/BOS and CGL2009-13322-C03-03] and the Generalitat de Catalunya ["Ajuts a Grups de Recerca Consolidats" 2009-SGR-439].Peer reviewe

Miocene–Pliocene speciation, introgression, and migration of Patis and Ptilagrostis (Poaceae: Stipeae)

16 p., gráf., tablasGenetic interchange between American and Eurasian species is fundamental to our understanding of the biogeographical patterns, and we make a first attempt to reconstruct the evolutionary events in East Asia that lead to the origin and dispersal of two genera, Patis and Ptilagrostis. We conducted a molecular phylogenetic study of 78 species in the tribe Stipeae using four plastid DNA sequences (ndhF, rpl32-trnL, rps16-trnK, and rps16 intron) and two nuclear DNA sequences (ITS and At103). We use single copy nDNA gene At103 for the first time in the grasses to elucidate the evolutionary history among members of the Stipeae. Ampelodesmos, Hesperostipa, Oryzopsis, Pappostipa, Patis, and Stipa are found to be of multiple origins. Our phylograms reveal conflicting positions for Ptilagrostis alpina and Pt. porteri that form a clade with Patis coreana, P. obtusa, and P. racemosa in the combined plastid tree but are aligned with other members of Ptilagrostis in the ITS tree. We hypothesize that Ptilagrostis still retains the nucleotype of an extinct genus which transited the Bering land bridge from American origins in the late Miocene (minimum 7.35–6.37 mya) followed by hybridization and two plastid capture events with a Trikeraia-like taxon (7.96 mya) and para-Patis (between 5.32 and 3.76 mya). Ptilagrostis porteri and Patis racemosa then migrated to continental North America 1.7–2.9 mya and 4.3–5.3 mya, respectively.This project was funded by the Restricted Endowment Fund, the Scholarly Studies Program, Research Opportunities, Atherton Seidell Foundation, Biodiversity Surveys and Inventories Program, National Museum of Natural History-Small Grants, and Laboratory of Analytical Biology (LAB) all part of the Smithsonian Institution. We thank the National Geographic Society Committee for Research and Exploration (Grant Number 8087-06) for field and laboratory support and the Fulbright Scholar Program to KR for a research visit to the Smithsonian Institution.Peer reviewe

Phylogeny of the Centaurea group (Centaurea, Compositae) – Geography is a better predictor than morphology

21 p., tablas, gráf.The Centaurea group is part of the Circum-Mediterranean Clade (CMC) of genus Centaurea subgenus Centaurea, a mainly Mediterranean plant group with more than 200 described species. The group is traditionally split on morphological basis into three sections: Centaurea, Phalolepis and Willkommia. This division, however, is doubtful, especially in light of molecular approaches. In this study we try to resolve this phylogenetic problem and to consolidate the circumscription and delimitation of the entire group against other closely related groups. We analyzed nuclear (internal transcribed spacer of the ribosomal genes) and chloroplast (rpl32-trnL intergenic spacer) DNA regions for most of the described species of the Centaurea group using phylogenetic and network approaches, and we checked the data for recombination. Phylogeny was used to reconstruct the evolution of the lacerate-membranaceous bract appendages using parsimony. The magnitude of incomplete lineage sorting was tested estimating the effective population sizes. Molecular dating was performed using a Bayesian approach, and the ancestral area reconstruction was conducted using the Dispersal–Extinction–Cladogenesis method. Monophyly of the Centaurea group is confirmed if a few species are removed. Our results do not support the traditional sectional division. There is a high incongruence between the two markers and between genetic data and morphology. However, there is a clear relation between geography and the structure of the molecular data. Diversification in the Centaurea group mainly took place during the Pliocene and Pleistocene. The ancestral area infered for the Circum-Mediterranean Clade of Centaurea is the Eastern Mediterranean, whereas for the Centaurea group it is most likely NW-Africa. The large incongruencies, which hamper phylogenetic reconstruction, are probably the result of introgression, even though the presence of incomplete lineage sorting as an additional factor cannot be ruled out. Convergent evolution of morphological traits may have led to incongruence between morphology-based, traditional systematics and molecular results. Our results also cast major doubts about current species delimitation.Financial support from the Spanish Ministry of Science and Innovation (Projects CGL2007-60781/BOS and CGL2010-18631) and the Generalitat de Catalunya (Ajuts a Grups de Recerca Consolidats 2009/SGR/00439) is gratefully acknowledged. AH benefited from a predoctoral grant of the JAE program of the CSIC. The collection of Turkish species was funded by the BAP (Scientific Researching Projects of Selçuk University) project with number 06401023.Peer reviewe