id:"swepub:oai:DiVA.org:su-126873"
Search: id:"swepub:oai:DiVA.org:su-126873" > DISENTANGLING THE P...
- 1 of 1
- Previous record
- Next record
- To hitlist
DISENTANGLING THE PHYLOGENY OF ISOETES (ISOETALES), USING NUCLEAR AND PLASTID DATA
-
- Larsén, Eva (author)
- Stockholms universitet,Institutionen för ekologi, miljö och botanik
-
- Rydin, Catarina (author)
- Stockholms universitet,Institutionen för ekologi, miljö och botanik
- (creator_code:org_t)
- University of Chicago Press, 2016
- 2016
- English.
- In: International journal of plant sciences. - : University of Chicago Press. - 1058-5893 .- 1537-5315. ; 177:2, s. 157-174
- Journal article (peer-reviewed)
Abstract
Subject headings
Close
- Premise of research. The heterosporous lycopsids of Isoetes show limited morphological and genetic variation despite a worldwide distribution and the ancient origin of the lineage. Here major relationships within the genus are clarified, using a substantially larger sampling of species than in previous studies. A first assessment of divergence times of clades is made, and the implications for dispersal mechanisms and biogeographic distribution patterns are discussed. Methodology. On the basis of sequences from three gene regions and 109 specimens representing 74 species of Isoetes, phylogeny and node ages were estimated using parsimony and Bayesian inference. Pivotal results. Three rooting approaches (outgroup analysis, midpoint rooting, and clock rooting) coherently resolved a diverse clade containing species from South Africa, India, Australia, and South America (clade A) as sister to remaining Isoetes. Analysis of divergence times of clades yielded a median age of the crown group of 147 million years ago (mya) using a birth-death tree prior and 165 mya using a Yule tree prior. Clade A was dated to 111 or 125 mya, respectively. While the earliest divergences in Isoetes appear readily explained by ancient vicariance, patterns in younger clades are consistent with dispersal processes, sometimes over long distances. Isoetes andicola (Amstutz) L.D. Gomez, once hypothesized to represent a separate lineage and assigned to the genus Stylites, is here included in a phylogenetic study for the first time. It is closely related to some other South American species, despite its peculiar morphology with a dichotomizing stem. Conclusions. Despite limited intrageneric variation at the molecular and morphological levels, node ages as well as species composition (phylogeny) indicate a Mesozoic origin of the extant clade. Biogeographic patterns appear complicated and intriguing but need more research. Tuberculate megaspore ornamentation (sensu Pfeiffer) is ancestral in the genus, as indicated by current knowledge. Other megaspore patterns appear restricted to two subclades.
Subject headings
- NATURVETENSKAP -- Biologi (hsv//swe)
- NATURAL SCIENCES -- Biological Sciences (hsv//eng)
Keyword
- birth-death prior
- Gondwana
- Laurasia
- random local clock
- uncorrelated lognormal clock
- Yule prior
Publication and Content Type
- ref (subject category)
- art (subject category)
Find in a library
- International journal of plant sciences (Search for host publication in LIBRIS)
To the university's database
- 1 of 1
- Previous record
- Next record
- To hitlist
Find more in SwePub
- By the author/editor
- Larsén, Eva
- Rydin, Catarina
- About the subject
-
- NATURAL SCIENCES
- NATURAL SCIENCES
- and Biological Scien ...
- Articles in the publication
- International jo ...
- By the university
- Stockholm University
Search outside SwePub
- Extend your search to:
- Google Book Search
- Google Scholar
Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.
- Copyright © LIBRIS - National Library Systems
- LIBRIS.kb.se
