| Abstract Detail
Systematics/Phytogeography / Taxonomie/ Section Hansen, Debra R. [1], Jansen, Robert K. [1], Simpson, Beryl [1]. Phylogeny and biogeography of Pectis and Porophyllum (Asteraceae, Tageteae). Pectis is the largest and most widely-distributed genus in Tageteae. It comprises ±85 annual and perennial species, all found in deserts and the warmer regions of the New World. Pectis is most diverse in Mexico and the Caribbean, but species range from the southwestern U.S. to southern Brazil and northern Argentina, and two species are endemic to the Galapagos. Pectis species are morphologically distinct from other genera in the Tageteae and traditionally have been considered a monophyletic group. Previous molecular studies that included Pectis showed a close relationship between Pectis and Porophyllum (±30 sp), with the most recent study indicating some Porophyllum species are nested within Pectis. Here we present preliminary results of a phylogenetic study of Pectis and Porophyllum based on molecular data. We present analysis of nrDNA (ITS) sequences of 47 Pectis and 17 Porophyllum species. This analysis confirms that Pectis and Porophyllum are sister genera, but contrary to previous results, our data indicate that both Pectis and Porophyllum are monophyletic. At least two of the four Pectis sections and both Porophyllum sections are non-monophyletic. Our analysis shows that there have been multiple incursions of Pectis into the Caribbean, with subsequent, and probably rapid, radiation. Log in to add this item to your schedule
1 - University of Texas Austin, Section of Integrative Biology, 1 University Station, A6700, Austin, Texas, 78712-7640, USA
Keywords: Asteraceae Pectis phylogeny Porophyllum Tageteae.
Presentation Type: Oral Paper:Papers for Sections Session: 62 Location: 201/Law Date: Wednesday, July 30th, 2008 Time: 3:45 PM Number: 62011 Abstract ID:428 |