Colloquium in Honor of John McNeill
Harbaugh, Danica T. , Wagner, Warren , Nepokroeff, Molly , Rabeler, Richard , McNeill, John , Zimmer, Elizabeth .
Extensive polyphyly in the Caryophyllaceae leads to new classification.
Understanding the relationships within the Caryophyllaceae is difficult, in part because of difficulty in determining phylogenetically useful morphological characters. In our 2010 study, we sampled broadly across the family, with a particular focus on the large subfamily Alsinoideae. Sampling was partially designed to resolve the obscure origins of the divergent endemic Hawaiian genus Schiedea. Our emphasis on Alsinoideae was coincidently very similar to the focus of a careful morphological study by John McNeill in 1962, which formed the basis for much of the sampling we used. Chloroplast data (matK, trnL-F, and rps16) were generated or obtained from GenBank for 126 species representing 46 of 80-85 genera in the family. Our analyses showed that each of the three subfamilies as traditionally defined, as well as several tribes and genera, especially within the Alsinoideae, are not monophyletic, suggesting that a classification based on tribes is more appropriate. Subfamily Paronychioideae forms a basal paraphyletic grade of four clades (each a tribe); Corrigioleae, Paronychieae (Paronychia, Gymnocarpos, Herniaria; excluding Dicheranthus, which is nested within tribe Polycarpaeae), Polycarpaeae (Polycarpon, Ortegia, Loeflingia, Drymaria), and Sperguleae (Spergula, Spergularia). The traditional subfamily Caryophylloideae is polyphyletic with two separate clades: a) tribe Drypidae placed in a clade with several Alsinoideae genera; and b) remaining genera, expressed as tribes Sileneae and Caryophylleae. Subfamily Alsinoideae is also polyphyletic. The Andean genus Pycnophyllum is nested within the Polycarpaeae, sister to Drymaria. Minuartia subg. Rhodalsine is associated with Spergularia and Spergula in the Sperguleae, while parts of Arenaria (subg. Eremogone, Eremogoneastrum) and Minuartia (subg. Spergella) form a clade, the tribe Eremogoneae, that would belong in subfam. Caryophylloideae. Large genera including Arenaria (>210 species) and Minuartia (175 species) are polyphyletic and appear in multiple clades within the Alsinoideae, and likely require significant taxonomic changes to delimit monophyletic generic boundaries. Two groups of Minuartia (subg. Hymenella, part of subg. Minuartia) are in a clade of tribe Sclerantheae with divergent genera like Scleranthus, Schiedea, Geocarpon, and Honckenya, while another forma a clade with Sagina and Colobanthus in tribe Sagineae. Arenaria subg. Odonostemma is included in a clade with Pseudostellaria and Lepyrodiclis, as well as the enigmatic Arenaria chamissonis. Members of Arenaria subg. Arenaria, Leiosperma, and Porphyrantha, as well as all members of the genus Moehringia, form another clade (tribe Arenarieae). Several other recent studies support and in some cases extend the results of our work.
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1 - AuthenTechnologies LLC, 405 Kains Ave Suite 203, Albany, CA, 94706, USA
2 - Smithsonian Institution, Botany, MRC-166 National Museum Of Natural History, PO Box 37012, WASHINGTON, DC, 20013-7012, USA, 202/633-0968
3 - University Of South Dakota, Department Of Biology, 414 E CLARK ST, VERMILLION, SD, 57069-2390, USA
4 - The University of Michigan, Herbarium, 3600 Varsity Dr., Ann Arbor, MI, 48108-2228, USA
5 - Royal Ontario Museum and Royal Botanic Garden, EH3 5LR, Edinburgh , Scotland, UK
6 - Smithsonian Museum Support Center, MUSEUM SUPPORT CENTER, 4210 Silver Hill Rd., Suitland, MD, 20746, USA
Presentation Type: Symposium or Colloquium Presentation
Location: Delaware D/Hyatt
Date: Monday, July 9th, 2012
Time: 4:00 PM