02184nam a2200205   4500008004100000245010800041210007100149260001200220300001400232490000700246520150100253653001701754653001501771653001201786653001401798100001501812700001701827700001701844856011701861       2006                        eng d00aPhylogeny and biogeography of Isoëtes (Isoëtaceae) based on nuclear and chloroplast DNA sequence data0 aPhylogeny and biogeography of Isoëtes Isoëtaceae based on nuclea  c2006///  a449 - 4600 v313 aDespite its ancient origins, worldwide distribution, and adaptation to diverse habitats, Isoëtes species have a highly conserved morphology, making it difficult to resolve phylogenetic relationships using morphological characters. In this paper, we report the results from various analyses (maximum parsimony, maximum likelihood, and Bayesian inference) for Isoëtes species from around the world based on nucleotide sequences from the nuclear internal transcribed spacer (ITS) and chloroplast atpB/rbcL intergenic spacer regions. The trees resulting from our analyses of the combined data contain six major well-supported clades (bootstrap ≥ 90%, posterior probabilities = 1.00): A clade with possible Gondwanan affinities (I. australis, I. coromandelina, I. panamensis, I. cubana, I. jamaicensis); a South African clade (I. capensis, I. toximontana, I. stellenbossiensis, I. stephansenii); a largely Northern Hemisphere clade (I. nuttallii, I. orcuttii, I. minima, I. dixitei, I. abyssinica, I. olympica, I. longissima, I. velata); an Asian/Australasian clade (I. drummondii, I. gunnii, I. pusilla, I. kirkii, I. muelleri, I. taiwanensis, I. japonica, I. yunguiensis, I. habbemensis); a Mediterranean clade (I. histrix and I. setacea); and a poorly resolved clade consisting of 12 new world species (American species complex). Our results are compared to past classifications and various biogeographical scenarios are explored. © Copyright 2006 by the American Society of Plant Taxonomists.10aBiogeography10aIsoetaceae10aIsoetes10aPhylogeny1 aHoot, S.B.1 aTaylor, W.C.1 aNapier, N.S.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-67650146436&partnerID=40&md5=c418d4b55db9dd7f2436a8d3189f155201966nas a2200217   4500008004100000245010000041210007000141260001200211300001400223490000700237520123800244653001501482653001201497653001401509653002101523653002201544653003001566100002001596700001501616856011701631       2006                        eng d00aInferring the root of Isoëtes: Exploring alternatives in the absence of an acceptable outgroup0 aInferring the root of Isoëtes Exploring alternatives in the abse  c2006///  a258 - 2700 v313 aThe ancient divergence between the lycopsid genus Isoëtes and its closest living relative (Selaginella) has resulted in considerable morphological and genetic disparity, yet within Isoëtes there is remarkable morphological and genetic uniformity. This has made it difficult to identify the phylogenetic root of the genus. In this study, we addressed this problem and characterized the early branching patterns within Isoëtes using an expanded set of taxa and three molecular markers. We assessed the saturation in the molecular data sets, tested for differences in evolutionary rate, determined the stability of the ingroup topology, and evaluated the applicability of the molecular clock. We then explored three alternative rooting approaches: outgroup, midpoint, and maximum likelihood under the assumption of a molecular clock. Attempts to infer the root of Isoëtes using the outgroup approach were severely hindered by the effects of saturation, but the results from midpoint rooting and the enforcement of the molecular clock were highly consistent among the data sets. We identify the root of Isoëtes to be located among three major, highly supported clades. © Copyright 2006 by the American Society of Plant Taxonomists.10aIsoetaceae10aIsoetes10aLycophyte10aMidpoint rooting10aPhylogenetic root10aRelative rate comparisons1 aSchuettpelz, E.1 aHoot, S.B.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-33745493624&partnerID=40&md5=8d3abb9eb77572545e97747f1aaf51a501157nas a2200205   4500008004100000245009000041210006900131260001200200300001400212490000800226520047700234653001100711653001500722653002800737653001600765653001700781100001800798700001800816856011700834       2006                        eng d00aIsoetes x novae-angliae (Isoetaceae), an additional hybrid quillwort from New England0 aIsoetes x novaeangliae Isoetaceae an additional hybrid quillwort  c2006///  a228 - 2410 v1083 aIsoetes x novae-angliae D.F. Brunt. & D.M. Britton, hyb. nov., represents a sterile hybrid between the tetraploid aquatic pteridophytes I. riparia and I. tuckermanii. It is known only from North Easton, Massachusetts although it formerly likely occurred across the state as well as in Connecticut and southern New Hampshire. Determination of the distribution and nomenclature of this taxon also clarifies the status of a number of early 20th century taxonomic innovations.10aHybrid10aIsoetaceae10aIsoetes x novae-angliae10aNew England10aPteridophyte1 aBrunton, D.F.1 aBritton, D.M.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-33750506895&partnerID=40&md5=cfb8fb103c449613c66501a4a452c5a6