01207nas a2200193   4500008004100000245012200041210006900163260001200232300001400244490000700258520051300265653002600778653001500804653002500819653001700844100001800861700001800879856011600897       1997                        eng d00aAppalachian quillwort (Isoetes appalachiana, sp. nov.; Isoetaceae), a new pteridophyte from the eastern United States0 aAppalachian quillwort Isoetes appalachiana sp nov Isoetaceae a n  c1997///  a118 - 1330 v993 aIsoetes appalachiana, sp. nov., is an element of the I. engelmannii complex of North America. Its distinct cytology, spore morphology, and distribution are illustrated and described. Although widely distributed in the eastern United States, it appears to be most common in the Appalachian Mountains. Isoetes appalachiana is tetraploid; it is suspected to be an allopolyploid which evolved from the chromosome doubling of I. X altonharvillii, the sterile hybrid between I. engelmannii (s. str.) and I. valida.10aAppalachian Mountains10aIsoetaceae10aIsoetes appalachiana10aPteridophyte1 aBrunton, D.F.1 aBritton, D.M.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-0013681071&partnerID=40&md5=ca09a6b7a394918dfcfa73009b9ad85b01453nas a2200217   4500008004100000245010000041210006900141260001200210300001400222490000700236520073900243653001500982653001200997653001201009653002901021653001701050100001601067700001701083700001801100856011701118       2005                        eng d00aAnalysis of morphological and anatomical characteristics of Isoetes using isoetes tennesseensis0 aAnalysis of morphological and anatomical characteristics of Isoe  c2005///  a167 - 1820 v573 aThe three known populations of Isoetes tennesseensis were examined to document and analyze their morphological and anatomical characters. Characters examined included velum coverage, lacunae, leaf form and size, sporangial wall cells, and ligule and labium morphology. Three types of morphological patterns were found: stable, variable, and dimorphic. The discovery of dimorphism between mega- and microsporophylls for velum coverage, velum length, sporangium size, and ligule shape is of particular interest. This study presents a model for future work designed to complement current species descriptions and it establishes a baseline for morphological comparisons with other Isoetes. © 2005, by The New York Botanical Garden Press.10aDimorphism10aIsoetes10aLycopod10aMorphological characters10aPteridophyte1 aBudke, J.M.1 aHickey, R.J.1 aHeafner, K.D.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-21744447722&partnerID=40&md5=10d5e4181461bf404f341ea4a32c474003003nas a2200229   4500008004100000245011300041210006900154260001200223300001600235490000700251520223800258653000902496653002802505653002202533653002102555653002502576653001702601100001302618700001102631700001402642856011702656       2005                        eng d00aGenetic consequence of restricted habitat and population decline in endangered Isoetes sinensis (Isoetaceae)0 aGenetic consequence of restricted habitat and population decline  c2005///  a1265 - 12740 v963 a• Background and Aims: Isoetes sinensis (Isoeteaceae) is a critically endangered aquatic quillwort in eastern China. Rapid decline of extant population size and local population extinction have occurred in recent years and have raised great concerns among conservationists. • Methods: Amplified fragment length polymorphisms (AFLPs) were used to investigate the genetic variation and population structure of seven extant populations of the species. • Key Results: Eight primer combinations produced a total of 343 unambiguous bands of which 210 (61·2 %) were polymorphic. Isoetes sinensis exhibited a high level of intra-population genetic diversity (H E) = 0·118; hs = 0·147; I = 0·192; P = 35·2 %). The genetic variation within each of the populations was not positively correlated with their size, suggesting recent population decline, which is well in accordance with field data of demographic surveys. Moreover, a high degree of genetic differentiation (FST = 0·535; G ST = 0·608; θB = 0·607) was detected among populations and no correlation was found between geographical and genetic distance, suggesting that populations were in disequilibrium of migration-drift. Genetic drift played a more important role than gene flow in the current population genetic structure of I. sinensis because migration of I. sinensis is predominantly water-mediated and habitat range was highly influenced by environment changes. • Conclusions: Genetic information obtained in the present study provides useful baseline data for formulating conservation strategies. Conservation management, including both reinforcement for in situ populations and ex situ conservation programmes should be carefully designed to avoid the potential risk of outbreeding depression by admixture of individuals from different regions. However, translocation within the same regional population should be considered as a measure of genetic enhancement to rehabilitate local populations. An ex situ conservation strategy for conserving all extant populations to maximize genomic representation of the species is also recommended. © The Author 2005. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved.10aAFLP10aGenetic differentiation10aGenetic diversity10aIsoetes sinensis10aPopulation structure10aPteridophyte1 aKang, M.1 aYe, Q.1 aHuang, H.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-27944462292&partnerID=40&md5=26404edf2320e666820f93f6dd369ebf