00905nas a2200217   4500008004100000245007900041210006900120260001200189300001400201490000700215520020800222653001700430653001700447653002000464653002100484653001400505100001700519700001600536700001900552856011600571       2001                        eng d00aThe genus Isoetes (Isoetaceae: Pteridophyta) in Mallorca, Balearic Islands0 agenus Isoetes Isoetaceae Pteridophyta in Mallorca Balearic Islan  c2001///  a205 - 2080 v163 aThe distribution and previously confused recording history of the genus Isoetes on Mallorca, Balearic Islands, is documented and clarified. Two species, I. duriei and I. histrix are confirmed as present.10aConservation10aDistribution10aIsoëtes duriei10aIsoëtes histrix10aQuillwort1 aRumsey, F.J.1 aVogel, J.C.1 aStafford, P.J.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-0039740289&partnerID=40&md5=86b1fbc1ac46b33dff89643989686e2102366nas a2200145   4500008004100000245016300041210006900204260001200273300001400285490000700299520176600306100001502072700001702087856011602104       2001                        eng d00aThe utility of nuclear ITS, a LEAFY homolog intron, and chloroplast atpB-rbcL spacer region data in phylogenetic analyses and species delimitation in Isoëtes0 autility of nuclear ITS a LEAFY homolog intron and chloroplast at  c2001///  a166 - 1770 v913 aDespite its ancient origins, its worldwide distribution, and adaptation to diverse habitats, Isoëtes has a highly conserved morphology. This feature has made it difficult to resolve species and species relationships using morphological characters. In this paper, we report the utility of nucleotide sequences from the nuclear internal transcribed spacer (ITS) regions, chloroplast atpB/rbcL intergenic spacer region, and second intron of a LEAFY (LFY) homolog for identifying species relationships, delimiting basic diploid species, and determining hybrid origins. Variation in the ITS regions and atpB/rbcL spacer is most useful at the family level in Isoëtes and the LFY second intron is appropriate at the species and population level. The tree resulting from an analysis of the combined nuclear ITS and chloroplast atpB/rbcL spacer contains three major well supported clades (bootstrap ≥ 99%): an Old-World/California clade (I. abyssinica, I. longissima, I. velata, I. nuttallii, and I. orcuttii), an Asian/Australian clade (I. taiwanensis, I. japonica, I. kirkii, and I. drummondii), and a poorly resolved clade consisting of nine North American species. To further resolve and delimit the North American species, a combination of the LEAFY second intron and ITS data was used. The resulting consensus tree has limited resolution, supporting the hypothesis that the North American species complex radiated rapidly. The combination of LFY and ITS data provided numerous characters, both substitutions and indels, that are useful in species delimitation and identification of cryptic species. ITS sequence data, through additive banding and sequence misalignment, is also useful in confirming interspecific hybrids and determining their parental origins.1 aHoot, S.B.1 aTaylor, W.C.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-0040332183&partnerID=40&md5=e97f5c223e9a884b67c6347a0db81dd501753nas a2200145   4500008004100000245006600041210006600107260001200173300001200185490000700197520125400204100001601458700001701474856011601491       2001                        eng d00aSystematics of the Northern Andean Isoëtes karstenii complex0 aSystematics of the Northern Andean Isoëtes karstenii complex  c2001///  a41 - 690 v913 aThe Isoëtes karstenii complex includes those species characterized by laevigate megaspores, acute to free ala apices, a highly reduced labium, and distributions in the high altitude páramos of Venezuela, Colombia, and Ecuador. These species have been variously treated in the literature. Many early authors placed all Andean laevigate-spored specimens in Isoëtes lechleri, a central Andean species, while one later author recognized up to eight northern Andean species distinct from I. lechleri. This research represents a revisionary study to determine the number and identity of the taxa in this complex. Multivariate and descriptive analyses of morphological data and chromosome counts were performed. Five species are recognized including the previously described I. karstenii and I. palmeri. One variety is transferred from I. lechleri to I. karstenii (I. karstenii var. anomala). Three of the recognized species are newly described: I. fuliginosa, I. hemivelata and I. precocia. Chromosome counts revealed that I. karstenii and I. precocia are diploids (2n = 22) and that I. palmeri is tetraploid (2n = 44). Estimates of chromosome number based on spore size for I. fuliginosa and I. hemivelata indicate that they are polyploid (2n ≥ 44).1 aSmall, R.L.1 aHickey, R.J.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-0038976036&partnerID=40&md5=b6f84ea9232d1f6136401b0eed96557701128nas a2200229   4500008004100000245010400041210006900145260001200214300001400226490000700240520039300247653001500640653001200655653001800667653001400685653001800699653001300717100002000730700001700750700001500767856011600782       2001                        eng d00aIsoetes mattaponica (Isoetaceae), a new diploid quillwort from freshwater tidal marshes of Virginia0 aIsoetes mattaponica Isoetaceae a new diploid quillwort from fres  c2001///  a200 - 2040 v113 aIsoetes mattaponica is a rare quillwort of freshwater tidal rivers of eastern Virginia with a somatic chromosome number of 2n = 22. Megaspores have low regulate muri on both the proximal and distal surfaces; the girdle is broad. Microspores are echinate-spinose with ornamented spines. Isoetes mattaponica may be one of the parents of several polyploids in the Southeastern United States.10aIsoetaceae10aIsoetes10aNorth America10aQuillwort10aUnited States10aVirginia1 aMusselman, L.J.1 aTaylor, W.C.1 aBray, R.D.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-0034905622&partnerID=40&md5=0a918d8dca0158c2b1216f1b1f080cd002233nas a2200241   4500008004100000245008100041210006900122260001200191300001600203490000800219520151000227653001201737653001601749653001201765653001901777653001301796653001501809653001501824653000901839100001401848700001301862856011601875       2001                        eng d00aBasal meristem and root development in Isoetes asiatica and Isoetes japonica0 aBasal meristem and root development in Isoetes asiatica and Isoe  c2001///  a1225 - 12350 v1623 aWe studied the anatomy of the basal meristem and root development in Isoetes asiatica and Isoetes japonica to better understand the Isoetes rhizomorph, an enigmatic organ. The basal (root-producing) meristem of the rhizomorph is continuous with the lateral meristem, and both comprise a single meristem. The basal meristem with a layer of thin initials has both organogenetic and thickening meristem attributes. A combination of these attributes indicates that the basal meristem is distinctive among the vascular plant meristems, including cambium. The root primordia develop from young derivative cells organized in three to four radial fines, and their main body is composed of a three-layered apical meristem. The primordia, unlike the roots, produce a small number of derivative cells as well as a procambium and future root cap, and they do not form a cortex and epidermis. Prior to developing into roots, the primordia are shifted closer to the corm surface through further development of cortical tissues from the basal meristem and sloughing of surface cells. This unique developmental pattern is established through the subendogenous origin of the second embryonic root and the endogenous origin of the third root. The meristem and pattern of root development in Isoetes is compared with that indicated for the lepidodendrid and isoetalean rhizomorphs and contrasted with that in the Selaginella rhizophore. The comparison seems not to support the interpretation of the roots as leaf homologues.10aCambium10aDevelopment10aIsoetes10aLepidodendrids10aMeristem10aRhizomorph10aRhizophore10aRoot1 aYi, S.-Y.1 aKato, M.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-0034749638&partnerID=40&md5=1887916a18c476c09780d6d6ad7f78b600789nas a2200181   4500008004100000245004500041210004300086260001200129300001200141490000700153520025300160653002000413653001000433653001300443100001700456700001800473856011600491       2001                        eng d00aMorphology of labium/velum in Isoetes L.0 aMorphology of labiumvelum in Isoetes L  c2001///  a57 - 610 v513 aComparison is made between the unique structure labium/velum of Isoetes and the indusium of ferns. All three structures are derived from a common ancestor. The hypothesis is based on the study of labium and velum in three Indian species of Isoetes.10aCommon ancestor10aFerns10aLycopods1 aSharma, B.D.1 aPurohit, S.N.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-0035240804&partnerID=40&md5=ac0eecd2b088c84348c60a89a9cc193900356nas a2200097   4500008004100000245008100041210006900122490000700191100001800198856004200216       2001                        eng d00aThe genus Isoetes L. (Lycophyta, Isoetaceae): synthesis of karyological data0 agenus Isoetes L Lycophyta Isoetaceae synthesis of karyological d0 v561 aTroia, Angelo  uhttps://isoetes.myspecies.info/node/1