01531nas a2200157   4500008004100000245008500041210006900126260001200195300001400207490000700221520097400228100001701202700001901219700001801238856011701256       2006                        eng d00aMicrospore morphology of Isoetes species (Lycophyta) from Southern South America0 aMicrospore morphology of Isoetes species Lycophyta from Southern  c2006///  a121 - 1340 v723 aMicrospores of the 24 species of Isoetes that grow in southern South America were analyzed under a light microscope and scanning electron microscope. The microspores are monolete, elliptic in polar view, 30-40 μm long, and 20-25 μm wide. A background with various characteristics is seen on each surface. A supra-laesural expansion is present. The perispore is ornamented and has a perforated background. In section, it has a lacunose structure. The exospore is smooth, and it has a compact structure in section. The studied species could be divided into three groups by their perispore ornamentation: equinate, rugulate, and tuberculate. Microspore size was positively correlated with increasing ploidy level, and larger microspores were associated with terrestrial habitats. A convergence in ornamentation was found between spores produced by the studied species and those that grow in regions outside of the area under study. © 2006 The New York Botanical Garden.1 aMacLuf, C.C.1 aMorbelli, M.A.1 aGiudice, G.E.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-33746007149&partnerID=40&md5=89828b318fcdc3d646eb9f235b2e34ee02147nas a2200157   4500008004100000245013100041210006900172260001200241300001400253490000700267520154400274100001701818700001901835700001801854856011701872       2006                        eng d00aMicrospore morphology of Isoetes species (Lycophyta) from Southern South America. Part II. TEM analysis of some selected types0 aMicrospore morphology of Isoetes species Lycophyta from Southern  c2006///  a135 - 1520 v723 aThe microspores of Isoetes escondidensis, I. gardneriana, I. herzogii, I. pedersenii, and I. savatieri were analyzed with transmission and scanning electron microscopy. The selected species were found to be representative of the diversity found in 24 taxa previously studied that grow in southern South America. The sporoderm is similar in the five types and is composed, from the outside to the inside, of perispore, para-exospore, exospore, and endospore. In I. escondidensis, I. gardneriana, I. herzogii, and I. savatieri, the perispore is lacunose, whereas in I. pedersenii, it is camerate. The para-exospore is formed of large superimposed and fused bars, which are more numerous and thicker in immature spores. The exospore shows uniform characteristics and a strongly contrasted cover. It has pluristratified zones on both sides of the aperture. The presence of radial rodlets between the para-exospore and exospore and in the supra-apertural chamber is described here for the first time. The endospore has a fibrillate or reticulate structure, or both structures may be present. A boundary within the fibrillate endospore is evident, which might be related to stages of deposition. The surface characteristics are formed by either the middle and outer strata of the perispore or elements on the outer surface, as in I. escondidensis. The characteristics of the microspore surface and of the perispore structure provide characteristics useful for systematic purposes at the infrageneric level. © 2006 The New York Botanical Garden.1 aMacLuf, C.C.1 aMorbelli, M.A.1 aGiudice, G.E.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-33746021654&partnerID=40&md5=26eb94864942b89e789f6d0eac8944dc00784nas a2200181   4500008004100000245006700041210006600108260001200174300001400186490000700200520019800207653001200405653001600417653001800433100001700451700001700468856011700485       2007                        eng d00aIsoetes araucaniana, a new species from southern South America0 aIsoetes araucaniana a new species from southern South America  c2007///  a220 - 2240 v973 aIsoetes araucaniana is newly described from central Chile. This aquatic species is endemic to Araucanía and is the only southern Andean species with strongly and densely reticulate megaspores.10aIsoetes10aNew species10aSouth America1 aMacLuf, C.C.1 aHickey, R.J.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-39449094567&partnerID=40&md5=187a92568719c2772ed711b49957998d00852nas a2200193   4500008004100000245004600041210004500087260001200132300001400144490000700158520027800165653001100443653001900454653001600473100001700489700001700506700001800523856011700541       2009                        eng d00aIsoetes maxima, a new species from Brazil0 aIsoetes maxima a new species from Brazil  c2009///  a194 - 1990 v993 aIsoetes maxima from eastern Brazil is described as a new species. This taxon differs from other fully aquatic species in South America by a combination of its overall size, leaf coloration, finely tapering subulae, and megaspore morphology. © 2009, Americian Fern Society.10aBrazil10aIsoetes maxima10aNew species1 aHickey, R.J.1 aMacLuf, C.C.1 aLink-Prez, M.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-76449121955&partnerID=40&md5=0bb4244c3bd0be9f7105bd2c1293d6fc