01660nas a2200109   4500008004100000245014900041210006900190490000700259520122600266100001401492856004401506       2016                        eng d00aDispersal and colonization in heterosporous lycophytes: palynological and biogeographical notes on the genus Isoetes in the Mediterranean region0 aDispersal and colonization in heterosporous lycophytes palynolog0 v553 aAfter a short review of the available information on dispersal in the heterosporous genus Isoetes, which has been the subject of some mainly anecdotal or occasional observations, a case study in the Mediterranean area is presented. In the geographical context given by the island of Sicily with its satellite islets and archipelagos, the distribution of terrestrial and amphibian Isoetes species was analysed to verify if any of them occurred in the oceanic (‘thalassogenous’) islets, never connected to the mainland. The only species revealed to be able to cross the geographical and ecological barrier represented by the sea and colonize some volcanic islands was Isoetes durieui Bory, a terrestrial polyploid species. On the basis of biological, ecological and morphological observations, including scanning electron microscope observations of the spores, the present work suggests that in this species – as in other terrestrial Isoetes species – animals could have a fundamental role in dispersal and dispersion, and synaptospory could be an important mechanism in dispersal events; in addition, polyploidy can be an important selective advantage for colonization events also in this group of vascular plants.1 aTroia, A.  uhttps://isoetes.myspecies.info/node/23401756nas a2200133   4500008004100000245007900041210006900120490000700189520132200196100002101518700002101539700001801560856004401578       2016                        eng d00aMegaspores of an early Miocene aquatic lycopod (Isoetales) from Antarctica0 aMegaspores of an early Miocene aquatic lycopod Isoetales from An0 v553 aThe paucity of late Paleogene and Neogene floras from Antarctica limits our ability to understand the interplay between Antarctic climate evolution and the impact that glaciation had on the vegetation, in particular, how the vegetation changed from temperate Eocene forests, to today’s sparse vegetation. Fluvial and lacustrine strata deposited in a wet-based glacial sequence (Friis Hills, McMurdo Dry Valley sector, Transantarctic Mountains) have yielded abundant megaspores. These strata are early Miocene based on correlation with a volcanic ash dated at 19.76 ± 0.11 Ma. The megaspores are up to 736 μm in diameter with well-developed wing-like laesurae and equatorial zona. The morphology is consistent with extant Isoetes, and demonstrates the presence of Lycopsida and the Isoetaceae within Antarctic Miocene floras. Today, Isoetes is widespread from the Tropics to the Arctic such as Greenland (I. echinospora, I. lacustris) and from marginal marine (I. ekmanii) to high altitudinal environments (I. lechleri), though commonly associated with lacustrine or aquatic environments. The fossil spores occur in fluvial and lacustrine beds, suggesting the parent plants were aquatics. The occurrence together with mosses and Nothofagus leaves points to persistent vegetation in the early Miocene of Antarctica.1 aCantrill, D., J.1 aAshworth, A., C.1 aLewis, A., R.  uhttps://isoetes.myspecies.info/node/23302267nas a2200133   4500008004100000245010200041210006900143300001200212490000700224520183300231100001302064700001202077856004402089       2016                        eng d00aComparative Transcriptome Analysis of Isoetes Sinensis Under Terrestrial and Submerged Conditions0 aComparative Transcriptome Analysis of Isoetes Sinensis Under Ter  a136-1450 v343 aIsoetes L. is an ancient genus of heterosporous lycopsids with a unique phylogenetic position. Repeated adaptations to environmental changes over time have contributed to occupying a variety of niches in Isoetes. However, we know little about how they adapt to the environmental changes, and the sequence resources are very limited in public databases. Isoetes sinensis is an amphibious plant in this genus, alternating frequently between terrestrial and aquatic environments. In this study, I. sinensis was applied to investigate the adaptations under terrestrial (TC) and submerged (ST) conditions using Illumina RNA-sequencing technology. Approximately 87 million high-quality reads were yielded and assembled into 31,619 unigenes with an average length of 1618 bp. Overall, 28,208 unigenes were annotated against the National Center of Biotechnology Information (NCBI), Non-redundant (Nr), Cluster of Orthologous Groups (COG), Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. Moreover, we identified 1740 differentially expressed genes with 1146 up-regulated and 594 down-regulated genes under TC. GO annotation revealed that stress-relevant categories were remarkably enriched, and KEGG enrichment analysis showed that the phytohormone signalings and carbohydrate metabolism were significantly influenced. Furthermore, a total of 1646 transcription factors (TF) were identified and classified into 54 TF families; among them, 180 TFs were dynamic between terrestrial and submerged conditions. This study is the first report for Isoetes to generate numerous sequences and establish general understandings about the adaptations in the changing environments. The dataset provides a foundation for novel gene discoveries, comparative genomics, functional genomics, and phylogenetics in Isoetes.1 aYang, T.1 aLiu, X.  uhttps://isoetes.myspecies.info/node/23102526nas a2200133   4500008004100000245008700041210006900128300001400197490000800211520210000219100001502319700001402334856004402348       2016                        eng d00aDisentangling the phylogeny of Isoetes (Isoetales), using nuclear and plastid data0 aDisentangling the phylogeny of Isoetes Isoetales using nuclear a  a157–1740 v1773 aPremise of research. The heterosporous lycopsids of Isoetes show limited morphological and genetic variation despite a worldwide distribution and the ancient origin of the lineage. Here major relationships within the genus are clarified, using a substantially larger sampling of species than in previous studies. A first assessment of divergence times of clades is made, and the implications for dispersal mechanisms and biogeographic distribution patterns are discussed. Methodology. On the basis of sequences from three gene regions and 109 specimens representing 74 species of Isoetes, phylogeny and node ages were estimated using parsimony and Bayesian inference. Pivotal results. Three rooting approaches (outgroup analysis, midpoint rooting, and clock rooting) coherently resolved a diverse clade containing species from South Africa, India, Australia, and South America (clade A) as sister to remaining Isoetes. Analysis of divergence times of clades yielded a median age of the crown group of 147 million years ago (mya) using a birth-death tree prior and 165 mya using a Yule tree prior. Clade A was dated to 111 or 125 mya, respectively. While the earliest divergences in Isoetes appear readily explained by ancient vicariance, patterns in younger clades are consistent with dispersal processes, sometimes over long distances. Isoetes andicola (Amstutz) L.D. Gómez, once hypothesized to represent a separate lineage and assigned to the genus Stylites, is here included in a phylogenetic study for the first time. It is closely related to some other South American species, despite its peculiar morphology with a dichotomizing stem. Conclusions. Despite limited intrageneric variation at the molecular and morphological levels, node ages as well as species composition (phylogeny) indicate a Mesozoic origin of the extant clade. Biogeographic patterns appear complicated and intriguing but need more research. Tuberculate megaspore ornamentation (sensu Pfeiffer) is ancestral in the genus, as indicated by current knowledge. Other megaspore patterns appear restricted to two subclades.1 aLarsen, E.1 aRydin, C.  uhttps://isoetes.myspecies.info/node/23002040nas a2200133   4500008004100000245007500041210007000116300001000186490000800196520162400204100001601828700001801844856004401862       2016                        eng d00aGeographic scales of genetic variation amongst Isoëtes in New Zealand0 aGeographic scales of genetic variation amongst Isoëtes in New Ze  a28-370 v1313 aEndemic plants of the genus Isoëtes occur as obligate submerged species in freshwater lakes and slow-flowing waterways in New Zealand. Some populations of are under threat or extinct following habitatdeterioration. Genetic techniques have been employed to clarify population variation along geographicscales and to focus conservation efforts on unique, or representative populations. plants were sampledfrom a wide geographic range including lakes on both the North and South Island, with a finer spatialscale (sites and depths within lakes) investigated for four larger lakes within which a larger numberof plants could be collected. RAPD (random amplified polymorphic DNA) profiles generated from eightprimers were determined for 254 plants from 20 lakes. The majority of the diversity was partitionedbetween (81%) rather than within populations (19%). Lakes were separated into four clusters (UPGMA),two clusters included only South Island lakes, one comprised a single North Island lake and the fourthcluster included lakes from a wide geographic range. There was a weak correlation between geographicand genetic distance indicating that factors other than isolation by distance determine variation betweenthe populations. As there is a high percentage of genetic variation between populations, the extinctionof any population would substantially reduce the total genetic variability for the species. In this contextthe recognition of the genetically distinct populations of Isoëtes and clustering of lakes has significantimplications for their contribution to the conservation of New Zealand Isoëtes as a whole.1 aHofstra, D.1 ade Winton, M.  uhttps://isoetes.myspecies.info/node/229