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St. Louis, MO, United States

Bedigian D.,Missouri Botanical Garden
Genetic Resources and Crop Evolution

Descriptor characterization of sesame accessions regenerated in Georgia, USA gave only a very limited picture of the wealth of sesame diversity, and an inaccurate portrayal of literature pertaining to the crop's domestication. Background information is far richer than touched upon in Morris's paper, as elaborated in this appraisal. Patterns of sesame's genotypic diversity follow geographic lines. Data from parallel approaches: taxonomic, genetic and molecular, identify the wild progenitor of sesame from the taxon Sesamum orientale var. malabaricum Nar. © 2010 Springer Science+Business Media B.V. Source

Aims: I determine the relative importance of temperature and moisture acting alone and in tandem for range contractions and expansions of mammalian species over c. 70 years. Location: The contiguous United States west of the eastern border of the Rocky Mountains (103.77°W). Methods: Museum records of 67 mammalian species from two time periods (1900-39 and 1970-2009), mean annual temperature and mean annual precipitation are used to model historic and modern distributions. For each era the region outside each species' range in the opposing era is assigned to zones of range limitation: temperature alone is prohibitive, moisture alone is prohibitive, both preclude the species, or both have values that alone are within the species' tolerance range but in combination are outside its climatic niche ('interaction' limitation). The relative importance of each type of limitation is estimated by their intersection with regions of range contraction and expansion. Results: Averaged across species, 82±3% (±SE) of the areas of contraction are now occupied by interaction limitation, and 74±5% of areas expanded into were historically occupied by similar zones. In comparison, areas of range shift in which just temperature or moisture acting alone would have excluded the species comprise between only 9 and 17%, and areas in which both factors are limiting are negligible. Expansions into and contractions from regions of interaction limitation occurred more often than expected by chance given the distribution of this type of limitation in the wider study region. Main conclusions: Particular combinations of temperature and moisture can interact directly or indirectly to limit species ranges even when these factors alone do not exceed species tolerances. Change in the correlation between of range-limiting factors can have as much effect on species ranges as absolute change in those factors by themselves. © 2012 Blackwell Publishing Ltd. Source

Applequist W.L.,Missouri Botanical Garden

The following eight generic names are recommended for conservation: Brasiliorchis against Bolbidium, Codariocalyx with that spelling, Dehaasia with that spelling, Lepisorus against three generic names (Belvisia, Drymotaenium, Paragramma) but not against Lemmaphyllum and Neocheiropteris, Meiogyne against Fitzalania, Physalis with conserved type, Sobralia with conserved type and Stichorkis with conserved type. The following two generic names are not recommended for conservation: Enicosanthum against Monoon and Isidrogalvia with conserved type. Conservation of Trigonotis against Endogonia was considered to be unnecessary because the Committee recommends that the latter be treated as a homonym of Endogona (see below). The following 14 species names are recommended for conservation: Acrostichum ebeneum with conserved type, Alyssum montanum with conserved type, Amomum villosum with conserved type, Croton arboreus Millsp. against C. arboreus Shecut, Hibiscus simplex with conserved type, Mespilus tomentosa against M. orientalis, Morinda citrifolia with conserved type, Onychium japonicum (Thunb.) Kunze against O. japonicum Blume, Pandanus pervilleanus against P. boucheanus, Pteris arachnoidea against Aspidium brasilianum and P. psittacina, Solidago doronicum with conserved type as amended, Spermacoce capitata Ruiz & Pav. against S. capitata P.J. Bergius, Viola elatior against V. hornemanniana and V. stipulacea, and Zamia integrifolia with conserved type. The following 10 species names are not recommended for conservation: Acalypha alnifolia J.G. Klein ex Willd. against A. alnifolia Poir. and A. capitata, Blechnum hawaiianum against B. norfolkense, Euphrasia kaliformis with conserved type, Filago vulgaris against Gnaphalium germanicum, Gymnadenia rubra against Orchis miniata, Lockhartia oerstedii against Oncidium mirabile, Oreochloa blanka against O. elegans, Senecio gerardi against Inula provincialis, Senecio paucifolius with conserved type, and Viscum serotinum against V. leucarpum. The following 10 species names are recommended for rejection: Corispermum orientale, Croton citrifolius, Heptallon simplex, Maxillaria ramosa, Oncidium mirabile, Solanum ferox, Solanum fuscatum, Sophora lupinoides, Viola montana, and Viola persicifolia. One species name, Echinocactus acanthodes, is not recommended for rejection. It is recommended that with respect to names of genera and species E. Delpy's entire series of illustrations of West African trees be added to the list of suppressed works in Appendix VI. It is recommended that Echinodorus Richard, Podocarpus cunninghamii Colenso, and Primula thearosa Kingdon-Ward be treated as validly published, and that Toulicia eriocarpa Radlk. be treated as not validly published. As noted above, it is recommended that Endogonia (Turcz.) Lindl. and Endogona Raf. be treated as homonyms. After two ballots, no vote of at least 11 either for or against a proposal to superconserve Melianthaceae against Francoaceae has been obtained. Source

Al-Shehbaz I.A.,Missouri Botanical Garden

As currently delimited, the Brassicaceae comprise 49 tribes, 321 genera, and 3660 species. Of these, 20 genera and 34 species remain to be assigned to tribes. These figures differ substantially from those estimated five years ago, in which 25 tribes, 338 genera, and 3709 species were recognized. Of those 338 genera, 37 are treated herein as synonyms, and 21 genera (10 re-established and 11 new) have since been added. The genera Notothlaspi, Peltariopsis, Sinapidendron, and Xerodraba are lectotypified. The following 11 taxa are reduced for the first time to synonymy of what follows them in parentheses: Boreava and Tauscheria (Isatis), Catadysia (Weberbauera), Coelophragmus (Dryopetalon), Crambeae (Brassiceae), Eremodraba (Neuontobotrys), Leavenworthieae (Cardamineae), Lexarzanthe (Romanschulzia), Noccaeopsis (Noccaea), Romanschulzia orizabae (R. arabiformis), and Sibaropsis (Streptanthus). The new names Isatis zarrei and I. quadrialata are proposed to avoid the creation of later homonyms upon the transfers to Isatis of the herein lectotypified Boreava orientalis and Sameraria nummularia, respectively. Twenty-seven new combinations are proposed: Abdra aprica, Camelinopsis kurdica, Dryopetalon auriculatum, Isatis aptera, I. cardiocarpa, I. glastifolia, I. gymnocarpa, Neuontobotrys intricatissima, N. schulzii, Noccaea apterocarpa, N. caespitosa, N. iberidea, N. oppositifolia, Onuris hauthalii, Parlatoria taurica, Petroravenia friesii, P. werdermannii, Streptanthus barnebyi, S. cooperi, S. hammittii, Tomostima araboides, T. australis, T. cuneifolia, T. platycarpa, T. reptans, T. sonorae, and Weberbauera rosulans. Source

Modelling the distribution of rare and invasive species often occurs in situations where reliable absences for evaluating model performance are unavailable. However, predictions at randomly located sites, or 'background' sites, can stand in for true absences. The maximum value of the area under the receiver operator characteristic curve, AUC, calculated with background sites is believed to be 1 - a/2, where a is the typically unknown prevalence of the species on the landscape. Using a simple example of a species' range, I show how AUC can achieve values > 1 - a/2 when test presences do not represent each inhabited region of a species__ range in proportion to its area. Values of AUC that surpass 1 - a/2 are associated with higher model predictions in areas overrepresented in the test data set, even if they are less environmentally suitable than other regions the species occupies. Pursuit of high AUC values can encourage inclusion of spurious predictors in the final model if they help to differentiate areas with disproportionate representation in the test data. Choices made during modelling to increase AUC calculated with background sites on the assumption that higher scores connote more accurate models can decrease actual accuracy when test presences disproportionately represent inhabited areas. © 2013 John Wiley & Sons Ltd. Source

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