Stipa valdemonensis (Poaceae), a new species from Sicily

Abstract

A new species of Stipa, endemic to Sicily, named Stipa valdemonensis is described here. The new taxon is related to Stipa crassiculmis. Owing to the small number of individuals observed, in few restricted localities only, it is assigned the IUCN threat status “vulnerable”.     

Disteganthus lateralis (Bromeliaceae), a new combination for the flora of central French Guiana

The new combination,Disteganthus lateralis, is coined based onAechmea lateralis. An illustration for this species is provided.     

Morphological variation and taxonomy of thePoa macrocalyx complex (Poaceae) in Hokkaido

Morphological features of 41 local populations of thePoa macrocalyx complex from the seasides of Hokkaido were analyzed with special reference to the following seven characters: spikelet length, number of florets per spikelet, relative length of side nerves to the entire length of the first glume, that of the second glume, length ratio of the second glume to a spikelet, ratio of length of the closed part vs. entire length of leaf sheaths, and scabrousness of panicle branches and pedicels. All of these characters varied continuously, and considerable degrees of variability within a population were observed. However, separation of populations into three groups became evident when the data were subjected to principal component analysis and also to a method of examination which was devised for identification of a population (not an individual) of this complex. The three groups that resulted from morphological studies were exactly in parallel with the grouping of populations supported by differences of chromosome numbers and geographical distribution. Evolutionary differentiation of this complex was discussed in connection with polyploidy and gametophytic apomixis. As a result of taxonomic considerations, the plants were arranged in three emended varieties of one species:Poa macrocalyx var.fallax, P. m. var.tatewakiana, P.m. var.scabriflora.     

Stipa zeravshanica sp. nov. (Poaceae), an endemic species from rocky walls of the western Pamir Alai Mountains (middle Asia)

Stipa zeravshanica M. Nobis sp. nov. from the western Pamir Alai Mts (Tajikistan) is described and illustrated. Morphologically, the new species is similar to S. gracilis, but it is easily distinguishable by pilose (vs. glabrous) lower part of the awn, and generally somewhat longer ligules of the vegetative shoots. Epidermal patterns of the lemma in S. zeravshanica and three other closely related taxa, namely S. gracilis, S. himalaica and S. orientalis, were examined by means of SEM. The main macro‐morphological and micro‐morphological characteristics differentiating all mentioned species are presented. Additionally, a lectotype for S. gracilis is designated. Based on phytosociological relevés prepared during field investigation in the western Pamir Alai Mts, a new plant association Asperulo albiflorae–Stipetum zeravshanicae, occurring on shelves and rocky crevices is also described.     

Remarks on the Taxonomy and nomenclature of theCarex bigelowii complex

Carex bigelowii complex is a group of taxa distributed over the whole Arctic region and in the mountains of the temperate zone. The species was described from the White Mountains in the eastern part of USA. The plants from Central Europe, the British Isles and Fennoscandinavian mountains differ from the plants of the typelocality in a number of characters, especially in the character of the inflorescence. On the basis of these differences the European plants represent a new taxon which is described asCarex bigelowii Torr. exSchweinitz subsp.nardeticola Holub, subsp. nova. Very closely related plants to the new taxon are known from Central Siberia and from the Arctic region.     

Variation and taxonomy in Hordeum depressum and in the H. brachyantherum complex (Poaceae)

The variation pattern in the perennial Hordeum brachyantherum complex and in the annual H. depressum are described. The diploid form of H. brachyantherum s. lat., endemic to California in USA, previously recognized as a separate species is here treated as a subspecies ( H. brachyantherum ssp. californicum ). Despite its restricted distribution it shows a considerable variation and overlap in morphology with the tetraploid ssp. brachyantherum , and no unambiguous determination based on morphology between the two tax a is possible. The tetraploid cytotype has a large distribution area in western North America and easternmost Asia and a very wide morphological variation. It has also a small disjunct distribution area in easternmost Canada. A single hexaploid population from California is referred to ssp. brachyantherum .     

Maranthes (Chrysobalanaceae), a new generic record for America

Maranthes, a genus well known in Africa and Asia, has not been recorded previously in the New World.Couepia panamensis, thought to be endemic to Panama, was found to be synonymous withMaranthes corymbosa, a widespread Asiatic species, and it is reduced into synonymy, making the first American record ofMaranthes. The relationship ofMaranthes toCouepia, and the unusual distribution ofM. corymbosa are discussed.     

The family Schisandraceae: a new record for the flora of Mexico

A population ofSchisandra glabra (Schisandraceae) found in the cloud forest of northeastern Hidaglo state, Mexico, represents a new family for the Mexican flora and the first record for the species outside of the southeastern United States. Morphological comparisons of foliar and floral characteristics of this population with southeastern U.S. specimens reveal the material in both countries to be similar in morphology and apparently conspecific.Schisandra glabra is the only species of the family on the American continent. We speculate that the disjunct distribution of the Mexican population is the result of the gradual contraction of an otherwise wider distribution in connection with climatological changes associated with the Tertiary. The species is described and illustrated to familiarize students interested in the Mexican flora with the species and family.     

Communities of arbuscular mycorrhizal fungi in Stipa krylovii (Poaceae) in the Mongolian steppe

We examined arbuscular mycorrhizal (AM) fungi colonizing the roots of Stipa krylovii, a grass species dominating the grasslands of the steppe zone in Hustai and Uvurkhangai in Mongolia. The AM fungal communities of the collected S. krylovii roots were examined by molecular analysis based on the partial sequences of a small subunit of ribosomal RNA gene as well as AM fungal colonization rates. Almost all AM fungi detected were in Glomus-group A, and were divided into 10 phylotypes. Among them, one phylotype forming a clade with G. intraradices and G. irregulare was the most dominant. Furthermore, it was also found that most of the phylotypes include AM fungi previously detected in high altitude regions in the Eurasian Continent. Significant correlations were found among soil total N, total plant biomass and AM fungal colonization ratio, which suggested that higher plant biomass may be required for the proliferation of AM fungi in the environment. Meanwhile, redundancy analysis on AM fungal distribution and environmental variables suggested that the effect of plant biomass and most soil chemical properties on the AM fungal communities were not significant.     

Andropogon crispifolius (Poaceae: Andropogoneae): a new species from the cerrado of central Brazil

Andropogon crispifolius a new species from the environs of the Parque Nacional das Emas (in the states of Goiás and Mato Grosso do Sul) in central Brazil is here described, illustrated and compared with A. pohlianus Hack. It is a large, perennial, coarse grass characterized primarily by its strongly crispate older leaves. This new species is placed in sect. Notosolen Stapf, previously represented in South America by a single species, A. pohlianus .