ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1992.tb00276.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

SAUNDERS, R. M. K.&FOWLER, K., 1992.A morphological taxonomic revision ofAzollaLam. sectionRhizosperma(Mey.) Mett. (Azollaceae). Recent research on the agronomically important aquatic fernAzollahas been hampered by the lack of a sound taxonomic framework. The classification of sectionRhizospermais revised using multivariate statistical analyses of ultrastructural, gross morphological and anatomical characters. The disparate morphologies and current delimitations ofA. pinnataandA. niloticaare corroborated. Three distinct geographically related subspecies ofA. pinnataare identified and formally named and described as: 1. subsp.pinnata, occurring in northern and eastern Australia and New Caledonia; 2. subsp.asiaticasubsp. nov., occurring in India, southern China, south‐east Asia and southern Japan; and 3. subsp.africanastat. et comb, nov., occurring in tropical Africa and Madagascar. A sequential dichotomous key is provided for the identification of taxa, with new taxonomic description

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1992.tb00277.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

BUENO SANCHEZ, A., FERNANDEZ CASADO, M. A., FERNANDEZ PRIETO, J. A., 1992.A new subspecies ofRanunculus parnassiifoliusL. (Ranunculaceae) from the Cantabrian Mountains, Spain. Specimensof Ranunculus parnassiifoliusnot easily matched with any of the known subspecies were collected in the Western Cantabrian Mountains (Biological Reserve of Muniellos). A comparison of the known subspecies of the taxon and the Muniellos specimens led to the description of a new taxon,R. parnassiifoliussubsp.muniellensis.

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1992.tb00278.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

CRESPO, MB., 1992.A new species ofVellaL. (Brassicaceae) from the south‐eastern part of the Iberian Peninsula.Vella lucenlinais described from the coastal, low, dry areas of Alicante Province (south‐eastern Spain). This plant is a spineless shrub, woody at the base, with narrowly linear, entire leaves, and an acute tongue‐shaped stylar part of the fruit. Affinities and differences with the other taxa in the genus are discussed, and ecological data and conservation proposals are rep

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1992.tb00279.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

HEDBERG, K. O., 1992.Taxonomic differentiation inSaxifraga hirculusL. (Saxifragaceae)–a circumpolar Arctic‐Boreal species of Central Asiatic origin. Field fixations of specimens from Arctic Canada yielded two new chromosome numbers forSaxifraga hirculusL., viz. the diploid number 16 and the triploid number 24. This provoked a detailed cytotaxonomic study of the species as a whole. My results imply that it contains four subspecies, one nearctic diploid (subsp.propinqua), one Rocky mountain diploid (subsp.coloradensis), one palaearctic tetraploid (subsp.compacta), and one circumboreal, essentially tetraploid, subspecies (subsp.hirculus). A key, descriptions and distribution maps are provided for those taxa.Saxifraga hirculusis the sole representative of its group (seriesHirculoideaeof sectionCiliateae) reaching outside Central Asia and exemplifies the origin of Arctic taxa from a low latitude high mountain group–as well as speciation at

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1992.tb00280.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

THOMAS, V.&DAVE, Y., 1992.Structure and biology of nectaries inTabebuia serratifoliaNichols (Bignoniaceae).Tabebuiahas both floral and extrafloral nectaries, situated on the petiole, bract, calyx, around the ovary and on the pericarp. The floral nectary present around the ovary base is differentiated into epidermis, secretory zone and sub‐secretory zone. It is supplied by phloem strands up to the secretory zone. A mature extrafloral nectary consists of a single large basal cell and a head comprising a layer of vertically arranged elongated cells. Starch, protein and lipid are present in the floral nectary. The major insect visitors to both types of nectaries are honey bees, houseflies and ant

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1992.tb00281.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

UNDER, H. P., 1992.The structure and evolution of the female flower of the African Restionaceae. The anatomical details of the gynoecium and perianth of the African Restionaceae are described. The same basic pattern of stylar and ovular vascular traces is found throughout the group. Variation in the number of fertile locules is the result of several reduction sequences. The most common sequence is the loss of the fertility of locules, followed by the loss of the infertile locules. These carpels are still represented by the stylar vascular traces. In different lineages, different locules become sterile. A second form of reduction is fusion of carpels. This occurred in only one lineage. The variation in the structure of the ovary walls is discussed, and three different types of ovary wall construction are demonstrated. The anatomical construction of the tepals is briefly mentioned, but it is apparent that the sample is too small for confident interpretation. Variation in ovary structure is shown to be largely consistent with the phylogeny and classification of the group. However, the relationship betweenThamnochortusandStaberohamay need re‐evaluation, and the status ofCalopsisas a monophyletic group distinct fromRestiois questione

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1992.tb00282.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

HAY, A., 1992.A new Australian genus of Araceae, with notes on generic limits and biogeography of the Areae. A monotypic aroid genus is described from Melville Island, Northern Territory, Australia. The genus is diagnosed in the tribe Areae by its tubular spathe base divided into two chambers by an annular septum. The genus is most closely related toSauromatumand to some Asiatic, not Australian, species ofTyphonium. It is proposed that the geography of the Areae (includingArum, Dracunculusetc.) may now suggest a Gondwanan (rather than Laurasian) and hence Cretaceous (rather than much more recent) origin for the tribe, and its dual arrival in Malesia.

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1992.tb00283.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY