摘要:

Hyacinthella lazulinais described as new to science. The new species is closest toH. heldreichii, but has a different chromosome number, 2n = 22, and a vicariant distribution E of its sister species in southern Turkey. Distinguishing features and geographical distribution of the two species are discussed, and a map including all known localities is provided. A new key to the Turkish taxa has been constructed, and new chromosome counts for all but two species are included.

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1992.tb01838.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

A revised definition of complex polyandry is presented for the Magnoliatae. The differences between primary polyandry and secondary (complex) polyandry are clarified. Fascicled stamens are probably not primitive in Magnoliatae. Complex polyandry finds its origin by an increase of stamens in an oligandrous framework. Multiplications of stamens occur either on primary complex primordia, which follow the regular phyllotactic sequence in the flower, either on a girdling primordium (ringwall). The primary primordia may be fully developed before a secondary proliferation of stamens takes place or provide room for more stamens by a continuing growth process. This happens by the development of a staminal tube (e.g. Malvales) or by the growth of a hypanthium (e.g. Myrtales). A typical floral vasculature is developed concomitantly with complex polyandry. Stamen trunk bundles (stamen fascicle traces) are correlated with preformed complex primordia and the absence of a hypanthium. The inception of a ringwall is responsible for a higher complexity in vasculature and for obscuring the identity of the trunk bundles. The presence of a hypanthium does not permit trunk bundle formation because stamens develop on a limited section of the hypanthial slope. In that case the vasculature is characteristically represented by few large bundles linked with the perianth and the androecium. The distribution of complex polyandry is plotted on a Dahlgrenogram and presented in a table. The systematic relevance of complex polyandry is limited to the lower taxonomic (e.g. familial) levels.

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1992.tb01839.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1992.tb01840.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

Chromosome numbers from 17 Finnish populations of six taxa in theCarex flavacomplex were examined. Special attention was given to taxa claimed to be endemic to Fennoscandia. The meiotic counts forC. flavan = 30,C. viridulavar.viridulan = 35 and var.pulchellan = 35 are in accordance with previous reports. The counts forC. jemtlandican = 34, C.bergrothiin = 35, andC. kotilainin = 34 are new. The hybridC. flava×kotilainireveals severely disturbed meiosis with many uni‐ and multivalents. The results are briefly discussed in relation to morphological data.Carex jemtlandicashould evidently be included inC. lepidocarpa. Carex bergrothiiandC. kotilainibelong to the polymorphicC. viridula, but the latter probably consitute a specific cytoty

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1992.tb01841.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1992.tb01842.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

Pollen and seed morphology were examined in 54 diploid and allopolyploid populations representing 15 Nordic species of the taxonomically complex genusDraba.The pollen size was strongly correlated with chromosome number, but it was unreliable for inferring the exact ploidal level of individual populations. Five main pollen types were recognized based on sculpturing of the exine. Two populations ofD. lacteahad conspicuously different exine sculpturing, supporting a previous hypothesis based on molecular data that this hexaploid is polyphyletic and has been derived from various combinations of diploid species. The pollen morphological data are also consistent with the hypotheses that the 16‐ploidD. corymbosais an intersectional allopolyploid derived from the sectionsDrabaandChrysodraba, that the hexaploidD. cinereais a progenitor of the decaploidD. arctica, and thatD. crassifoliaandD. adamsiirepresent isolated allopolyploid lineages. The seed size and weight were only weakly correlated with chromosome number, but showed a close relationship to habitat ecology. The largest seeds were observed in species typical of closed habitats, in which seedling establishment probably is limited by competition with mosses. The seed coat surface had a characteristic verrucate reticulum, but the differentiation among species was vague or absent. The seed size and colour, however, distinguish some species, e.g., in theD. alpinacomplex, which otherwise are morphologically very simila

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1992.tb01843.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1992.tb01844.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

A small shrub,Euphorbia bariensisrelated toE. arbuscula, a sturdy shrub,E. pachycladarelated toE. consobrinaandE. nubica, and one with conspicuous bracts,E. papilionumrelated toE. cameronii, are described as distinctive new endemic‐species from northeast Somalia. A new endemic,E. dhofarensisrelated toE. larica, is also described from the Dhofar region of Oma

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1992.tb01845.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1992.tb01846.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

A small prostrate herb,Euphorbia salsicola, a woody shrublet with curious tubers,E. scatorhiza, and a small tree with decorative bracts,E. thulinii, are described as new species ofEuphorbia.Within subgenusLyciopsisthe morphological variability ofE. cuneatain Somalia is discussed and a new subspeciescretaceais described.E. gypsophila, a closely related but distinct species found only on gypsum is also described as new, together withE. dunensis, a shrublet from the coastal dunes andE. tripartita, another shrub in the same subgenus related toE. matabelensis.As far as present records show, all the new taxa are endemic in Somalia.

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1992.tb01847.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY