The present study reports the chromosome number and meiotic behaviour of 14 populationsbelonging to four taxa of Anchusa subgenus Buglossum Gusul. from Iran. All populationsshowed the chromosome number 2n= 4x= 32. It is the first meiotic study for A. subg.Buglossum. We discuss some habit form and evolutionary aspect in the light of cytogeneticdata. The origin of polyploidy (auto-allopolyploidy)...

Surveys were carried out to determine species composition and host range of powdery mildews (Erysiphaceae) in Gilan province, Iran. Twenty seven taxa were identified. Among them Erysiphe circaeae, E. punicae, E. urticae, Microsphaera erlangshanensis, M. multappendicis, M. trifolii and Podosphaera clandestine/ var. cydonia are new to Iran. Parietaria officinalis and Phuopsis stylosa are new host...

The early MIS 3 (55-40 Kyr BP associated with Middle Palaeolithic archaeology) bird remains from Pin Hole, Creswell Crags, Derbyshire, England are analysed in the context of the new dating of the site's stratigraphy. The analysis is restricted to the material from the early MIS 3 level of the cave because the upper fauna is now known to include Holocene material as well as that from the Late Gl...

The diatom composition on some Charophyceae taxa was investigated in different freshwater ecosystems in Bosnia and Herzegovina, Croatia and Montenegro during 2007. A total of 91 taxa belonging to 37 genera were identified. The genus Gomphonema with 9 taxa was the most diverse, followed by Navicula (7), Nitzschia, Pinnularia and Gyrosigma (5). The number of taxa at the localities varied from nin...

The present paper provides the first systematic and comprehensive account of the flora of Solapur district of Maharashtra (India). The flora of this region demonstrates a wide range of species diversity and growth forms. The vegetation of the district mainly represents tropical dry deciduous forests, thorny open scrub and vast grasslands. During the present work, a total of 1441 taxa belonging ...

The concept of a "potential taxon" as a nameand literature-related data area in botanical databases is introduced. A potential taxon is a name with taxon circumscription information attached to it by means of one or more literature references. As a compromise solution between linking information in database systems entirely to specimen data or only to accepted names, using potential taxa can ef...

Abundance and specificity are two key characteristics of species distribution and biodiversity. Theories of species assembly aim to reproduce the empirical joint patterns of specificity and abundance, with the goal to explain patterns of biodiversity across habitats. The specialist-generalist paradigm predicts that specialists should have a local advantage over generalists and thus be more abun...

It is well known among phylogeneticists that adding an extra taxon (e.g. species) to a data set can alter the structure of the optimal phylogenetic tree in surprising ways. However, little is known about this "rogue taxon" effect. In this paper we characterize the behavior of balanced minimum evolution (BME) phylogenetics on data sets of this type using tools from polyhedral geometry. First we ...