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The genetic diversity within and among nine natural populations of Thymus hirtus Willd. subsp. algeriensis (Boiss. et Reut.) Murb. from different geographical and bioclimatic zones were assessed using Random Amplified Polymorphic DNA data. A total of 154 bands were generated from seven selected primers. 141 bands were polymorphic (P=91.56%). The genetic diversity within a population based on Shannon's index which was high (H'pop=0.307) and varied according to bioclimatic zones. A high genetic differentiation among populations (GST=0.335 and FST=0.296) was revealed, suggesting a population isolation and a low level of gene flow among them. The major proportion of the variation was attributable to individual differences within populations. The genetic structure is in accordance with geography distances. The Neighbour- joining tree based on Nei's and Li's genetic distance among individuals showed that individuals from each population clustered together. The UPGMA dendrogram based on FST values revealed three clusters each of them includes populations closuring to their geographical origin. The high genetic structure of populations resulted from genetic drift caused both by the habitat fragmentation and the low size of most populations. The in situ conservation should interest all populations. The ex situ conservation should be based on the collection of seeds rather within than among populations because of the maximum of variation was revealed within populations.
To assess karyological and morphometric diversity within Discoglossus pictus Otth 1837, morphometric and cytogenetic analyses were carried out on five populations from the northern Tunisia and Algeria. A total of eight morphometric adult traits were evaluated, tadpole oral disc structure was described and chromosome patterns were assessed by means of conventional staining and banding methods (C-, Ag-NOR and CMA₃ banding). Karyological data indicated the same chromosome and chromatin characters among the five populations. We observed also the same oral disk structure (LTRF: ⅔) in all studied Discoglossus tadpoles. However, we found significant differences in morphometric parameters of the specimens from these localities. Discriminant Function Analysis (DFA) of morphometric variables correctly classified 88% of individuals to their original localities. The pattern of morphometric variation does not match the genetic observation, which suggests that body shape differences result from the phenotypic plasticity correlated with local climatic factors.
Euthera fascipennis (Loew, 1854) is recorded from Tunisia for the first time. The puparium of this species was collected in a ruderal environment (a kind of sward) in the stem of the inflorescence of Thapsia villosa L., near a larval gallery of Acmaeoderella lanuginosa (Gyll.) (Coleoptera, Buprestidae). The female and the puparium are described and illustrated.
Disarticulated material from the Late Triassic Timezgadiouine Formation in the Argana Basin of Morocco represents a new taxon of silesaurid dinosauromorph, Diodorus scytobrachion gen. et sp. nov. D. scytobrachion can be distinguished from other silesaurids by the presence of anteriorly−canted teeth that decrease in size towards the anterior end of the dentary and a distinct lateral ridge running parallel to the dentary alveolar margin. In a phylogenetic analysis, D. scytobrachion is recovered as the sister−taxon to the Brazilian Sacisaurus agudoensis, nested deep within Silesauridae. This new taxon provides further evidence of a near−cosmopolitan range for basal dinosauriforms in the Late Triassic and further demonstrates the disparity of dental morphologies within Silesauridae.
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