Nombre chromosomique d’angiospermes marocaines

Le nombre chromosomique de douze taxa appartenant à onze familles d’angiospermes marocaines sont rapportés: Achyranthes sicula n = 40; Bidens pilosa 2n = 60 et n = 30; Carrichtera annua 2n = 16; Clematis cirrhosa 2n = 16; Eryngium atlanticum n = 8; Parietaria judaica n = 13; Parietaria lusitanica subsp. lusitanica n = 10;  Scrofularia canina 2n = 24; Sixalix atropurpurea 2n = 16; Solanum sodomaeum n = 12;  Spergularia diandra 2n = 18 et Urginea maritima n = 30. La plus part des ces nombres sont rapportés pour la première fois sur des populations marocaines. Des microphotographies mitotiques ou méiotiques ainsi qu’un bref commentaire sont signalés pour chaque taxon.Chromosome numbers of twelve taxa from eleven families of Moroccan angiosperms are reported: Achyranthes sicula n = 40; Bidens pilosa 2n = 60 et n = 30;  Carrichtera annua 2n = 16; Clematis cirrhosa 2n = 16; Eryngium atlanticum n = 8; Parietaria judaica n = 13; Parietaria lusitanica subsp. lusitanica n = 10;  Scrofularia canina 2n = 24; Sixalix atropurpurea 2n = 16; Solanum sodomaeum n = 12;  Spergularia diandra 2n = 18 and Urginea maritima n = 30. Most of those numbers were reported for the fi rst time in Moroccan populations. Mitotic or meiotic metaphases microphotographs and brief comments are detailed for each taxa studied

Analyse de la Biodiversité floristique des zones humides du maroc. Flore rare menacée et halophile

Analysis of the moroccan wetlands floristical diversity: rare, threatened and halophilous flora. The moroccan wetlands flora shows a great floristical richness of these ecosystems, estimated at more than 670 species and subspecies (83 families) which can be supplemented by at least 272 others taxa considered rather as terrestrials but can colonize periodically these biotopes. This flora shows a rate of endemism close to 6,5 %, but the most fact is the great proportion of rare or threatened taxa (estimated at 34%). The halophilous flora was a subjet of particular comment considering the prevalence of the salt biotopes in Morocco, either by the number or the extent of the sites. It counts 115 species and subspecies distributed among 20 families

Novedades floristicas para el n de Marruecos

Se han seleccionado 29 novedades comarcales para el Catálogo de la flora del N de Marruecos, entre las especies recolectadas para el programa Semclimed en el país magrebí, durante la segunda parte de la campaña del mes de mayo de 2007. Estas campañas estaban orientadas a la recolección de semillas y la localización de poblaciones de especies raras y endémicas para el nuevo banco de germoplasma del Institut ScientiK que de la Universidad Mohamed V de Rabat, SEMCLIMED (Interreg IIIB Medocc-2005-05-4.1-E-110. Los recientes trabajos realizados en la catalogación de la flora del N de Marruecos permiten, a su vez, valorar el interés corológico de estas recolecciones

Disentangling environmental correlates of vascular plant biodiversity in a Mediterranean hotspot

We determined the environmental correlates of vascular plant biodiversity in the Baetic-Rifan region, a plant biodiversity hotspot in the western Mediterranean. A catalog of the whole flora of Andalusia and northern Morocco, the region that includes most of the Baetic-Rifan complex, was compiled using recent comprehensive floristic catalogs. Hierarchical cluster analysis (HCA) and detrended correspondence analysis (DCA) of the different ecoregions of Andalusia and northern Morocco were conducted to determine their floristic affinities. Diversity patterns were studied further by focusing on regional endemic taxa. Endemic and nonendemic alpha diversities were regressed to several environmental variables. Finally, semi-partial regressions on distance matrices were conducted to extract the respective contributions of climatic, altitudinal, lithological, and geographical distance matrices to beta diversity in endemic and nonendemic taxa. We found that West Rifan plant assemblages had more similarities with Andalusian ecoregions than with other nearby northern Morocco ecoregions. The endemic alpha diversity was explained relatively well by the environmental variables related to summer drought and extreme temperature values. Of all the variables, geographical distance contributed by far the most to spatial turnover in species diversity in the Baetic-Rifan hotspot. In the Baetic range, elevation was the most significant driver of nonendemic species beta diversity, while lithology and elevation were the main drivers of endemic beta diversity. Despite the fact that Andalusia and northern Morocco are presently separated by the Atlantic Ocean and the Mediterranean Sea, the Baetic and Rifan mountain ranges have many floristic similarities – especially in their western ranges – due to past migration of species across the Strait of Gibraltar. Climatic variables could be shaping the spatial distribution of endemic species richness throughout the Baetic-Rifan hotspot. Determinants of spatial turnover in biodiversity in the Baetic-Rifan hotspot vary in importance between endemic and nonendemic species