engleski

A preliminary phylogenetic study of Cystoseira spinosa (Sauvageau) and Cystoseira adriatica (Sauvageau) (Fucales, Phaeophyceae) form Adriatic Sea using two mitochondrial molecular markers

The brown algae of the genus Cystoseira are among the most dominant and ecologically important species in the Mediterranean and Adriatic Sea. This evolutionary young genus is abundant in species and lower taxa, which exhibit a great morphological plasticity in different abiotic conditions. In this work we studied the phylogenetic relationship between the two Cystoseira species from the Adriatic Sea: C. spinosa Sauvageau and closely related C. adriatica Sauvageau, still unrecognized species and often quoted as a taxonomic synonym of C. spinosa. We successfully amplified and sequenced the two mitochondrial genes. A fragment of 23S rRNA showed no variability in all investigated specimens. The mt23S-tRNAVal intergenic spacer sequenced in eight specimens of C. adriatica and seven specimens of C. spinosa revealed three haplotypes (A, B, and C). The haplotype A was the most frequently found ; in five C. adriatica and five C. spinosa specimens. The haplotype B was found in three C. adriatica samples, whereas the haplotype C was found only in one C. spinosa specimen. When these sequences were compared with corresponding sequences of several other well established Cystoseira species (i.e. C. baccata, C. usneoides, C. elegans, and C. bracatta), the species specific separation was not obtained. Our preliminary results thus suggest a limited value of the mt intergenic spacer for the species level discrimination and a necessity of finding of a more appropriate molecular marker for the completing of this study.

Cystoseira spinosa (Sauvageau); Cystoseira adriatica (Sauvageau); mtDNA; molecular phylogenetics

nije evidentirano