Distribution and morphometric characteristics of Patella species (Archaeogastropoda) in Mersin-Viranşehir region of the Northeastern Mediterranean sea

Abstract

The main objectives of this study were to define the Patella species and determine their distribution and morphometry in Mersin-Viransehir region. 99 samples were collected from three stations, each being six m2. To determine the distribution of organisms in supralittoral, mediolittoral and infralittoral zones all individuals collected from these zones, were fixed in 4% formaldehyde and transported to laboratory for identification and morphometric measurements. First lateral teeth of radula and characteristic teeth appendages were used for taxonomic examinations. Two patella species, Patella caerulea and Patella rustica were identified in Mersin-Viransehir region. P.caerulea and P.rustica were constituted 88.89% and 11.11% of Patella species in the area respectively. P. caerulea was found in mediolittoral and upper infralittoral zones, whereas P.rustica was mainly distributed in supralittoral zones of the stations studied. Morphometric measurements of the specimens collected were carried out to find out whether these measurements could be used in species differentiation. Radula length to shell length ratio (RL:SL) of P.caerulea was calculated as 1.04 (range, 0.94-1.08) whereas this ratio was 2.03 (range, 1.97-2.08) for P.rustica. As a conclusion, it was suggested that RL:SL ratio should be used together with radula teeth characteristics for the identification of two Pa-tella species of Viransehir coast.