Parasitological evidence of stocks of Paralichthys isosceles (Pleuronectiformes: Paralichthyidae) at small and large geographical scales in South American Atlantic coasts.

ALARCOS, A.J.; PEREIRA, A.N.; TABORARDA, N.L.; LUQUE, J.L.; TIMI, J.T.

FISHERIES RESEARCH

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2016 vol. 173 p. 221 - 228

0165-7836

tThree stocks of the flounder Paralichthys isosceles Jordan, 1861 were identified in the southwesternAtlantic by using their parasites as biological markers. Comparisons (pemutational multivariate anal-yses of variance and canonical analysis of principal coordinates) of 78 flounders caught simultaneouslyat two close localities in Brazil (Cabo Frio and Niteroi) and previously published data of 51 fish fromArgentina (Necochea) allowed testing the value of parasite tags as discriminators at both small and largespatial scales. A total of 5925 metazoan parasites belonging to 17 species were found in Brazilian samples.Parasite assemblages varied across localities in terms of species richness and presence and abundance ofindividual species. Multivariate analyses of presence and abundance of long-lived parasites resulted inclear dissimilarity patterns across all samples. Significant differences were also observed when the entireparasite assemblages were compared between both Brazilian samples. The best discriminator species atboth spatial scales were represented by unspecific parasites, broadly distributed among fish species in theregion. These indicator species apparently display recurrent spatial patterns across host species, beingtherefore expected to serve as suitable tags for population studies of other resources. Parasites consti-tute valuable tools to be included in further holistic stock identification studies, which may eventuallyallow proactive mitigation and conservation strategies for many short scale artisanal fisheries in thesouthwestern Atlantic coasts, which are facing severe risks of overexploitation and collapse.