Fig. 1

Study site locations from the Mexican Gulf of Mexico: a Términos Lagoon, Campeche; Carmen-Pajonal-Machona Lagoon Complex, Tabasco; Mandinga Lagoon, Veracruz; and La Pesca Lagoon, Tamaulipas. The prevalence by PCR and by RFTM is shown for each locality in the pie charts. b Phylogenetic tree inferred by the Maximum Likelihood method (3000 bootstrap replicates) using the 28 rDNA-NTS sequences of Perkinsus marinus in C. virginica from sampled lagoons of the Gulf of Mexico and the GenBank database; the phylogenetic tree with the highest log likelihood (-1922.1161) is shown. There was a total of 308 positions in the final dataset. A rDNA-NTS sequence of P. olseni was used as a root (FJ626860.1). Each colour corresponds to the geographical collection site as well as its haplotype. Red and green colours correspond to P. marinus isolates from the Pacific coast of Mexico. Light blue and pink colours correspond to P. marinus isolates from the USA