title: Philometrids of the southern flounder Paralichthys lethostigma: a multidimensional approach to determine their diversity.
abstract: Two species of philometrid nematode, Philometra overstreeti and Philometroides paralichthydis, infect the southern flounder, Paralichthys lethostigma. Individuals of P. overstreeti are located between the teeth and inside the bony part of the branchial arches of the fish. Individuals of P. paralichthydis are associated with the bones of the buccal cavity and among muscles that control the dorsal and anal fins. Sequencing of part of the cytochrome oxidase I gene revealed 4 distinct genetic clades, each corresponding exactly to the 4 respective locations of the parasites in the host, suggesting the need for taxonomic revision. We hypothesized that each clade represented a separate species and, because the worms are morphologically indistinguishable, compared population level parameters of the clades comprising each currently recognized species. For each currently recognized species, the presence of worms from 1 clade was negatively correlated with the presence of worms from the other. Results also indicated significant differences between the clades in prevalences relative to both biotic and abiotic factors. Results clearly indicated major differences in the ecology of the philometrids constituting each clade. Taken as a whole, molecular and ecological data support the contention that the 4 genetic clades are likely 4 distinct species.
authors.affiliation: Department of Biology, College of Charleston, Fort Johnson Road, Charleston, South Carolina 29412, USA. deburoni@cofc.edu
authors.forename: Isaure
authors.initials: I
authors.lastname: de Buron
authors.forename: Scott G
authors.initials: SG
authors.lastname: France
authors.forename: Vincent A
authors.initials: VA
authors.lastname: Connors
authors.forename: William A
authors.initials: WA
authors.lastname: Roumillat
authors.forename: Lam C
authors.initials: LC
authors.lastname: Tsoi
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018509:DNA, Helminth / Q000737:chemistry; D017176:Dracunculoidea / Q000145:classification* / Q000235:genetics; D003576:Electron Transport Complex IV / Q000235:genetics; D005260:Female; D005393:Fish Diseases / Q000453:epidemiology / Q000469:parasitology*; D005432:Flounder / Q000469:parasitology*; D014644:Genetic Variation; D006239:Haplotypes; D008297:Male; D010802:Phylogeny; D015995:Prevalence; D016415:Sequence Alignment / Q000662:veterinary; D013022:South Carolina / Q000453:epidemiology; D017205:Spirurida Infections / Q000453:epidemiology / Q000469:parasitology / Q000662:veterinary*
chemical_list: D018509:DNA, Helminth; D003576:Electron Transport Complex IV