Anisakid nematodes in Trichiurus lepturus and Saurida undosquamis (Teleostea) from the South-West Indian Ocean: Genetic evidence for the existence of sister species within Anisakis typica (s.l.), and food-safety considerations

• DOI: 10.1016/j.fawpar.2022.e00177
• Publication Date: 2022-08-23T03:25:13Z
• Authors: Paolo Cipriani; Lucilla Giulietti; Salome Daniel Shayo; Julia E. Storesund; Miguel Bao; Marialetizia Palomba; Simonetta Mattiucci; Arne Levsen
• Keywords: Anisakidae; Anisakis; Monophyly; Sister group

Nematode parasites of the genus Anisakis (Nematoda, Anisakidae) are considered among most important biological hazards in seafood products worldwide. In temperate and tropical waters, common species appears to be typica, generally found around viscera sporadically flesh various fish host species. This study investigated infection sites genetic diversity A. typica infecting commercial fishes from South-West Indian Ocean. Largehead hairtail (N = 20) brushtooth lizardfish 72) fished off Tanzania were inspected for anisakid nematodes by UV-press. A subsample 168 identified sequence analyses cox2 mtDNA gene ITS region rDNA. The (s.l.) 166), Pseudoterranova ceticola 1) paggiae molecularly identified. Phylogenetic analysis sequences based on both genes, indicated existence two distinct phylogenetic lineages forming well-supported clades. first clade comprised 12 specimens including individuals its type locality (central Atlantic Ocean). second comprising 154 specimens, clustered with reference retrieved GenBank one apparently undescribed taxon, i.e., sp. 1, var. indonesiensis. reciprocally monophyletic clades closely related correspond sister within (s.l.), presently as B. Two four fixed alternative nucleotide substitutions (SNPs), diagnostic positions, between taxa, respectively, at data, well their occurrence sympatry, strengthens hypothesis that actual represent pools. B musculature freshly examined T. lepturus S. undosquamis, suggests can migrate intra-vitam into flesh. Although zoonotic potential s.l. is still unclear, presence these musculature, edible part fish, raises health concerns consumers.