FOUNTAIN, M.P.; HRANITZ, J.M.; VENN, C.; KLINGER, T.S.; Bloomsburg University; Bloomsburg University; Bloomsburg University; Bloomsburg University: Analysis of VNTR Locus Variation in Two Species of Gooseneck Barnacle (Lepas)

Several species of the gooseneck barnacle (Lepas) have overlapping distributions in the equatorial Pacific Ocean. Among these species, L. anatifera is the most widely distributed. L. anatifera is composed of two subspecies (L. a. anatifera and L. a. striatus) which exhibit morphological intermediates between subspecies. We investigated the underlying population genetic structure of the pelagic gooseneck barnacle in the equatorial Pacific Ocean using genetic variation at VNTR loci. Barnacles were collected from fixed buoys in the NOAA TAO array in April and September 1999. Analysis of VNTR loci, detected using a GT(n) probe, was conducted on 11 L. anatifera anatifera, 10 L. anatifera striatus, and two L. hillii collected from two locations separated by 70 degrees longitude. Similarity indices showed genetic differentiation (Lynch�s F(st) = 0.2131) among L. a. anatifera, L. a. striatus, and L. hillii. Pairwise comparisons of similarities indicate no significant differentiation between samples of L. a. anatifera and L. a. striatus but did distinguish both L. anatifera subspecies from L. hilli. A comparison between the eastern and western samples of pooled L. anatifera revealed no genetic differentiation (Lynch�s F(st) = 0.0266). There appears to be considerable genetic similarity between the two L. anatifera subspecies, suggesting that other factors (e.g., environmental conditions or growth rate) may be responsible for their differing morphologies.