A founder effect in Blackfordia virginica in the United States and a comparison of Blackfordia virginica from the United States and Brazil

A founder effect was detected in Blackfordia virginica suggesting that it is an introduced species in the United States. Compared to Nemopsis bachei, a native hydrozoan, B. virginica exhibited a 0.03% average percent variation less than N. bachei with 3 fewer haplotypes. For COI B. virginica exhibited a 0.23% average percent variation of less than N. bachei with 7 fewer haplotypes. For ribosomal ITS1, B. virginica exhibited a 0.39% average percent variation higher than N. bachei. Both species had 2 haplotypes. For 16S, when compared to 30 other species of Hydrozoa, B. virginica had the lowest average percent variation at 0% with the fewest number of haplotypes. When compared to 14 other species for COI, B. virginica had the second lowest average percent variation for at 0.03% and the second lowest number of haplotypes. When B. virginica is compared to individuals collected in the United States and Brazil, the percent variation for 16S is 10.05% and for COI is 12.6% suggesting that specimens from Brazil are a different species.