Figure 1.
Haplotype distribution and frequency map for Mnemiopsis leidyi.
Allele (inner circle for ITS) and haplotype (outer donut for COI) distribution map of Mnemiopsis leidyi. Each color indicates a different allele/haplotype. Private alleles/haplotypes are highlighted in grey. Population codes are described in Table 1.
Table 1.
Population code, sample size (N), number of haplotypes (n), haplotype diversity (h), nucleotide diversity (π), number of alleles (Na), observed (Ho) and expected (He) heterozygosity, and P-value for Hardy-Weinberg equilibrium (HWE) analysis; bold numbers correspond to populations deviating significantly (P<0.05) from HWE.
Figure 2.
Phylogenetic analyses of Mnemiopsis leidyi.
Phylogenetic and network relationship between the 17 haplotypes identified in the alignment of COI (A) Neighbor joining phylogenetic tree based on nucleotide divergence calculated using Tamura-Nei model. (B) Network relationships among haplotypes for native and introduced populations, inferred by statistical parsimony. Pie charts correspond to sampled haplotypes described in Figure 1. The size of the charts corresponds to the frequency of the haplotype among all samples. Black circles indicate missing haplotypes and each line represents a single mutation step. Colours show different locations for recovered haplotypes: green: native region, blue: Northern Europe, red: Ponto-Caspian region, and yellow: Mediterranean Sea.
Figure 3.
Rarefaction curves and Chao-1 estimates for Mediterranean Sea and putative source populations.
Sample-based rarefaction curves of native populations (green line, ±95% C.I.), Black-Azov Seas (black line, ±95% C.I.), and Mediterranean Sea (blue line, ±95% C.I.) for (A) COI haplotypes and (B) ITS alleles found in surveyed Mnemiopsis leidyi populations. Estimates of haplotype and allele richness (Chao-1, ±95% C.I.) are shown in each panel for native populations (green bar), Black-Azov Seas (black bar), and Mediterranean Sea (blue bar). Note the break in the y-axis scale.
Table 2.
Population subdivision according to pairwise FST values.
Figure 4.
Venn diagram illustrating shared haplotypes/alleles between regions.
Venn diagram showing COI haplotypes (A) and ITS alleles (B) sharing between Mediterranean and possible source populations from North America and Black-Azov Seas. Note that haplotype Ml01 and allele G from South America are excluded.