Phylogenetic relationships among Varestrongylus species and other Protostrongylidae. Most-parsimonious tree depicting the independence of Varestrongylus alces and other Varestrongylus species, and the reciprocal monophyly of sequences within each. The bootstrap consensus tree inferred from 5,000 replicates is taken to represent the evolutionary history of the taxa analyzed. Branches corresponding to partitions reproduced in less than 50% bootstrap replicates are collapsed. The percentage of replicate trees in which the associated taxa clustered together in the bootstrap test (5,000 replicates) shown next to the branches .