A re-evaluation of the phylogeny of Parelaphostrongylus Boev & Schulz, 1950 (Nematoda: Protostrongylidae)

The phylogeny of the genus Parelaphostrongylus was reconstructed using Elaphostrongylus rangiferi as an outgroup. Parelaphostrongylus is monophyletic and divided into two clades, one containing the meningeal worm, P. tenuis of white-tailed deer, and the other consisting of two muscle-inhabiting forms, P. andersoni and P. odocoilei of white-tailed and mule deer, respectively. Differences in biological features, including tissue migration route and prepatent period, are mapped onto the cladogram and discussed. Phylogenetic relationships among the host group, the Cervidae, are reviewed. It is suggested that E. rangiferi evolved in a Palaearctic cervid. Parelaphostrongylus probably co-speciated with Nearctic deer, Odocoileus spp. Host-switching from O. virginianus may explain the widespread occurrence of P. andersoni in Rangifer in North America.