Integrative taxonomy, distribution, and host associations of Geocenamus brevidens and Quinisulcius capitatus from southern Alberta, Canada

Two stunt nematode species, Geocenamus brevidens and Quinisulcius capitatus, were recovered from the potato growing regions of southern Alberta, described and characterized based on integrative taxonomy. Morphometrics, distribution, and host associations of both species are discussed. The Canadian populations of both species displayed minor variations in morphometrical characteristics (viz., slightly longer bodies and tails) from the original descriptions. The populations of G. brevidens and Q. capitatus species examined in this study are proposed as standard and reference populations for each respective species until topotype specimens become available and molecularly characterized. Phylogenetic analyses, based on partial 18S, 28S, and ITS sequences, placed both species with related stunt nematode species. The present study updates the taxonomic records of G. brevidens and Q. capitatus from a new location, southern Alberta, Canada, and will aid in the decision whether these stunt nematodes should be included in nematode management programs.