The number of salmonid taxa within some genera (e.g. Salmo, Salvelinus, and Coregonus) listed in various taxonomic databases (e.g. Fishbase or Eschmeyer's Catalog of Fishes) has increased very rapidly over the past 15-20 years. Many of these taxa are not widely accepted across the international community and are associated with very sparse data, leading to significant difficulty in accurately carrying out Red List assessments. The SSG strongly recommends a rigorous evaluation of the validity of these species designations, which can have real implications where legal protection is reflected by the use of these binomial taxonomic names.

Listed as Extinct because the species has not been found since the 1960s, despite extensive surveys and fish harvests.

Historically, this species occurred in the North American Great Lakes: Michigan and Huron.

No occurrences (subpopulations) remain. This species went extinct in the 1960s.

This species occurred in large lakes at depths of 30-185 m (rarely caught at less than 64 m).

Decline possibly due initially to overexploitation, then to effects of sea lamprey and hybridization with congenerics (Day 1981, Becker 1983, Miller et al. 1989).

Formerly this was a commercially important species.

This species is extinct and so does not require protection or major management or monitoring.