The commission may, by rule, treat any species as an endangered species or threatened species even though it is not listed pursuant to section 481B.3 if it finds that the species so closely resembles in appearance a species which is listed pursuant to section 481B.3 and that enforcement personnel would have substantial difficulty in attempting to differentiate between the listed and unlisted species, and the effect of this substantial difficulty is an additional threat to an endangered or threatened species, or finds that the treatment of an unlisted species will substantially facilitate the enforcement and further the intent of this chapter.
C93, §481B.6