These species have been traditionally clustered in morphological groups (e.g., Heyer 1970, L. melanonotus group; Heyer 1973, L. marmoratus group; Heyer 1978, L. fuscus group; Heyer 1979, 2005, L. pentadactylus group; Heyer 1994, L. podicipinus-L. wagneri group), without a phylogenetic framework.