Crisp & Chandler, Paraphyletic species 
817 
metaspecies 
I 
monophyletic 
species 
monophyletic monophyletic 
species species 
-1 I-1 
paraphyletic monophyletic 
species species 
metaspecies 
unresolved monophyletic 
after testing species 
Fig. 1. Illustration of monophyletic species, paraspecies (paraphyletic) and metaspecies (unresolved), 
a. Initial phylogeny showing a metaspecies as sister-group to a monophyletic species. The 
metaspecics has no apomorphic characters except 1, which it shares with its sister species. The 
monophyletic species has an autapomorphy, character 2. b-d, Possible outcomes following cladistic 
analysis of populations in a. b, A new symapomorphy (character 3) is found for populations 
comprising the metaspecies, which is now recognised as a monophyletic species, c, A new 
synapomorphy (character 4) is found which is shared by two populations of the metaspccies and 
the monophyletic sister species. Tire original metaspecies is now recognised to be paraphyletic. 
d. No further apomorphies are found, and the metaspecies remains unresolved. These definitions 
apply equally to subspecies. Terminal branches represent populations. Solid bars represent original 
apomorplries; open bars represent additional apomorphies discovered following cladistic analysis. 
