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Telopea Vol. 6(4): 1996 
Estimating paraphyly from absence of autapomorphy is subject to the following 
sources of error. First, a metaspecies may have a cryptic autapomorphy which 
remains undiscovered. In other words, a metaspecies is also potentially monophyletic. 
This will lead to overestimation of the number of paraphyletic taxa. Second, a 
feature that appears to be an autapomorphy in a species treated as an undivided 
taxon may prove to be homoplastic when cladistic analysis is done at a lower level. 
H. annuus 
H. petiolaris 
ssp. petiolaris 
H. petiolaris 
ssp. fallax 
H. neglectus 
Fig. 6. Phylogeny of populations of Helianthus petiolaris and H. neglectus (Rieseberg et al. 1991; 
Rieseberg & Brouillet 1994). This is the most parsimonious tree derived from chloroplast and 
nuclear ribosomal DNA restriction site polymorphisms (consistency index = 1). Outgroup is 
H. annuus. Note that H. neglectus is metaphyletic, H. petiolaris and its subsp. fallax are both 
paraphyletic, and H. petiolaris subsp. petiolaris is metaphyletic. 
