Phylogenetic Relationships

The systematic position of Illicium has received considerable attention. In most of the early taxonomic literature it was regarded as a member of the family Magnoliaceae (e.g., Bentham and Hooker 1862; Dalla Torre and Harms, 1900-1907), although this approach is rarely adopted today. The genus was subsequently excluded from the Magnoliaceae by Smith (1947) and Bailey and Nast (1948) on the basis of morphological and anatomical criteria, and Smith (1947) formally published the new familial name Illiciaceae solely for the genus Illicium. Both Smith (1947) and Bailey and Nast (1948) suggested a close relationship with the Schisandraceae, a family of scrambling and twining woody vines; this is reflected in all current angiosperm classification schemes (e.g., Dahlgren, 1980; Takhtajan, 1980; Cronquist, 1981; Thorne, 1992; Angiosperm Phylogeny Group, 1998), with most people using the ordinal taxon Illiciales collectively for the two families. Supportive data (generally interpreted using cladistic phylogenetic techniques) have been obtained from a wide variety of different sources, including general morphology (Donoghue and Doyle, 1989; Loconte and Stevenson, 1991), embryology (Hayashi, 1965), cytology (Ehrendorfer et al., 1968), phytochemistry (Sy et al., 1997), and the analysis of nucleic acid sequence data (Chase et al., 1993; Qiu et al., 1993; Soltis et al., 1997).

Analysis of morphological data has highlighted the Winteraceae as the closest relatives of the Illiciales (Donoghue and Doyle, 1989; Loconte and Stevenson, 1991). More recently, analysis of molecular data has contradicted this connection and revealed possibly closer relationships with the Austrobaileyaceae (Chase et al., 1993; Qiu et al., 1993; Soltis et al., 1997).

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