http://worldcat.org/entity/work/id/8041096

Comparative anatomy and systematics of twelve woody Australasian genera of the Saxifragaceae

Vegetative anatomical data are provided for twelve woody saxifragaceous genera from Australasia. These data are used, where possible, to determine the taxonomic position of these plants. The twelve genera are Tetracarpaea, Ixerba, Bauera, Anopterus, Cuttsia, Abrophyllum, Carpodetus, Argophyllum, Corokia, Donatia, Anodopetalum and Aphanopetalum. Typically these taxa possess dorsiventral leaves with uniseriate epidermides and anomocytic stomatal apparatuses. The nodal pattern is either unilacunar, one-trace or trilacunar, three-trace. The wood possesses angular, solitary pores, long vessel elements with oblique, scalariform perforation plates, tracheids with spiral thickenings and sparse axial parenchyma. Cuttsia, Abrophyllum, Carpodetus, Ixerba, Anopterus, Corokia and Argophyllum possess most or all of eleven anatomical features of an archetypical woody saxifrage. While wood anatomy is similar among Tetracarpaea, Bauera and an archetypical woody saxifrage, leaf anatomy is distinctive for each group. Donatia, Anodopetalum and Aphanopetalum possess few anatomical features of an archetypical woody saxifrage. Ixerba is anatomically isolated from the Brexioideae, but is similar to Anopterus in the Escallonioideae. Cuttsia and Abrophyllum are very similar anatomically and closely related. Anatomical data do not support the maintenance of the tribe Argophylleae of the Escallonioideae which includes Carpodetus, Corokia and Argo- phyllum. Carpodetus is more similar anatomically to Cuttsia and Abrophyllum than to Corokia and Argophyllum. Corokia and Argophyllum are very similar anatomically and probably closely related, but their taxonomic position remains obscure. Anatomical data support the union of the genus Argyrocalymma with Carpodetus, and the union of the genus Colmeiroa with Corokia. Tetracarpaea and Bauera are anatomically distinctive and isolated genera and may deserve familial status. Tetracarpaea is more closely allied to the Saxifragaceae based upon its wood anatomy, while Bauera is more closely allied to the Cunoniaceae because of its oppo- site leaves and foliaceous stipules. The nodal, leaf and wood anatomy of Anodopetalum is more similar to that of the Cunoniaceae than to that of the Saxifragaceae. Aphano- petalum and Donatia are readily distinguishable and isolated from the Saxifragaceae, but their taxonomic positions remain obscure. Donatia should probably be placed in its own family, but Aphanopetalum remains an enigma.

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