Seed morphology and anatomy of Austrotaxus spicata (Taxaceae) and its systematic position

The anatomy and ultrastructure of seed envelopes of a New Caledonian endemic Austrotaxus spicata were examined for the first time. The systematic position and phylogenetic relations of Austrotaxus were analysed in light of these data. The structure of aril and spermoderm were investigated to demonstrate the similarities with Phyllocladus as well as with Taxus and Pseudotaxus . On the basis of all female reproductive organ characters, Austrotaxus appeared to be fairly isolated and its placing in the independent family Austrotaxaceae was confirmed from the standpoint of comparative anatomy of the seed coat. Taking into consideration that the heterobathmy of features can be the most distinctively traced in the structure of reproductive organs, evaluating the extent of evolutionary advancement of Austrotaxus seems to be rather difficult. However, it is evident that the relationship of Austrotaxus either with Taxaceae or with Podocarpaceae s.l . is considerably remote.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 437–443.