The Bornean assemblage of the genus Lithocarpus (Fagaceae) contains several novel modifications of the classic oak-acorn fruit type, which encompasses much of the generic level morphological variation. The shape variation in fruit type was adequately captured by continuous morphometric descriptors of radial outlines of fruit exocarp and receptacle. Both a principal components analysis of elliptic Fourier coefficients (EF-PCA) and eigenshape analysis (EGS) provided informative descriptors of shape variation. A neutral evolutionary model and restricted maximum likelihood was used to create a morphometric transformation series. Several important taxonomic and phylogenetic aspects were captured by these analyses. An independent molecular phylogeny of the ITS regions of the nuclear ribosomal DNA for the same exemplar species supported parallel derivations of a specialized fruit type, not apparent in the morphometric transformation series. This incongruence suggests convergent evolution of a complex fruit morphology between independent lineages. Conversion of morphometric series into matrix representations weighted by standardized branch lengths allowed a combined phylogenetic analysis with the molecular data which produced a single most parsimonious tree and supported two independent derivations of the specialized fruit type. The relative rates of change between morphology and molecules is not correlated between well-supported nodes and do not consistently deviate in one direction or the other. The molecular change from outgroup to ingroup is much greater than the morphometric change while transitions to the specialized fruit type involved large morphometric changes with little corresponding molecular change. The use of continuous morphometric shape descriptors significantly contributed to our understanding of fruit evolution in a morphologically difficult group.

Key words: comparative analysis, continuous morphometric characters, Eigenshape analysis, Fagaceae, Lithocarpus, matrix representation parsimony