Recent surveys of seed morphology in Lobelioideae (Campanulaceae) by Murata (1992, 1995) have led to a taxonomic revision of Lobelia L. and demonstrated the utility of such data in understanding systematic relationships within the subfamily. We have examined via scanning electron microscopy 52 additional seed accessions, emphasizing genera in which no species or only one species was examined by Murata. Foremost among these was the Hawaiian endemic Cyanea Gaudich., which comprises 75 species, only one of which (C. kunthiana Hillebr.) was examined by Murata. We examined 25 accessions, representing all major clades in the published phylogeny of the genus inferred from chloroplast DNA (cpDNA) restriction site analysis. Most were characterized by Type C morphology (the type reported by Murata for C. kunthiana), including species formerly segregated as Rollandia Gaudich., thus supporting synonymization of that genus. However, the species comprising the C. angustifolia-clade [sect. Delisseoideae (Hillebr.) Rock, s. str.] within the "Purple-fruited Clade" have a unique seed type with prominent bump-like lignose thickenings on the testa, thus offering a morphological marker for this molecularly-defined clade. We also examined seeds of the related Hawaiian endemics Brighamia H. Mann (both species) and Delissea Gaudich. (2 of 10 species) and found a second testal pattern (characterized by prominent transverse ridges) not reported by Murata. This supports the sister-status of these genera, a relationship originally revealed in the cpDNA phylogeny. The pattern observed in the C. angustifolia-clade appears to be intermediate between the Brighamia-Delissea pattern and Murata's Type C, supporting earlier hypotheses that C. angustifolia and its relatives lie nearest the ancestry of the genus.

Key words: Campanulaceae, Cyanea, Lobelioideae, scanning electron microscopy, seed morphology