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Summary Baum, D. A. & Oginuma, K.: A review of chromosome numbers in Bombacaceae with new counts for Adansonia. - Taxon 43: 11-20. 1994. - ISSN 0040-0262. New chromosome counts are reported for all eight species of Adansonia. The six Malagasy species and the Australian species have 2n = 88, whereas the single African species, A. digitata, has 2n = 160. We review published counts for the family as a whole and conclude that there have been many inaccurate counts but that 2n = 86-92 appears to be general. A. digitata, Rhodognaphalon brevicuspe and Eriotheca pubescens are inferred to be polyploids. The tribe Durioneae, with counts of 2n = 28 and 2n = 56, is distant from the remainder of the family, as also suggested by morphological, biogeographic and molecular data.

Published chromosome numbers in Sonneratia and Duabanga are inconsistent and indicate the basic numbers of the two genera are x = 9 or 11 and x = 12, respectively. Chromosome number counts made in this study for three species of Sonneratia indicate 2n = 24, and for two species of Duabanga, 2n = 48. The base is established as x = 12 in both genera. Although the genera have accumulated numerous autapomorphies that lead them to be regarded in separate subfamilies Sonneratioideae and Duabangoideae of the Lythraceae s.l., they share karyologically similar chromosomes and a unique basic number for the family, which is x = 8 in the remaining subfamilies Punicoideae and Lythroideae. Sonneratia and Duabanga are regarded as among the most primitive genera of the Lythraceae s.l. A number of other myrtalean higher taxa also have x = 12. This base number is most likely the ancestral number for the order.