The 1st embryological study was presented of Axinandra, a unique and problematic genus of Crypteroniaceae (order Myrtales). Although Axinandra clearly has the same basic embryological characteristics as other Myrtales, it is distinct from all other members of the order that have been examined in having an endothelium, i.e., integumentary tapetum, a feature that is usually a taxonomic characteristic at the familial level. Axinandra agrees with Melastomatoideae of Melastomataceae in its ephemeral (nonfibrous) endothecium, a feature otherwise unknown in Myrtales. It differs from the family Melastomataceae as a whole, however, in its 2-nucleate tapetal cells. Whether any of these features are shared with the genera Crypteronia and Dactylocladus, with which Axinandra is grouped to form the family Crypteroniaceae, or with Rhynchocalyx and Alzatea, sometimes also assigned to the embryologically unknown family Crypteroniaceae, must await further investigation.