Wood anatomy of the single species of Canacomyrica (hitherto not studied) shows that it belongs in Myricaceae, although it differs from other genera in several respects (axial parenchyma grouped in bands or columns as well as diffuse; Heterogeneous Type I rays; more numerous bars per perforation plate). The latter two features are primitive for the family. The four genera (Canacomyrica, Comptonia, Morella, and Myrica s.s.) differ from each other not only by qualitative features but by quantitative features (feature means in genera mostly non-overlapping). Wood of Comptonia and Myrica s.s. lacks chambered crystals in axial parenchyma and ray crystals. Wood of Myrica s.s. has tracheids in late-wood but fiber-tracheids in earlywood. Diagnostic generic summaries are presented. Features of Myricaceae such as scalariform perforation plates, presence of (true) tracheids, ray types, chambered encapsulated crystals in axial parenchyma, and bark anatomy correspond with character states and expressions in Betulaceae, Casuarinaceae, Corylaceae, Juglandaceae (including Rhoipteleaceae), Ticodendraceae and, to a lesser extent, Fagaceae and Nothofagaceae. This grouping of families can be found as Fagales in recent DNA trees. The predominance of tracheids in basal Fagales such as Myricaceae and Ticodendraceae suggests that origin of vasicentric tracheids which occur in combination with libriform fibers in Fagaceae is the product of tracheid dimorphism. Low imperforate tracheid length to vessel element length ratios (F/V ratios) in Myricaceae are a probable indication of wood primitiveness. Quantitative vessel features of Myricaceae, as combined in Mesomorphy Ratio values, characterize wood of Myricaceae as a whole, but at the species level such values correspond to respective habitats; notably high vessel density in Comptonia may represent greater conductive safety appropriate to relatively dry habitats.
Carlquis, S. (2016). Wood and Bark Anatomy of Myricaceae: Relationships, Generic Definitions, and Ecological Interpretations. Aliso, 21(1), 7–29. https://doi.org/10.5642/aliso.20022101.03