相关属的叶表皮微形态特征与粗叶木属植物较为相似。
The leaf epidermal morphology of the related genera in Rubiaceae is similar to Lasianthus .
粗叶木属的花粉单粒中等大小,绝大多数为圆球形。
The pollen grains are small to medium in size and spheroidal or subprolate in shape , and few are prolate .