| 1. | They are globose , subglobose , oblate and prolate in shape . the germination apertures are absent , or present and are irregularly poroid , 3 - colpate , 4 - colpate , 3 - 4 - colpate , pantocolpate and 3 - colporate . the exine ornamentation is spinulose , tuberculate , variously striate , striate - foveolate , striate - reticulate , rugose - sinuate , minutely reticulate and reticulate 条纹网状、皱波状、细网状和网状c沟膜近光滑、具小颗粒、具小刺状突起或具瘤状突起。 |