Abstract The wood anatomy of corystosperms is fundamentally consistent with that of gymnosperms, yet their growth ring boundaries share anatomical features with extant angiosperms. This transitional morphology strongly supports the interpretation of corystosperms as an evolutionary intermediate between gymnosperms and angiosperms. Ecological reconstructions suggest that corystosperms were large evergreen trees with leaf retention periods of three to five years. They likely thrived in warm summer environments where prolonged foliage retention provided adaptive benefits.
Jiang et al. (Thu,) studied this question.