Circumpolles is a gymnosperm pollen type that is important in biostratigraphy and paleoenvironmental reconstruction. It characterizes the time between the middle Triassic to the middle Cretaceous Periods. This pollen has a unique morphology: it has a circular, equatorial colpus, which divides the pollen grain into two hemispheres. Circumpolles is also unique as it is the only gymnosperm with well developed nexinal columellae.