论文部分内容阅读
Although Hasle & Sims reviewed the genus Stellarima and emended its generic description, a detailed survey of its fossil and living species has yet to be conducted.The genus, usually observed in high latitude samples, is a rare taxon and specimens are frequently fragmented, with the most recognizable part of the valve being the group of central rimoportulae, so fragments of other parts of the valve are often difficult to identify.