摘要：The biostratigraphically important Permian radiolarian genera
Pseudoalbaillellasensu stricto and
Follicucullus (Follicucullidae, Polycystinea) are discriminated by morphological gaps in their wings and segmentation. Previous statistical analyses demonstrated that
Longtanella fills morphological gaps between these two genera.
Longtanella has long been regarded as a junior synonym of
Parafollicucullus, and only a few species have been described. Herein several true
Longtanella species are recognized from South China, and eight new species and five indeterminate species are described and illustrated to prove the validity of the genus
Longtanella. In addition, a new genus,
Parafollicucullinoides gen. nov., is described. Their palaeogeographic distributions and living environments are explored by applying correspondence analysis (CA), with occurrence datasets of selected fusulinacean genera from the Japanese Islands, China and Sundaland. CA results indicate that
Longtanella was present to a limited extent in warmer conditions in the fusulinacean Province B and C during Kungurian–Roadian time, and possibly lived above the thermocline and below the deepest limit of fusulinaceans. The
Pseudoalbaillella and the
Follicucullus group preferred open ocean conditions, living below the thermocline and distributed not only in the ‘Equatorial Warm Water Province’, but also the northern peri-Gondwana Cool Water Province and the southern North Cool Water Province.
