Supplemental data for: Late Sandbian (Sa2) radiolarians of the Pingliang Formation from the Guanzhuang section, Gansu Province, China

<p>A diverse, well-preserved radiolarian assemblage is reported from the Sandbian age <i>Climacograptus bicornis</i> Graptolite Biozone. This new assemblage recovered from the Pingliang Formation in the Guanzhuang section, China includes six new species along with 13 other previously described taxa. <i>Geminusphaera</i> new genus incorporates <i>G. grandis</i> n. sp and <i>G. kongtongensis</i> n. sp. and is proposed for inaniguttids constructed from two distinct porous spheres bearing seven or more primary spines. <i>Protopylentonema</i> new genus is introduced to incorporate pylomate entactinarians with five-rayed initial spicules. It includes <i>P. ordosensis</i> n. sp. as well as <i>P. aperta, P</i>. <i>rimata</i> and <i>P</i>. <i>insueta</i> that were formerly assigned to <i>Kalimnasphaera</i>. Micro-computed tomography investigation of skeletal microstructure supports establishment of the new genera together with other new spumellarian species: <i>Haplotaeniatum implexa</i> n. sp., <i>Inanigutta quadrispinosa</i> n. sp. and <i>Kalimnasphaera pingliangensis</i> n. sp.. It also indicates that family level reassignment of <i>Etymalbaillella</i> from the Proventocitidae to the Ceratoikiscidae is appropriate.</p> <p>Global distribution of late Ordovician radiolarian occurrences highlights a strong preference for areas with equatorial to tropical sea surface temperatures. This must have led to ecological stress amongst radiolarian communities in adapting to global cooling in the Hirnantian.</p>