- Yalongipollis minutus
- Yalongipollis sp
- Yangzhoupollis rotundiporus
- Yangzhoupollis sp
- Yanichevskyites petropolitanus
- Yeguapollis
- Yeguapollis colporatus
- Yeguapollis prolatus
- Yeguapollis sp.1
- Yenjisapollis
- Yenjisapollis clausus
- Yenjisapollis formosensis
- Yenjisapollis granulatus
- Yenjisapollis minor
- Yenjisapollis ningduensis
- Yenjisapollis occultus
- Yenjisapollis rostralis
- Yenjisapollis rostrialis
- Yenjisapollis rotundatus
- Yenjisapollis sp
- Yenjisapollis triangularis
- Yichangia
- Yichangia biporosa
- Yichangsporites
- Yichangsporites liaoxiensis
- Yichangsporites sp
- Yichangsporites tricyclosus
- Yimaia recurva
- Yinia
- Yinia niutitangensis
- Yizhengopollis
- Yizhengopollis huichangensis
- Yizhengopollis songliaoensis
- Yizhengopollis triangulus
- Yizhengopollis yizhengensis
- Ynezidinium
- Ynezidinium brevisulcatum
- Ynezidinium latolineatum
- Ynezidinium malloyi
- Ynezidinium pentahedrias
- Ynezidinium waipawaense
- Yolkinigymnium
- Yolkinigymnium elongatum
- Yolkinigymnium expansum
- Yolkinigymnium lanceolatum