Middle to late Telychian (Silurian: Llandovery) graptolite assemblages of central Wales

Graptolite faunas from the uppermost turriculatus, crispus, griestoniensis, crenulata and spiralis Biozones of central Wales are described. Detailed collecting integrated with recent BGS mapping has demonstrated a new subzone of Torquigraptus carnicus in the uppermost turriculatus Biozone, a subdivision of the crispus Biozone into three successive subzones of, in ascending order: Monoclimacis? galaensis, Monograptus crispus, and Streptograptus sartorius; an informal subdivision of the griestoniensis Biozone into two successive assemblages, and the presence of faunas which can be assigned to the late Telychian crenulata and, probably, the spiralis Biozones. The compositions of these successive assemblages are outlined, and selected graptolites are figured and described. These include two new species: Monograptus pseudocommunis and Streptograptus whitei.