A trilobite fauna from the highest Shineton Shales in Shropshire, and the correlation of the latest Tremadoc

A rich fauna dominated by trilobites and calcified chordates has been collected in Shropshire from the Arenaceous Beds, the highest member of the Tremadoc Shineton Shale Formation, and hitherto regarded as poorly fossiliferous. This fauna shows that shelf conditions persisted longer in Shropshire than has been supposed. It is likely that even younger Tremadoc is cut out at the unconformity below the Caradoc in the Shineton Inlier. The correlation of the later Tremadoc is reviewed, and the nomenclature of British Tremadoc biozones is revised. The trilobites described here are a mixture of previously known and new forms. The nameShumardia (Conophrys) salopiensisCallaway is revived for British material traditionally assigned to the Scandinavian speciesShumardia pusilla(Sars), from which it is distinct. The new taxaLitagnostus meniscussp.nov.,Apatokephalus sarculumsp.nov. andSkljarella cracenssp.nov. are described. The type species ofAsaphellus, A. homfrayiandLeptoplastides, L. salteri, are redescribed, andGeragnostus callavei, Pseudokainella impar, andParapilekiasp. are recorded. New information on the ontogeny ofS. (C.) salopiensisandA. homfrayiis given.LitagnostusandSkljarellaare recorded from the British Isles for the first time.