Article: A conodont, thelodont and acanthodian fauna from the lower Prídolí (Silurian) of the Much Wenlock area, Shropshire

Conodonts, thelodonts and acanthodians have previously been collected from the Pridoli of Shropshire (Welsh Borderland) from bone beds such as the Ludlow Bone Bed. In general, specimens collected from these types of deposit are very abraded and make taxonomic studies difficult. This contribution describes well preserved thelodont microelements from two samples from the Downton Castle Sandstone Formation (Pridoli, Silurian) of the Much Wenlock area of Shropshire. Head scales, a wide variety of transitional scales, and pore scales of the lateral line sensory canals of the thelodont Paralogania ludlowiensis (Gross) are described for the first time. A new acanthodian Nostolepis linleyensis sp. nov. and elements from the apparatus of the conodont Ozarkodina?hemensis sp. nov. are documented from the same samples. The thelodonts in both samples are typical of upper Ludlow-Pridoli faunas from across the Welsh Borderland, and are also present in smaller numbers in the Ludlow Series of Gotland, Sweden, Saaremaa Island, Estonia, and in Latvia and Lithuania. The conodont O? hemensis sp. nov. is restricted to the Much Wenlock area of Shropshire. The co-occurrence of well preserved elements of conodonts and thelodonts suggests that they were deposited fairly rapidly with little or no re-working and that a restricted marine environment prevailed in the early Pridoli in the Much Wenlock area of Shropshire.