Gelli-grîn Calcarous Ash trilobites, lower beds (Ordovician of the United Kingdom)

Where: Wales, United Kingdom (52.9° N, 3.6° W: paleocoordinates 52.2° S, 18.4° W)

• coordinate based on nearby landmark

• local area-level geographic resolution

When: Diplograptus multidens - Dicranograptus caudatus graptolite zone, Gelli-grîn Formation (Lower Bala Group), Longvillian (457.2 - 455.0 Ma)

• above Pont-y-Ceunant Ash member and below those yielding Chasmops cambrensis. Calcareous Ashes

• member-level stratigraphic resolution

Environment/lithology: marine; calcareous ash and blue mudstone

• Calcareous ash with subsidiary dark blue ashy mudstones. [Bassett et al 1966, Quart J Geol Soc 122: 219-271]

Size class: macrofossils

Preservation: mold/impression

Reposited in the BMNH

Primary reference: H. B. Whittington. 1968. The Ordovician trilobites of the Bala Area, Merioneth. Part IV. Monograph of the Palaeontographical Society 122(520):93-138 [M. Hopkins/M. Hopkins]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 188590: authorized by Melanie Hopkins, entered by Melanie Hopkins on 08.09.2017

Creative Commons license: CC BY (attribution)

Taxonomic list

 Odontopleurida - Odontopleuridae
 Phacopida - Acastidae
Kloucekia apiculata McCoy 1851 trilobite
 Phacopida - Homalonotidae
Brongniartella minor Salter 1852 trilobite
 Phacopida - Calymenidae
Flexicalymene cf. caractaci Salter 1865 trilobite
 Trinucleida - Trinucleidae
Broeggerolithus nicholsoni Reed 1910 trilobite
 Lichida - Lichidae
"Platylichas nodulosus" = Allolichas nodulosus
"Platylichas nodulosus" = Allolichas nodulosus McCoy 1851 trilobite