Keisley (Ordovician of the United Kingdom)

Where: England, United Kingdom (54.6° N, 2.5° W: paleocoordinates 44.1° S, 16.3° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Paraorthograptus pacificus graptolite zone, Upper Member (Keisley Formation), Rawtheyan (448.8 - 445.2 Ma)

• The entire formation is almost exactly correlative with the Boda Limestone, and stretches from the D. complanatus zone to the M. extraordinarius zone (Rawtheyan to Hirnantian, or Ka4 - Hi1). These beds seem to be from the P. pacificus zone.

• group of beds-level stratigraphic resolution

Environment/lithology: reef, buildup or bioherm; lithified limestone

• isolated carbonate mud mound.
• "Orchard (1980) recognized two informal subdivisions of the Keisley Limestone, namely a lower part of dark, muddy, nodular carbonates and siltstones, and an upper part of paler, crystalline limestone. This upper part has yielded the conodonts dealt with [in Bergström & Ferretti 2015] as well as most of the collections assembled by Rhodes (1955), Orchard (1980) and Aldridge (Orchard 1980). For further locality details, see Owen and Rushton (1999)." Bergström & Ferretti note that the shelly fossils almost certainly were collected from this level.

Size classes: macrofossils, mesofossils

Primary reference: E. Warburg. 1925. The Trilobites of the Leptæna Limestone in Dalarne. Leptæna Limestone Trilobites 1-446 [B. Kröger/B. Kröger/M. Hopkins]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 161737: authorized by Björn Kröger, entered by Björn Kröger on 11.09.2014, edited by Pete Wagner

Creative Commons license: CC BY (attribution)

Taxonomic list

Crinoidea
 Myelodactylida - Iocrinidae
Ristnacrinus sp.2 Opik 1934 Sea lily
Trilobita
 Harpetida - Harpetidae
"Harpes costatus" = Hibbertia costatus
"Harpes costatus" = Hibbertia costatus Angelin 1854 trilobite
 Lichida - Lichidae
Lichas laciniatus Wahlenberg 1818 trilobite
 Phacopida - Cheiruridae
Sphaerocoryphe punctata Angelin 1854 trilobite
Sphaerexochus calvus Mc Coy 1846 trilobite
Pseudosphaerexochus conformis Angelin 1854 trilobite
Cheirurus glaber Angelin 1854 trilobite
Holotrachelus punctillosus Törnquist 1884 trilobite
Gastropoda
 Murchisoniina - Loxonematidae
Loxonema striatissimum n. sp.3 Reed 1897 snail
 Murchisoniina - Trochonematidae
"Eunema carinatum" = Globonema carinata3
"Eunema carinatum" = Globonema carinata3 Angelin and Lindström 1880 snail
 Euomphalina - Platyceratidae
"Cyclonema rupestre" = Cyclonema rupestre3, "Cyclonema sulciferum" = Cyclonema rupestre3
"Cyclonema rupestre" = Cyclonema rupestre3 d'Eichwald 1856 snail
"Cyclonema sulciferum" = Cyclonema rupestre3 d'Eichwald 1856 snail
 Euomphalina - Helicotomidae
Palaeomphalus obtusangulus1 Angelin and Lindström 1880 snail
 Euomphalina - Holopeidae
Holopea concinna3 McCoy 1862 snail
Rhynchonellata
 Orthida - Dicoelosiidae
Strophomenata
 Strophomenida - Anopliidae