Biodiversity, systematics, and new taxa of cladid crinoids from the Ordovician Brechin Lagerstätte

Abstract

Upper Ordovician (Katian) strata of the Lake Simcoe region of Ontario record a spectacularly diverse and abundant echinoderm fauna known as the Brechin Lagerstätte. Despite recognition as the most taxonomically diverse Katian crinoid paleocommunity, the Brechin Lagerstätte has received relatively little taxonomic study since Frank Springer published his classic monograph on the “Kirkfield fauna” in 1911.Using a new collection of exceptionally preserved material, we evaluate all dicyclic inadunate crinoids occurring in the Brechin Lagerstätte, which is predominantly comprised of cladids (Eucladida and Flexibilia). We document 15 species across 11 genera, including descriptions of two new genera and four new species. New taxa include Konieckicrinus brechinensis n. gen. n. sp., K. josephi n. gen. n. sp., Simcoecrinus mahalaki n. gen. n. sp., and Dendrocrinus simcoensis n. sp.Although cladids are not commonly considered major components of the Early Paleozoic Crinoid Macroevolutionary Fauna, which is traditionally conceived as dominated by disparids and diplobathrid camerates, they are the most diverse major lineage of crinoids occurring in the Brechin Lagerstätte. This unexpected result highlights the important roles of specimen-based taxonomy and systematic revisions in the study of large-scale diversity patterns.UUID: http://zoobank.org/09dda7c2-f2c5-4411-93be-3587ab1652ab

A Hirnantian holdover from the Late Ordovician mass extinction: phylogeny and biogeography of a new anthracocrinid crinoid from Estonia

“…2018; Wright et al . 2020). Priscillacrinus is assigned to the family Anthracocrinidae along with several other genera that are recovered as closely related to Tallinnicrinus , including Rheocrinus Haugh, 1979, Gustabilicrinus Guensburg, 1984, and Anthracocrinus Strimple & Watkins, 1955 (Fig.…”

Niche evolution and phylogenetic community paleoecology of Late Ordovician crinoids

“…Subsequent collecting produced a large number of exceptionally preserved specimens that were used as the basis for a re-evaluation of the diversity of the fauna. These revisions of the fauna were covered in a series of recent publications that resulted in the recognition and description of 15 new species and 3 new genera, bringing the known diversity of Brechin crinoids to 27 genera and 39 nominal species (Cole et al, 2018(Cole et al, , 2020Ausich et al, 2018;Wright et al, 2019). Similar to the Bromide fauna, the Brechin also preserves a number of species belonging to other echinoderm classes (e.g., Sumrall & Gahn, 2006;Blake & Koniecki 2019, although most have not received comprehensive taxonomic assessment.…”

Paleocommunity composition, relative abundance, and new camerate crinoids from the Brechin Lagerstätte (Upper Ordovician)

“…Based on our series of comprehensive taxonomic re-evaluations (Ausich et al, 2018;Cole et al, 2018;Wright et al, 2019), including those presented here, the Brechin Lagerstätte is the most taxonomically diverse Katian crinoid fauna in the world. To the best of our knowledge, the Brechin Lagerstätte contains more nominal crinoid species and genera than the wellknown Middle Ordovician Bromide Formation of Oklahoma (Sprinkle, 1982; see Webster and Webster, 2014 (Sprinkle, 1982), the Brechin fauna is significant as one of the oldest, ecologically complex, and taxonomically diverse crinoid paleocommunities in the fossil record.…”

“…More recently, the extensive collection of crinoid material from the Bobcaygeon and Verulam formations near Brechin, Ontario produced a substantial new collection of exceptionally preserved crinoids. To better understand the taxonomic diversity and paleoecology of this Upper Ordovician crinoid community, we undertook a comprehensive taxonomic re-evaluation of the crinoids from the Bobcaygeon and Verulam formations, which has been documented in a series of recent papers (Ausich et al, 2018; Cole et al, 2018; Wright et al, 2019). This exceptionally preserved fauna has been identified as a Konservat-Lagerstätte and has been subsequently referred to as the Brechin Lagerstätte, in reference to the nearby town of Brechin, Ontario (Cole et al, 2018).…”

“…We present here the fourth and final systematic contribution in the series on crinoids from the Brechin Lagerstätte. The three preceding publications focused on taxonomy of diplobathrid camerates (Cole et al, 2018), disparids and hybocrinids (Ausich et al, 2018), and eucladids and flexibles (Wright et al, 2019). We evaluate the remaining camerate crinoids known from the fauna, including all monobathrids and a new diplobathrid camerate.…”