An unusual crinoid-coral association from the Lower Carboniferous of Clitheroe, Lancashire

Abstract

A well-preserved calyx of the monobathrid camerate crinoid Amphoracrinus gilbertsoni (Phillips) from the Lower Carboniferous (Chadian, Visean) of Salthill Quarry, Clitheroe, Lancashire, is preserved in close association with a solitary rugose coral. Evidence for the coral being an epizoozoan on the crinoid includes its perpendicular orientation to the calyx, its position at the base of a free arm (B ray) in the AB interray, breakage of the crinoid plates around the coral (calyx ligamentation had not rotted post-mortem), and a growth deformity in the AB interray. The position of the coral indicates that, in life, it was elevated above the sea floor and directed into the prevalent water current by the crinoid. Its position, adjacent to a free arm and growth deformity of the AB interray suggest it was also a parasite on the adoral groove of the crinoid arm.

Lucky rugose corals on crinoid stems: unusual examples of subepidermal epizoans from the Devonian of Morocco

“…On the other hand, there is very little evidence for such a type of association between crinoids and solitary rugose corals (Brett et al. 1986, 2007; Donovan et al. 2005; Głuchowski 2005; Bohatý et al.…”

“…(1986, 2007) described an example of small rugose corals on crinoids: Stereolasma rectum attached itself like brackets on the columns of Eutaxocrinus whiteavesi from the Middle Devonian (Givetian) Otisco Shale. Donovan et al. (2005) studied one unidentified specimen of solitary Rugosa embedded within the calyx of Amphoracrinus gilbertsoni from the Viséan of Clitheroe, Lancashire.…”

“…Most of them represent interactions between colonial tabulate corals and crinoid stems (Hudson et al 1966;Galle & Prokop 2000;Głuchowski 2005). On the other hand, there is very little evidence for such a type of association between crinoids and solitary rugose corals (Brett et al 1986(Brett et al , 2007Donovan et al 2005;Głuchowski 2005;Bohatý et al in press). Brett et al (1986Brett et al ( , 2007 described an example of small rugose corals on crinoids: Stereolasma rectum attached itself like brackets on the columns of Eutaxocrinus whiteavesi from the Middle Devonian (Givetian) Otisco Shale.…”

“…Brett et al (1986Brett et al ( , 2007 described an example of small rugose corals on crinoids: Stereolasma rectum attached itself like brackets on the columns of Eutaxocrinus whiteavesi from the Middle Devonian (Givetian) Otisco Shale. Donovan et al (2005) studied one unidentified specimen of solitary Rugosa embedded within the calyx of Amphoracrinus gilbertsoni from the Viséan of Clitheroe, Lancashire. Głuchowski (2005) figured two swollen pluricolumnals of Schischcatocrinus creber infested by one to three specimens of solitary undissepimented rugose corals assigned to Adradosia sp.…”

The poorly illustrated crinoid

“…The origin of this reconstruction sadly emphasizes this lack of attention to detail. Rachel Jackson (Clitheroe Castle Museum, written communication 15 October, 2010) informed me that the museum’s reconstruction was based on one by Paul Kabrna, a colleague with whom I have published previously on the crinoids of Clitheroe (Donovan et al. 2005, 2006).…”