Camptocrinus Wachsmuth & Springer or Neocamptocrinus Willink? Distinctive crinoid columnals from the Permian of Timor

Abstract

Schoor, D.I.E., Donovan, S.K. & Webster, G.D. 12 September 2019. Camptocrinus Wachsmuth & Springer or Neocamptocrinus Willink? Distinctive crinoid columnals from the Permian of Timor. Alcheringa 44, 56–63. ISSN 0311-5518

Only one nominal species of the monobathrid camerate crinoid Camptocrinus Wachsmuth & Springer is known from the Permian of Timor, namely Camptocrinus indoaustralicus Wanner. The varied morphologies of disarticulated columnals may be due to variation within the xenomorphic column of this species, the presence of one or more additional species and/or the co-occurrence of the monobathrid Neocamptocrinus Willink. Herein, columnals are grouped into those with a strong elliptical shape; those with an inflated and oval outline; and those intermediate between these two extremes. A single specimen is encrusted by the auloporid tabulate coral Cladochonus? sp. Even separating Camptocrinus and Neocamptocrinus on the basis of more complete specimens is problematic. Neocamptocrinus is defined by its numerous small plates in an extended tegmen, which is commonly lost or concealed. Both Camptocrinus and Neocamptocrinus have three small anals in the base of the tegmen immediately above the large single primanal in the radial circlet. The column tapered to a distal point in both genera and was anchored to the substrate by a radicular runner. It may be that the two genera are one, but, if not, Neocamptocrinus is strictly Permian and limited to Tethys.

Debbie I.E. Schoor [[email protected]], Perobahout 2, 2719 KR Zoetermeer, the Netherlands; Stephen K. Donovan* [[email protected]], Naturalis Biodiversity Center, Postbus 9517, 2300 RA Leiden, the Netherlands; Gary D. Webster [[email protected]], School of Earth and Environmental Sciences, Washington State University, Pullman, WA 99164-2812, USA

Key words:

• Platycrinitidae
• Camptocrinidae
• Artinskian
• systematics.

Acknowledgements

Debbie Schoor thanks Naturalis Biodiversity Center, Leiden, for giving her the opportunity to work on this project as part of her M.Sc. training. Gary Webster extends his appreciation to Washington State University for granting sabbatical leaves in 1989 and 1998 for the study, respectively, of the Permian crinoids of Western Australia and the study of West Timor crinoid collections, the latter at the Netherlands Centre for Biodiversity Naturalis in Leiden, supported by a Temminck Fellowship. Incisive review comments by Professor James R. Thomka (State University of New York at Plattsburgh) and two anonymous referees are gratefully acknowledged.

Disclosure statement

No potential conflict of interest was reported by the authors.