British Wenlock crinoids at the Western Australian Museum

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1 ISSN X (Print) ISSN (Online) British Wenlock crinoids at the Western Australian Museum Stephen K. Donovan 1 DONOVAN, S.K. (2012). British Wenlock crinoids at the Western Australian Museum. Proceedings of the Shropshire Geological Society, 17, A display of Silurian fossil corals, trilobites and crinoids in the Western Australian Museum, Perth, is comprised of specimens from the Much Wenlock Limestone Formation. These formed a part of the collection of James Tennant ( ), a London mineral, fossil and shell dealer. Despite what is stated on the display label, most, if not all, specimens are likely to come from Dudley, not Shropshire. Most of the crinoids are referred to species described by John Phillips in Department of Geology, NCB Naturalis, Postbus 9517, 2300 RA Leiden, The Netherlands. Steve.Donovan@ncbnaturalis.nl INTRODUCTION Travelling long distances and accidentally bumping into old friends is one of life s pleasures. I had never visited Australia until late July 2012, and was looking forward to a few days mixing business with pleasure. Thus it was that I found myself in the geology gallery, Dinosaurs to diamonds, of the Western Australian Museum (WAM) in Perth by lunchtime on my first day. Despite the fine displays of dinosaurs, rocks and minerals, and fossil marsupials, it was a glass cabinet of Lower Palaeozoic fossils that caught my eye. TENNANT S WENLOCK CRINOIDS Labelled Life in a Shallow Sea 430 million years ago, this cabinet covered the common groups of Lower Palaeozoic invertebrates. The centrepiece is a slab about 1.3 m long displaying some fine trilobites from China. Smaller slabs of grey and (mainly) pink mudrocks from Australia bear well-preserved graptolites. Three more trilobites were Australian in origin. And all other specimens on display in this cabinet were from the Much Wenlock Limestone Formation of Shropshire and Dudley. This should not, perhaps, have surprised me. In the 19 th Century collections of well-preserved Wenlock fossils from Dudley were sold to many museums around the world. For example, there are collections that I have worked on in the National Museum of Natural History, Smithsonian Institution, Washington, D.C., and my home institution, Naturalis in Leiden. What was unexpected was that they should form a prominent part of the display rather than be limited to the research collections. The display includes two slabs of Much Wenlock Limestone Formation, each of about 200 x 200 mm, bearing typical components of the Wenlock benthos such as brachiopods, bryozoans, trilobite fragments and crinoids (Figure 1A). An explanatory label states that Specimens displayed here come from W.A. Museum s Tennant Collection, and probably represent some of the earliest of these fossils collected in the early 19 th century. James Tennant ( ) was a dealer in minerals, fossils and shells whose shop was in London (Wilson, 2012); he was a fellow of the Geological Society and, in , president of the Geologists Association. The WAM s Tennant Collection consists of specimens sent to Western Australia by the British Museum (Natural History) (Groves, 2010). Groups from the Wenlock that are highlighted in this display include corals, trilobites and crinoids. Rugose corals include Omphyma turbinatum Haime, Omphyma subturbinatum (d Orbigny), Kodonophyllum truncatum (Linné) and Acervularia luxurians Eichwald. These are complemented by the tabulate corals Syringopora bifurcata Lonsdale, Favosites forbesi Milne-Edwards & Haime and Halysites catenularius (Linné) (Figure 1B-E). The trilobites include Calymene blumenbachi Brongiart, Encrinurus punctatus (Wahlenberg), Acidaspis brightii Murchison and Bumastus barriensis Murchison (Figure 1F-H). But of particular interest to me were the crinoids, which, recently, have been mono- Proceedings of the Shropshire Geological Society, 17, Shropshire Geological Society

2 BRITISH WENLOCK CRINOIDS Figure 1. Silurian fossils of the Much Wenlock Limestone Formation on display in the Western Australian Museum, Perth. (A) Block of Wenlock Limestone containing trilobites, brachiopods, bryozoans and crinoids (specimen label). Block c. 200 mm wide. (B, C) Solitary rugose corals. (B) Omphyma turbinatum Haime. (C) Omphyma subturbinatum (d Orbigny). (D, E) Tabulate corals. (D) Favosites forbesi Milne-Edwards & Haime, polished section. (E) Syringopora bifurcata Lonsdale. (F-H) Trilobites. (F, H) Calymene blumenbachi Brongiart. (F) Enrolled. (H) Dorsal view. (G) Bumastus barriensis Murchison, dorsal view.. -graphed as part of a study of the larger British Silurian echinoderm fauna (Lewis et al., 2007; Donovan et al., 2008, 2009, 2010, 2012). Despite the display label stating One of the classic localities for fossils of this age is the Wenlock Limestone of Shropshire, England, there is little doubt that the well-preserved trilobites and crinoids, at least, are from Dudley rather than Wenlock Edge. Currently there are about 60 nominal species of crinoid known from the Much Wenlock Limestone Formation. There are five species on display in the WAM, that is, about 8% of the specific diversity; as each belongs to a different genus, this is about a seventh of the 35 genera known from Dudley (Donovan et al., 2012, table 8). Of the three major crinoid groups in the Silurian of the British Isles, the disparids are not represented. However, these are typically small and not really well suited to public display; interestingly, none were recognised in the earliest monograph on the British Silurian Proceedings of the Shropshire Geological Society, 17, Shropshire Geological Society

3 S.K. DONOVAN Figure 2. Silurian crinoids of the Much Wenlock Limestone Formation on display in the Western Australian Museum, Perth. (A, E) The monobathrid camerate Periechocrinus costatus (Austin & Austin). (B) The cyathocrinid cladid Cyathocrinites monile Salter. (C) The diplobathrid camerate Dimerocrinites decadactylus Phillips. (D) The flexible cladid Sagenocrinites expansus (Phillips). (F) The cyathocrinid cladid Gissocrinus goniodactylus (Phillips). crinoids (Phillips, 1839). Cladids include the cyathocrinids Cyathocrinites monile Salter (labelled as the junior synonym C. actinotubus Angelin) and Gissocrinus goniodactylus (Phillips), and the flexible Sagenocrinites expansus (Phillips) (Figure 2B, D, F). Camerates are the diplobathrid Dimerocrinites decadactylus Phillips and the monobathrid Periechocrinus costatus (Austin & Austin) (labelled as Periechocrinites moniliformis; for a Proceedings of the Shropshire Geological Society, 17, Shropshire Geological Society

4 BRITISH WENLOCK CRINOIDS full discussion of the invalidity of this name, see Donovan & Riley, 2011; Donovan et al., 2012); one specimen is mislabelled Eucalyptocrinites decorus (Phillips) (Figures 2A, C, E). Above I compared the diversity of the crinoids in this display with what we know of the crinoids of the Much Wenlock Limestone Formation at the present day. However, this was perhaps the wrong assessment to make. Rather, how do these five species relate to those known at the time of the death of James Tennant in 1881? The only monograph of the British Silurian crinoids was Phillips (1839). Before 1881, the most important taxonomic additions were by Salter (1873) and Angelin (1878), the latter including some taxa common to both Gotland and Dudley. Phillips described fourteen species (Donovan, 2009), to which Salter added 20 and Angelin six taxa (Donovan et al., 2009, 2010, 2012). Not all of Salter s species had been adequately illustrated (if at all) by 1881, but, nevertheless, about 40 species were recognised in total, that is, about two thirds of those known at the present day. But of the five species displayed in the WAM, four are either Phillips species, or, in the example of Periechocrinus costatus, was renamed soon after 1839 (Austin & Austin, 1843). Phillips s species were the first to be described and named, including just three after Miller (1821; see Donovan, 2009), and might be considered the commonest taxa. The make-up of Tennant s collection seems to support this; none of the displayed species are referable to later species. ACKNOWLEDGEMENTS My trip to Perth was supported by Curtin University of Technology, Bently, which I gratefully acknowledge. The Western Australian Museum, Perth, is congratulated for having such a stimulating palaeontological display. REFERENCES Angelin, N.P. (1878). Iconographia crinoideorum in Stratis Sueciae Siluricus fossilium. Holmiae, iv+62 pp. Austin, T., & Austin, T., Jr. (1843). Description of several new genera and species of Crinoidea. Annals and Magazine of Natural History (series 1), 11, Donovan, S.K. (2009). John Phillips and the British Silurian Crinoidea: 170 years of monographic endeavour. Proceedings of the Yorkshire Geological Society, 57, Donovan, S.K., Lewis, D.N., Crabb, P. & Widdison, R.E. (2008). A field guide to the Silurian Echinodermata of the British Isles: Part 2 - Crinoidea, minor groups and discussion. Proceedings of the Yorkshire Geological Society, 57, Donovan, S.K., Lewis, D.N., Fearnhead, F.E. & Widdison, R.E. (2009). The British Silurian Crinoidea. Part 1, introduction and Disparida. Monographs of the Palaeontographical Society, London, 163 (632), Donovan, S.K. & Riley, M. (2011). What's in a (wrong) name? Thoughts on the true utility of electronic museum catalogues. The Geological Curator, 9, Donovan, S.K., Widdison, R.E., Lewis, D.N. & Fearnhead, F.E. (2010). The British Silurian Crinoidea. Part 2, addendum to Part 1 and Cladida. Monograph of the Palaeontographical Society, London, 164 (635), Donovan, S.K., Widdison, R.E., Lewis, D.N. & Fearnhead, F.E. (2012, in press). The British Silurian Crinoidea. Part 3, addendum to parts 1 and 2, Camerata and columnals. Monograph of the Palaeontographical Society, London, 166. Groves, W. (2010). Geobabble. Black Country Geological Society Newsletter, 203, p. 14. Lewis, D.N., Donovan, S.K., Crabb, P. & Gladwell, D.J. (2007). A field guide to the Silurian Echinodermata of the British Isles: Part 1 - Eleutherozoa and Rhombifera. Scripta Geologica, 134, Miller, J.S. (1821). A natural history of the Crinoidea or lily-shaped animals, with observations on the genera Asteria, Eurayle, Comatula and Marsupites. C. Frost, Bristol, 150 pp. Phillips, J. (1839). Organic remains. In: The Silurian System, part 2 (R.I. Murchison), pp John Murray, London. Salter, J.W. (1873). A catalogue of the collection of Cambrian and Silurian fossils contained in the Geological Museum of the University of Cambridge. Cambridge University Press, Cambridge, xlviii+204 pp. Proceedings of the Shropshire Geological Society, 17, Shropshire Geological Society

5 Wilson, W.E. (2012). James Tennant ( ). Mineralogical Record Biographical Archive, 3 pp. Accessed 11 September S.K. DONOVAN Copyright Shropshire Geological Society ISSN x Proceedings of the Shropshire Geological Society, 17, Shropshire Geological Society