The remedial conservation and support jacketing of the Massospondylus carinatus neotype
Date
2018-03
Authors
Graham, Mark R.
Choiniere, Jonah N.
Jirah, Sifelani
Barrett, Paul M.
Journal Title
Journal ISSN
Volume Title
Publisher
Evolutionary Studies Institute
Abstract
Massopondylus carinatus Owen, 1854 is a non-sauropodan
sauropodomorph (‘prosauropod’) dinosaur whose
remains are abundant in the Upper Karoo Supergroup
sediments of southern Africa (e.g. Owen 1854; Seeley
1895; Cooper 1981; Gow 1990; Gow et al. 1990; Sues et al.
2004; Barrett & Yates 2006; Reisz et al. 2005). It occurs at
numerous localities in the Upper Elliot and Clarens
formations of South Africa and Lesotho, as well as in the
Forest Sandstone Formation of Zimbabwe (Haughton
1924; Cooper 1981; Kitching&Raath 1984). Several almost
complete skeletons are known, including skulls, and as a
result Massospondylus has featured heavily in discussions
of early dinosaur ecology, phylogeny and palaeobiology
(e.g. Cooper 1981; Barrett 2000; Zelenitsky & Modesto
2002; Reisz et al. 2005, 2012; Apaldetti et al. 2011, among
many others). However, the original syntype series of
Massospondylus carinatus was destroyed duringWorldWar
II and shown to be taxonomically indeterminate, undermining
the nomenclatural stability of this important taxon
(Sues et al. 2004; Yates & Barrett 2010).
In order to rectify this problem, a complete skeleton
representing an adult individual, BP/1/4934 (nicknamed
‘Big Momma’), was designated as the neotype (Yates &
Barrett 2010). BP/1/4934 was collected from the Upper Elliot Formation of Bormansdrift Farm, in the Clocholan
District of the Free State, by Lucas Huma and James
Kitching in 1980 (see Kitching & Raath 1984, for locality
details). This farm is also the type locality of the early turtle
Australochelys (Gaffney and Kitching, 1994) and has
yielded other Upper Elliot formation tetrapod material
including the cynodont Pachygenelus and other sauropodomorph
remains (Kitching&Raath 1984). BP/1/4934 is
the most complete specimen of a non-sauropodan
sauropodomorph dinosaur known from the entire African
continent and is therefore of major regional and international
significance. In addition, since 1990 it has formed
part of a permanent public exhibit showcasing African
palaeontological discoveries in the J. W. Kitching Gallery
of the Evolutionary Studies Institute (ESI) of the University
of the Witwatersrand.
During recent research work on BP/1/4934, as part of an
on-going collaboration on early dinosaurs between the
ESI and Natural History Museum, London (NHMUK), it
was noted that its condition had deteriorated and that
urgent remedial conservation work was required in order
to preserve it for future generations. As a result, the specimen
was temporarily removed from public display to
facilitate this work, which is described in detail below (see
also Graham 2017). The primary purpose of the conservation
project was to assess the condition of the specimen,
undertake conservation in order to stabilise it and to
manufacture ‘clam-shell’ type support mounts/jackets for
each of the blocks to enable the specimen to be displayed
in an articulated posture within a purpose-built display
case. An important consideration was that the blocks
should be readily accessible from both left and right sides
to researchers whilst securing the fossil safely. Finally, this
project also provided an opportunity to facilitate knowledge
exchange between the conservation staff at the ESI
and NHMUK, in order to share and extend technical
expertise.