Elatra: A glossopterid fructification with a bipartite, hooded wing from the lower Permian of Madagascar and South Africa

First discovered nearly 100 years ago, Hirsutum leslii (Thomas 1921) Smithies ex. Anderson et Anderson 1985 is one of the largest and most striking ovuliferous glossopterid fructifications known from Gondwana. A detailed examination of the extensive collection of impression/compression fossils from the lower Permian Hammanskraal locality in South Africa has revealed the presence of a peculiar and elaborate wing structure in this seed-bearing organ that was largely unrecognised in previous studies. Hirsutum leslii is assigned to Elatra leslii (Thomas 1921) comb. nov. in recognition of the unusual wing morphology shared only by the very similar Madagascan taxon Elatra bella Appert 1977, and in light of the disassembly of Hirsutum and transferral of the type species H. dutoitides (Plumstead 1952) Plumstead 1958 to Gladiopomum (Plumstead 1952) Adendorff et al. 2002. Preparation of the interleaved layers of matrix and impression/compression fossils revealed that the hooded wing of the fructification represents a modification of the double-wing structure evident in Bifariala intermittens (Plumstead 1952) Prevec et al. 2008. As in Bifariala, two superposed wings are present - an acuminate wing with campylodromous venation that is confluent with the veined surface of the fructification, and a radially striate wing that is contiguous with the seed-bearing surface of the receptacle. However, the radially striated wing in Elatra is over-arched into a hood-like feature that partially encloses the seed-bearing surface. The medial to basal portion of this cowled wing is more typical of other winged members of the Dictyopteridiaceae, such as Scutum, and forms a lobe to either side of, or overlaps the pedicel. The fructification is attached to the petiole of a Glossopteris leaf, with the seed-bearing surface of the receptacle oriented towards the subtending leaf. The base of the attached leaf is laterally expanded. This cloistered architecture, consistently evident in apparently mature dispersed fructifications, raises questions as to the pollination mechanism employed by these plants.