Araucarioxylon Kraus is a widely known fossil-genus generally applied to woods similar to that of the extant Araucariaceae. However, since 1905, several researchers have pointed out that this name is an illegitimate junior nomenclatural synonym. At least four generic names are in current use for fossil wood of this type: Agathoxylon Hartig, Araucarioxylon, Dadoxylon Endl. and Dammaroxylon J.Schultze-Motel. This problem of inconsistent nomenclatural application is compounded by the fact that woods of this type represent a wide range of plants including basal pteridosperms, cordaitaleans, glossopterids, primitive conifers, and araucarian conifers, with a fossil record that extends from the Devonian to Holocene. Conservation of Araucarioxylon has been repeatedly suggested but never officially proposed. Since general use is a strong argument for conservation, a poll was conducted amongst fossil wood anatomists in order to canvass current and preferred usage. It was found that the community is divided, with about one-fifth recommending retention of the well-known Araucarioxylon, whereas the majority of others advocated use of the legitimate Agathoxylon. The arguments of the various colleagues who answered the poll are synthesized and discussed. There is clearly little support for conservation of Araucarioxylon. A secondary aspect of the poll tackled the issue as to whether Araucaria-like fossil woods should be either gathered into a unique fossil-genus, or whether two fossil-genera should be recognized, based on the respective presence or absence of axial parenchyma. A majority of colleagues favoured having one fossil-genus only. Agathoxylon can be used legitimately and appears to be the most appropriate name for such woods. However, its original diagnosis must be expanded if those woods lacking axial parenchyma are to be included.

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The gigantopterids are a pan-palaeotropical Late Palaeozoic (to Early Mesozoic) plant group with unknown affiliations. Two gigantopterid species, both sole representatives of their respective genera, are known from the Early Permian Mengkarang Formation of Jambi (Sumatra, Indonesia). Through an emendation of the Jambi gigantopterids, based on the old and newly collected material, and a subsequent analysis of the leaf morphology of several gigantopterid genera, we conclude that the Jambi species are similar to the other gigantopterids, but do not appear to be related to them directly. We propose a possible scenario for the evolution of gigantopterid leaf morphology, based on marginal leaf growth, with implications for the validity of the gigantopterids as a natural group.

The Merangin River section in Sumatra exposes the Permian Mengkarang Formation. This is composed of eight intervals showing upwards fining and thinning of volcanic tuffs and volcaniclastic sedimentary rocks, overlain by their reworked alluvial products. Isotopic age evaluation of the top and the base of the Merangin section indicates an average duration of 630,000 years (from 296.77 ± 0.04 to 296.14 ± 0.09 Ma). Extrapolation of the eight intervals onto neighbouring tributaries by using earlier geological studies and the strike of the beds allows for the integration of the data assembled in recent expeditions, and those from 1925, leading to the lithostratigraphic assignment of more than 2,000 palaeobotanical specimens. The compilation of all assembled palaeobotanical data indicates there is a change in composition from a palaeoflora dominated by Cordaites, ferns, or club mosses to one in which seed ferns were dominant. These changes, coupled to eustatic sea‐level fluctuations, indicate a climatic origin for this transition and extend palaeofloral trends perceived earlier in Far Western low latitudes to the Far Eastern Palaeotethys.