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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Com base na bibliografia e na revisão taxonômica de lenhos fósseis do Eopermiano da Bacia do Paraná, Brasil, três novas combinações, Myelontordoxy lon camposii (Mussa), Abietopitys  articulata (Dohms) e Paulistoxylon iratiensis (Guerra-Sommer), são propostas e uma espécie, Polysolenoxylon bortoluzzii Guerra, é considerada inválida. Excetuando-se M. camposii, originária da Formação Irati no Estado de São Paulo, todas as demais são provenientes da Formação Serra Alta no Estado do Rio Grande do Sul. Com base nas novas combinações, apresentam-se emendas à diagnose genérica de Myelontordoxylon Mussa e à diagnose específica de A. articulata (Dohms).

A taxonomia dos lenhos permianos da bacia do Paraná remonta ao final do século XIX e inaugura com a descrição de Dadoxylon pedroi, identificado por Zeiller (1895) nas camadas de carvão da Formação Rio Bonito expostas no Vale do Jaguarão, no estado do Rio Grande do Sul. Entretanto, somente a partir de meados do século XX este tipo de pesquisa ganhou impulso, com as revisões e identificações feitas por Kräusel e Dolianiti (1958) e