Recumbirostra was erected as a clade in 2007 to include many of the taxa traditionally grouped in "Microsauria", which has since been shown to be aparaphyletic orpolyphyletic grouping.[7][8][9] Like other "microsaurs", the recumbirostrans have traditionally been considered to be members of the subclassLepospondyli; however, many phylogenetic analyses conducted since the 2010s have recovered recumbirostrans as basalsauropsid (reptilian)amniotes instead.[10][7][5][3][11] However, the placement of recumbirostrans as reptiles has been challenged by other authors, who have recovered them asstem-amniotes instead, and contended that the shared characters between recumbirostrans and reptiles are convergent,[12] or the result of incorrect character encoding.[13] Not allphylogenetic analyses recognize Recumbirostra as a valid grouping. An alternative clade calledTuditanomorpha is occasionally supported and includes many of the same taxa.[14] Furthermore, the taxa that are often considered to be recumbirostrans have been found among amphibians (and not as a distinct clade) in some analyses.[15]
^abGlienke, S. (2012). "A new "microsaur" (Amphibia; Lepospondyli) from the Rotliegend of the Saar–Palatinate region (Carboniferous/Permian transition; West Germany)".Paläontologische Zeitschrift.86 (3):297–311.Bibcode:2012PalZ...86..297G.doi:10.1007/s12542-012-0130-8.S2CID140699792.
^abMann, A.; Pardo, J. D.; Maddin, H. C. (2019). "Infernovenator steenae, a new serpentine recumbirostran from the 'Mazon Creek' Lagerstätte further clarifies lysorophian origins".Zoological Journal of the Linnean Society.187 (2):506–517.doi:10.1093/zoolinnean/zlz026.
^Anderson, J.S. (2007). "Incorporating ontogeny into the matrix: A phylogenetic evaluation of developmental evidence for the origin of modern Amphibians". In Anderson, J.S.; Sues, H.-D. (eds.).Major Transitions in Vertebrate Evolution. Bloomington and Indianapolis: Indiana University Press. pp. 182–227.
^Huttenlocker, A. K.; Pardo, J. D.; Small, B. J.; Anderson, J. S. (2013). "Cranial morphology of recumbirostrans (Lepospondyli) from the Permian of Kansas and Nebraska, and early morphological evolution inferred by micro-computed tomography". Journal of Vertebrate Paleontology 33 (3): 540.
^Jason D. Pardo, Matt Szostakiwskyj and Jason S. Anderson (2015). "Phylogenetic relationships of recumbirostran 'lepospondyls' inferred from neurocranial morphology".Society of Vertebrate Paleontology 75th Annual Meeting Program & Abstracts: 191.
^Jenkins, Xavier A.; Sues, Hans‐Dieter; Webb, Savannah; Schepis, Zackary; Peecook, Brandon R.; Mann, Arjan (2025-01-07). "The recumbirostranHapsidopareion lepton from the early Permian (Cisuralian: Artinskian) of Oklahoma reassessed using HRμCT, and the placement of Recumbirostra on the amniote stem".Papers in Palaeontology.11 (1).doi:10.1002/spp2.1610.ISSN2056-2799.
