An extinct group of mostly Gondwanan snakes with fossil history extending from early Cenomanian (early upper Cretaceous) to late Pleistocene. Classified as a 'subfamily' of Boidae and then a distinct 'Family' in Linnean systems, otherwise as a likely clade within Serpentes, or possible paraphyletic stem-group outside Serpentes and within a more inclusive Ophidia. Families Acrochordidae Aniliidae Anomalepididae Anomochilidae Atractaspididae Boidae Bolyeriidae Colubridae Cylindrophiidae Elapidae Hydrophiidae Leptotyphlopidae Loxocemidae Pythonidae Tropidophiidae Typhlopidae Uropeltidae Viperidae Xenopeltidae Snakes are cold blooded legless reptiles closely related to lizards, which share the order Squamata. ... For other uses, see Boa (disambiguation). ...

Like most fossil snakes the majority of madtsoiids are known only from isolated vertebrae, but several (Madtsoia bai, M. camposi, Wonambi naracoortensis, Nanowana spp., unnamed Yurlunggur spp., Najash rionegrina) have associated or articulated parts of skeletons. Of the included taxa listed below, all have been referred to Madtsoiidae in all recent classifications except Najash rionegrina, which is included based on diagnostic vertebral characters described by Apesteguía and Zaher (2006).

Rieppel et al. (2002) classified Wonambi naracoortensis within the extant radiation (crown group) of snakes as Macrostomata incertae sedis, but many of their character state attributions for this species have been criticised or refuted by Scanlon (2005a) and the better-preserved skulls of Yurlunggur sp./spp. have numerous characters apparently more plesiomorphic than any macrostomatans (Scanlon 2006). The partial skull attributed to Najash rionegrina (Apesteguía and Zaher 2006) resembles that of the non-madtsoiid Dinilysia patagonica, raising the possibility of misassociation. The type material of Najash is the only madtsoiid specimen retaining evidence of pelvic and hindlimb elements, which are claimed to be more plesiomorphic than other Cretaceous limbed snakes (Pachyrhachis, Haasiophis, Eupodophis) in retaining a sacro-iliac contact. The latter condition is perhaps misleadingly described by Apesteguía and Zaher as unique possession of a sacrum, whereas it has rarely been questioned that the cloacal vertebrae in snakes are homologous to the sacrals of limbed squamates (i.e. the sacrum is present but has lost contact with the reduced ilia in other taxa). It would be unsurprising if other madtsoiids also possessed hindlimbs as complete as those of Najash.

Madtsoiids range in size from less than 1 m (estimated total length) to over 9 m, and are thought to have been constrictors analogous to modern pythons and boas, but with more primitive jaw structures less highly adapted for swallowing large prey.

Several madtsoiid genera have been named using indigenous words for legendary Rainbow Serpents or dragons, including Wonambi (Pitjantjatjara language), Yurlunggur (Yolngu) and Nanowana (Greek nano-, 'dwarf' + Warlpiri Wana) in Australia, and Herensugea (Basque) in Europe. G.G. Simpson (1933) apparently started this trend by compounding Madtsoia from indigenous (Tehuelche) roots, although the reference was geographic rather than mythological (mad, 'valley' + tsoi, 'cow' as a translation of the type locality Cañadón Vaca).

Madtsoiidae Hoffstetter, 1961a (as Madtsoiinae < Boidae)

Diagnosis: Snakes of small to very large size; hypapophyses present only in anterior trunk; middle and posterior trunk vertebrae with moderately or well developed haemal keel (except a few near the cloacal region), often with short laterally paired projections on the posterior part of the keel. All trunk and caudal vertebrae with a parazygantral foramen (or sometimes several foramina) in a more or less distinct fossa lateral to each zygantral facet; prezygapophyseal processes absent; paracotylar foramina present; diapophyses relatively wide, exceeding width across prezygapophyses at least in posterior trunk vertebrae. (Scanlon 2005)

Included taxa:

Gigantophis Andrews, 1901

 Gigantophis_garstini Andrews, 1901 (Andrews 1906, Hoffstetter 1961b; Paleogene, Late Eocene; Egypt, Libya) 

Madtsoia Simpson, 1933 There are very few or no other articles that link to this one. ...

 Madtsoia bai Simpson, 1933 (Paleogene, Early Eocene; Argentina) Madtsoia cf. M. bai (Simpson 1935, Hoffstetter 1960; Paleogene, Late Paleocene; Argentina) Madtsoia madagascariensis Hoffstetter, 1961a (Piveteau 1933; Cretaceous, Santonian or Campanian; Madagascar) Madtsoia aff. madagascariensis (de Broin et al. 1974; Cretaceous, Coniacian or Santonian, Niger) Madtsoia laurasiae Rage, 1996 (Astibia et al. 1990; Cretaceous, Campanian or Maastrichtian; Spain) Madtsoia camposi Rage, 1998 (Paleogene, middle Paleocene; Brazil) 

Wonambi Smith, 1976

 Wonambi naracoortensis Smith, 1976 (Scanlon and Lee 2000, Scanlon 2005; Neogene, Pliocene to Pleistocene; Australia) Wonambi barriei Scanlon in Scanlon and Lee, 2000 (Neogene, early Miocene; Australia) 

Patagoniophis Albino, 1986

 Patagoniophis parvus Albino, 1986 (Cretaceous, Campanian or Maastrichtian; Argentina) Patagoniophis australiensis Scanlon, 2005 (Scanlon 1993; Paleogene, early Eocene; Australia) 

Alamitophis Albino, 1986

 Alamitophis argentinus Albino, 1986 (Cretaceous, Campanian or Maastrichtian; Argentina) Alamitophis elongatus Albino, 1994 (Cretaceous, Campanian or Maastrichtian; Argentina) Alamitophis tingamarra Scanlon, 2005 (Scanlon 1993; Paleogene, early Eocene; Australia) 

Rionegrophis Albino, 1986

 Rionegrophis madtsoioides Albino, 1986 (Cretaceous, Campanian or Maastrichtian; Argentina) 

Yurlunggur Scanlon, 1992

 Yurlunggur camfieldensis Scanlon, 1992 (Neogene, middle Miocene; Australia) Yurlunggur spp. (Scanlon 2004, 2006; Paleogene-Neogene, late Oligocene to late Pleistocene; Australia) 

Herensugea Rage, 1996

 Herensugea caristiorum Rage, 1996 (Cretaceous, Campanian or Maastrichtian; Spain) 

Nanowana Scanlon, 1997

 Nanowana godthelpi Scanlon, 1997 (Neogene, early to middle Miocene; Australia) Nanowana schrenki Scanlon, 1997 (Neogene, early to middle Miocene; Australia) 

Najash Apesteguía and Zaher, 2006

 Najash rionegrina Apesteguía and Zaher, 2006 (Cretaceous, Cenomanian; Argentina) 

Unnamed

 Madtsoiidae indet. (Rage 1987; Paleogene, Paleocene; Morocco) Madtsoiidae indet. (Werner and Rage 1994, Rage and Werner 1999; Cretaceous, Cenomanian; Sudan) ?Madtsoiid (Rage and Prasad 1992; Cretaceous, Maastrichtian; India) ?Madtsoiid (Rage 1991; Paleogene, early Paleocene; Bolivia) ?Madtsoiidae indet. cf. Madtsoia sp. (Scanlon 2005; Paleogene, early Eocene; Australia) Madtsoiidae indet. (Folie and Codrea 2005; Cretaceous, Maastrichtian; Romania) Madtsoiidae nov. (Gomez and Baez 2006; Cretaceous, late Campanian or early Maastrichtian; Argentina) 

Phylogeny (Scanlon 2006)

 -----+-------Pachyrhachis† | +----+-----Haasiophis† | +---+--------+----Wonambi† | | | +----Yurlunggur† | +---+-----Dinilysia† | +---+-----Scolecophidia | +-----Alethinophidia 

References

Albino, A.M. 1986. Nuevos Boidae Madtsoiinae en el Cretacico tardio de Patagonia (Formacion Los Alamitos, Rio Negro, Argentina). Pp. 15-21 in J.F. Bonaparte (ed.), Simposio Evolucion de los Vertebrados Mesozoicos. Actas IV Congreso Argentino de Paleontología y Bioestratigrafía, Mendoza.

Albino, A.M. 1994. Una nueva serpiente (Reptilia) del Cretácico Superior de Patagonia, Argentina. Pesquisas 21: 58-63.

Andrews, C.W. 1901. Preliminary note on some recently discovered extinct vertebrates from Egypt (Part II). Geological Magazine 8: 434-444.

Andrews, C.W. 1906. A descriptive catalogue of the Tertiary Vertebrata of the Fayum, Egypt. British Museum (Natural History), London.

Apesteguía, S. and H. Zaher. 2006. A Cretaceous terrestrial snake with robust hindlimbs and a sacrum. Nature 440: 1037-1040.

Astibia, H., E. Buffetaut, A.D. Buscalioni, H. Cappetta, C. Corral, R. Estes, F. Garcia-Garmilla, J.J. Jaeger, E. Jimenez-Fuentes, J. Le Loeuff, J.M. Mazin, X. Orue-Extebarria, J. Pereda-Suberbiola, J.E. Powell, J.-C. Rage, J. Rodriguez-Lazaro, J.L. Sanz, and H. Tong. 1991. The fossil vertebrates from Laño (Basque Country, Spain); new evidence on the composition and affinities of the Late Cretaceous continental faunas of Europe. Terra Nova 2: 460-466.

de Broin, F., E. Buffetaut, J.C. Koeniguer, J.-C. Rage, P. Taquet, C. Vergnaud-Grazzini, and S. Wenz. 1974. La faune de Vertébrés continentaux du gisement d'In Beceten (Sénonien du Niger). Comptes rendus de l'Académie des Sciences, Paris 279: 469-472.

Folie, A. and V. Coria. 2005. New lissamphibians and squamates from the Maastrichtian of Hateg Basin, Romania. Acta Palaeontologica Polonica 50: 57-71.

Gomez, R.O. and A.M. Baez. 2006. A new madtsoiid snake (Squamata, Ophidia) from the Upper Cretaceous of Patagonia. XXII Jornadas Argentinas de Paleontología de Vertebrados, San Juan, Argentina (2006): 21.

Hoffstetter, R. 1960. Un dentaire de Madtsoia (serpent géant du Paléocene de Patagonia). Bulletin du Muséum national d'Histoire naturelle, Paris (2) 31: 379-386.

Hoffstetter, R. 1961a. Nouveaux restes d'un serpent boïdé (Madtsoia madagascariensis nov. sp.) dans le Crétacé supérieur de Madagascar. Bulletin du Muséum national d'Histoire naturelle, Paris (2) 33: 152-160.

Hoffstetter, R. 1961b. Nouvelles recoltes de serpents fossiles dans l'Eocene superieure de desert libyque. Bulletin du Muséum national d'Histoire naturelle, Paris (2) 33: 326-331.

Rage, J.-C. 1991. Squamate reptiles from the early Paleocene of the Tiupampa area (Santa Lucia Formation), Bolivia. Pp. 503-508 in R. Suarez-Soruco (ed.), Fosiles y Facies de Bolivia. Revista Tecnica de Yacimentos Petroliferos Fiscales Bolivianos 12: 503-508.

Rage, J.-C. 1996. Les Madtsoiidae (Reptilia, Serpentes) du Crétacé supérieur d’Europe: témoins gondwaniens d’une dispersion transtéthysienne. Comptes Rendus de l’Académie des Sciences, Paris, Série 2, 322: 603-608.

Rage, J.-C. 1998. Fossil snakes from the Paleocene of São José de Itaboraí, Brazil. Part I. Madtsoiidae, Aniliidae. Palaeovertebrata 27(3-4): 109-144.

Rage, J.-C., and G.V.R. Prasad. 1992. New snakes from the late Cretaceous (Maastrichtian) of Naskal, India. Neues Jahrbuch für Geologie und Paläontologie Abhandlungen 187: 83-97.

Rage, J.-C., and C. Werner. 1999. Mid-Cretaceous (Cenomanian) snakes from Wadi Abu Hashim, Sudan: The earliest snake assemblage. Palaeontologia Africana 35: 85-110.

Rieppel, O., A.G. Kluge, and H. Zaher. 2002. Testing the phylogenetic relationships of the Pleistocene snake Wonambi naracoortensis Smith. Journal of Vertebrate Paleontology 22: 812-829.

Scanlon, J.D. 1992. A new large madtsoiid snake from the Miocene of the Northern Territory. The Beagle, Records of the Northern Territory Museum of Arts and Sciences 9: 49-60.

Scanlon, J.D. 1993. Madtsoiid snakes from the Eocene Tingamarra Fauna of eastern Queensland. Kaupia: Darmstädter Beiträge zur Naturgeschichte 3: 3-8.

Scanlon, J.D. 1997. Nanowana gen. nov., small madtsoiid snakes from the Miocene of Riversleigh: sympatric species with divergently specialised dentition. Memoirs of the Queensland Museum 41: 393-412.

Scanlon, J.D. 2003. The basicranial morphology of madtsoiid snakes (Squamata, Ophidia) and the earliest Alethinophidia (Serpentes). Journal of Vertebrate Paleontology 23(4): 971-976.

Scanlon, J.D. 2004. First known axis vertebra of a madtsoiid snake (Yurlunggur camfieldensis) and remarks on the neck of snakes. The Beagle: Records of the Museums and Art Galleries of the Northern Territory 20: 207-215.

Scanlon, J.D. 2005. Cranial morphology of the Plio-Pleistocene giant madtsoiid snake Wonambi naracoortensis. Acta Palaeontologica Polonica 50: 139-180.

Scanlon, J.D. 2005. Australia’s oldest known snakes: Patagoniophis, Alamitophis, and cf. Madtsoia (Squamata: Madtsoiidae) from the Eocene of Queensland. Memoirs of the Queensland Museum 51: 215-235.

Scanlon, J.D. 2006. Skull of the large non-macrostomatan snake Yurlunggur from the Australian Oligo-Miocene. Nature 439: 839-842.

Scanlon, J.D., and M.S.Y. Lee. 2000. The Pleistocene serpent Wonambi and the early evolution of snakes. Nature 403: 416-420.

Simpson, G.G. 1933. A new fossil snake from the Notostylops beds of Patagonia. Bulletin of the American Museum of Natural History 67: 1-22.

Simpson, G.G. 1935. Early and middle Tertiary Geology of the Gaiman region, Chubut, Argentina. American Museum Novitates (775): 1-29.

Smith, M.J. 1976. Small fossil vertebrates from Victoria Cave, Naracoorte, South Australia. IV. Reptiles. Transactions of the Royal Society of South Australia 100: 39-51.

Werner, C., and J.-C. Rage. 1994. Mid-Cretaceous snakes from Sudan. A preliminary report on an unexpectedly diverse snake fauna. Comptes Rendus de l'Académie des Sciences, Paris, Série 2, 319: 247-252.