Albanerpetontidae

The Albanerpetontidae (also spelled Albanerpetidae and Albanerpetonidae) are an extinct family of small amphibians, native to the Northern Hemisphere during the Mesozoic and Cenozoic. The only members of the order Allocaudata, they are thought to be allied with living amphibians belonging to Lissamphibia. Despite a superficially salamander-like bodyform, their anatomy is strongly divergent from modern amphibians in numerous aspects. The fossil record of albanerpetontids spans over 160 million years from the Middle Jurassic to the beginning of the Pleistocene, about 2.13–2 million years ago.

Albanerpetontidae Temporal range: Middle Jurassic – Pleistocene Bathonian–Gelasian PreꞒ Ꞓ O S D C P T J K Pg N
Fossil of Celtedens ibericus, showing the remains of scales surrounding the body in grey
Skull of Yaksha peretti
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Amphibia
Order:	†Allocaudata Fox and Naylor, 1982
Family:	†Albanerpetontidae Fox and Naylor, 1982
Genera
†Albanerpeton †Anoualerpeton †Celtedens †Shirerpeton †Wesserpeton †Yaksha
Synonyms
Albanerpetonidae Albanerpetidae

History of research

 

Holotype fossil of Celtedens megacephalus from Italy

The earliest specimen of an albanerpetontid to be discovered was that of Celtedens megacephalus from the Early Cretaceous (Albian) Pietraroja Plattenkalk of Italy, described by Oronzio Gabriele Costa in 1864, and originally placed in the genus Triton, a junior synonym of the salamander genus Triturus.^[1] Jaw elements of albanerpetontids from the Cretaceous of North America were assigned to the salamander genus Prosiren by Richard Estes in 1969, erecting the family Prosirenidae to accommodate the genus.^[2] Prosiren was originally described by Coleman J. Goin and Walter Auffenberg in 1958, based on vertebrae found in Cretaceous aged deposits in Texas.^[3] Albanerpeton, the type genus of the family was first named by Estes and Robert Hoffstetter in 1976 for the species of A. inexpectatum described from a large number of jaws and frontal bones from a Miocene aged fissure fill deposit near Saint-Alban-de-Roche in France, and was initially classified as a salamander, and placed in the family Prosirenidae alongside Prosiren due to the morphological similarity with the jaw fragments attributed to Prosiren by Estes (1969).^[4] Richard Fox and Bruce Naylor in 1982 realised that Albanerpeton was not a salamander, noting that the holotype vertebra of Prosiren was different to those of albanerpetontids, concluding that Albanerpeton was "well isolated from salamanders" and that it "seems no nearer phyletically to any other known amphibians, from Devonian to Recent" erecting the family Albanerpetontidae and the order Allocaudata to accommodate it.^[5]

Description

 

Bones of the only articulated albanerpetontid skull, Yaksha peretti, vomer not shown

Albanerpetontids were small (several cm to several tens of centimetres in length) and superficially lizard-like. The skin of albanerpetontids was embedded with bony, fish like scales. The forelimbs only had 4 digits, while retaining 5 digits on the hindlimbs. The morphology of the complete 3 dimensionally preserved skull of Yaksha peretti suggests that albanerpetontids had ballistic tongues akin to those of chameleons and plethodontid salamanders, as evidenced by the presence of an elongated rod shaped bone in the jaw cavity, dubbed the hyoid entoglossal process, which in life was embedded within the tongue. Analogous bones exists in chameleons and plethodontids, which allow rapid propulsion of the tongue.^[6] A hyoid entoglossal process is also known from Celtedens megacephalus, suggesting that the presence of a ballistic tongue is characteristic for the group.^[7][6] Distinguishing apomorphic traits characteristic of albanerpetontids include a complex mortise and tenon like joint connecting the dentary bones at the front of the jaw, teeth which are non-pedicellate and slightly tricuspid (bearing three cusps), the frontal bones of the skull display raised polygonal sculpturing, and three anterior cervical components form an 'atlas–axis' complex, similar to that of amniotes.^[8]

Paleobiology

 

Life restoration of Albanerpeton inexpectatum

The morphology of albanerpetontids suggests that they were sit-and-wait terrestrial predators and fed on invertebrates, similar to living plethodontids. The fact that the skull of the juvenile paratype of Yaksha was around 1/4 of the size of the adult suggests that albanerpetontids grew by direct development and did not have a metamorphic larval stage.^[6] It has been suggested that albanerpetontids absorbed oxygen entirely through the skin via cutaneous respiration and lacked lungs like plethodontid salamanders, due to the length of the hyoid entoglossal process, which may have made normal breathing difficult.^[6] This proposal is supported by the internal vascularisation and lack of Sharpey's fibres in the frontal bones.^[9] Albanerpetontids are associated with both wet and dry environments, but it is unclear how tolerant they were of dry habitats, and they may have been confined to wet microhabitats in dry areas.^[10] Some authors have suggested that they were likely fossorial, using their heads to burrow, but this has been questioned by other authors.^[11]

Distribution

The distribution of albanerpetontids is largely confined to Eurasia and North America, with remains also known from Morocco in North Africa.^[12][13] The first albanerpetontids are known from the western Palearctic (Europe and North Africa) in the Middle Jurassic (Bathonian ~168–166 million years ago), with the oldest records of the group in North America and Asia dating to the Early Cretaceous. The last known remains of albanerpetontids in North America are from the Paskapoo Formation in Canada, dating to the Paleocene. All other Cenozoic members of the family, belonging to the genus Albanerpeton, are known from Europe and Anatolia, from the Oligocene onwards (there is no fossil record of albanerpetontids during the Eocene) until their final appearance in Northern Italy during the Early Pleistocene, around 2.13-2 million years ago.^{[13][14][15][8]} Another possible late record is known from northern Spain, dating to around 2.2-2.6 million years ago.^[16]

Classification

Albanerpetontids were long thought to be salamanders because of their small size and generalized body plans.^[17] However, these features are now thought to be ancestral for lissamphibians and not indicative of close relationships between the two groups.^[18] Albanerpetontids share with living lissamphibians an atlanto-occipital joint with two cotyles, a four fingered forelimb (manus), ectochordal (spoon shaped with open centra) vertebrae with cylindrical centra, ribs that do not encircle the body, and a salamander-like quadrate–squamosal articulation, but are distinguished from the three living groups of lissamphibians by their possession of keratinized claw sheaths and their retention of skull bones lost in other lissamphibians, including epipterygoids, supraoccipitals and large palatines, as well as the absence of pedicellate teeth or a wide parasphenoid cultriform process.^[6] Albanerpetontids are now recognized as a distinct clade of lissamphibians separate from the three living orders of amphibians – Anura (frogs), Caudata (salamanders), and Gymnophiona (caecilians). Many studies show them as more closely related to frogs and salamanders than to caecilians,^[19] but bootstrap and Bayesian analyses show that this result is not robust and that they could also be sister-group of the Lissamphibia,^[20] or as most closely related to caecillians.^[21] The presence of epipterygoids and a separate supraoccipital at least argues against a position within Batrachia.^[8] A phylogenetic analysis in 2020 among lissamphibian relationships using multiple methods found no consensus for the position of Albanerpetontidae in relation to other lissamphibians, but they were always placed closer to lissamphibians than to other extinct groups of amphibians, such as lepospondyls and temnospondyls.^[6]

Taxonomy

• Genus Shirerpeton Matsumoto & Evans, 2018^[8]
  • Shirerpeton isajii Matsumoto & Evans, 2018 Early Cretaceous, Japan
• Genus Wesserpeton Sweetman & Gardner 2013
  • Wesserpeton evansae Sweetman & Gardner 2013 Early Cretaceous, United Kingdom
• Genus Anoualerpeton Gardner, Evans & Sigogneau-Russell 2003
  • Anoualerpeton priscus Gardner, Evans & Sigogneau-Russell 2003 Middle Jurassic, United Kingdom
  • Anoualerpeton unicus Gardner, Evans & Sigogneau-Russell 2003 Late Jurassic, Morocco
• Genus Celtedens McGowan & Evans 1995 Late Jurassic-Early Cretaceous, Europe
  • Celtedens megacephalus (Costa 1864) Early Cretaceous, Italy, United Kingdom
  • Celtedens ibericus McGowan & Evans 1995 Early Cretaceous, Spain
• Genus Albanerpeton Estes & Hoffstetter 1976
  • Albanerpeton arthridion Fox & Naylor 1982 Early Cretaceous, United States
  • Albanerpeton ektopistikon Carrano et al. 2022 Early Cretaceous, United States
  • Clade "Gracile-snouted"
    • Albanerpeton gracilis Gardner 2000 Late Cretaceous, North America
    • Albanerpeton cifellii Gardner 1999 Late Cretaceous, United States
    • Albanerpeton galaktion Fox & Naylor 1982 Late Cretaceous, North America
  • Clade "Robust-snouted"
    • Albanerpeton nexuosus Estes 1981 Late Cretaceous, North America
    • Albanerpeton pannonicus Venczel & Gardner 2005 latest Miocene-Early Pleistocene Hungary, Italy
    • Albanerpeton inexpectatum Estes & Hoffstetter 1976 Early Oligocene- Late Miocene, Europe
• Genus Yaksha Daza et al, 2020
  • Yaksha perettii Daza et al, 2020 Late Cretaceous, Myanmar
• Fragmentary remains of albanerpetontids are also known from the Bathonian aged Anoual Formation of Morocco,^[22] the Bathonian aged Aveyron locality of France,^[8][23] the Tithonian aged Chassiron locality of France,^[24] the Berriasian aged Cherves-de-Cognac locality and Angeac-Charente bonebed of France,^[25] the Cenomanian-Turonian Khodzhakul and Bissekty Formations of Uzbekistan, originally assigned to the dubious genus Nukusurus^[26] and a variety of localities in Europe dating to the Late Cretaceous, including Hungary (Csehbánya Formation), France, Spain and Romania (Hațeg Island), which may be referrable to Albanerpeton.^[27][10]

Phylogeny

From Daza et al 2020.^[6]

	Anoualerpeton   Celtedens Uña taxon      Wesserpeton      Albanerpeton arthridion      Albanerpeton gracilis + Albanerpeton galaktion      Albanerpeton cifellii      Yaksha      Shirerpeton      Albanerpeton nexuosum      Albanerpeton pannonicum Paskapoo sp Albanerpeton inexpectatum

References

1. O. G. Costa. 1864. Paleontologia del Regno di Napoli. Parte III [Paleontology of the Kingdom of Naples. Part III]. Atti dell'Accademia Pontaniana 8:1–192
2. Estes, R. (October 1969). "Prosirenidae, a New Family of Fossil Salamanders". Nature. 224 (5214): 87–88. Bibcode:1969Natur.224...87E. doi:10.1038/224087a0. ISSN 0028-0836. S2CID 4165755.
3. Goin, Coleman J. (1958). New salamanders of the family Sirenidae from the Cretaceous of North America. Chicago Natural History Museum. OCLC 670082421.
4. R. Estes and R. Hoffstetter. 1976. Les urodèles du Miocène de La Grive-Saint-Alban (Isère, France) [The urodeles from the Miocene of La Grive-Saint-Alban (Isère, France)]. Bulletin du Muséum National d'Histoire Naturelle, Sciences de la Terre 57:297–343
5. Fox, Richard C.; Naylor, Bruce G. (1982-01-01). "A reconsideration of the relationships of the fossil amphibian Albanerpeton". Canadian Journal of Earth Sciences. 19 (1): 118–128. Bibcode:1982CaJES..19..118F. doi:10.1139/e82-009. ISSN 0008-4077.
6. Daza, Juan D.; Stanley, Edward L.; Bolet, Arnau; Bauer, Aaron M.; Arias, J. Salvador; Čerňanský, Andrej; Bevitt, Joseph J.; Wagner, Philipp; Evans, Susan E. (2020-11-06). "Enigmatic amphibians in mid-Cretaceous amber were chameleon-like ballistic feeders". Science. 370 (6517): 687–691. Bibcode:2020Sci...370..687D. doi:10.1126/science.abb6005. ISSN 0036-8075. PMID 33154135. S2CID 226254862.
7. McGowan, Gerard J. (May 2002). "Albanerpetontid amphibians from the Lower Cretaceous of Spain and Italy: a description and reconsideration of their systematics". Zoological Journal of the Linnean Society. 135 (1): 1–32. doi:10.1046/j.1096-3642.2002.00013.x. ISSN 1096-3642.
8. Matsumoto, Ryoko; Evans, Susan E. (2018). "The first record of albanerpetontid amphibians (Amphibia: Albanerpetontidae) from East Asia". PLOS ONE. 13 (1): e0189767. Bibcode:2018PLoSO..1389767M. doi:10.1371/journal.pone.0189767. PMC 5752013. PMID 29298317.
9. Skutschas, Pavel P.; Kolchanov, Veniamin V.; Gardner, James D. (2021-02-02). "Microanatomy and histology of frontal bones in two species of Albanerpeton sensu lato (Lissamphibia: Albanerpetontidae) from the Upper Cretaceous Oldman Formation in southeastern Alberta, Canada". Historical Biology. 33 (12): 3604–3616. doi:10.1080/08912963.2021.1881084. ISSN 0891-2963. S2CID 234075025.
10. Carrano, Matthew T.; Oreska, Matthew P. J.; Murch, Abree; Trujillo, Kelli C.; Chamberlain, Kevin R. (2021-08-27). "Vertebrate paleontology of the Cloverly Formation (Lower Cretaceous), III: a new species of Albanerpeton , with biogeographic and paleoecological implications". Journal of Vertebrate Paleontology. 41 (5). doi:10.1080/02724634.2021.2003372. ISSN 0272-4634.
11. Skutschas, Pavel P.; Kolchanov, Veniamin V.; Gardner, James D. (2021-12-02). "Microanatomy and histology of frontal bones in two species of Albanerpeton sensu lato (Lissamphibia: Albanerpetontidae) from the Upper Cretaceous Oldman Formation in southeastern Alberta, Canada". Historical Biology. 33 (12): 3604–3616. doi:10.1080/08912963.2021.1881084. ISSN 0891-2963.
12. Gardner, J.D.; Böhme, M. (2008). Sankey, J.T.; Baszio, S. (eds.). Vertebrate Microfossil Assemblages: Their Role in Paleoecology and Paleobiogeography (PDF). Indianapolis: Indiana University Press. pp. 178–218. Retrieved 9 January 2012.
13. Villa, Andrea; Blain, Hugues-Alexandre; Delfino, Massimo (2018). "The Early Pleistocene herpetofauna of Rivoli Veronese (Northern Italy) as evidence for humid and forested glacial phases in the Gelasian of Southern Alps". Palaeogeography, Palaeoclimatology, Palaeoecology. 490: 393–403. Bibcode:2018PPP...490..393V. doi:10.1016/j.palaeo.2017.11.016. hdl:2318/1652046. ISSN 0031-0182.
14. Macaluso, Loredana; Bertini, Adele; Carnevale, Giorgio; Eronen, Jussi T.; Martinetto, Edoardo; Saarinen, Juha; Villa, Andrea; Capasso, Flavia; Delfino, Massimo (September 2023). "A combined palaeomodelling approach reveals the role as selective refugia of the Mediterranean peninsulas". Palaeogeography, Palaeoclimatology, Palaeoecology. 625: 111699. doi:10.1016/j.palaeo.2023.111699. S2CID 259661844.
15. Georgalis, Georgios L.; Čerňanský, Andrej; Mayda, Serdar (2021-04-13). "Late Paleogene herpetofaunas from the crossroads between two continents – new amphibian and reptile remains from the Oligocene of southern Balkans and Anatolia". Comptes Rendus Palevol (15): 253–257. doi:10.5167/UZH-202599.
16. López-García, Juan Manuel; Piñero, Pedro; Agustí, Jordi; Furió, Marc; Galán, Julia; Moncunill-Solé, Blanca; Ruiz-Sánchez, Francisco Javier; Blain, Hugues-Alexandre; Sanz, Montserrat; Daura, Joan (2023-03-02). "Chronological context, species occurrence, and environmental remarks on the Gelasian site Pedrera del Corral d'en Bruach (Barcelona, Spain) based on the small-mammal associations". Historical Biology: 1–20. doi:10.1080/08912963.2023.2180740. ISSN 0891-2963. S2CID 257316502.
17. Duellman, W.E. & Trueb, L. (1994): Biology of amphibians. The Johns Hopkins University Press
18. Wesserpeton evansae: making 'albanerpetontid' a household name
19. Gardner, J. D. (2001). "Monophyly and affinities of albanerpetontid amphibians (Temnospondyli; Lissamphibia)". Zoological Journal of the Linnean Society. 131 (3): 309–352. doi:10.1111/j.1096-3642.2001.tb02240.x.
20. Marjanović, David; Laurin, Michel (2019). "Phylogeny of Paleozoic limbed vertebrates reassessed through revision and expansion of the largest published relevant data matrix". PeerJ. 6 (e5565): e5565. doi:10.7717/peerj.5565. PMC 6322490. PMID 30631641.
21. Kligman, Ben T.; Gee, Bryan M.; Marsh, Adam D.; et al. (25 January 2023). "Triassic stem caecilian supports dissorophoid origin of living amphibians". Nature. 614 (7946): 102–107. doi:10.1038/s41586-022-05646-5. hdl:10919/113568. ISSN 1476-4687. PMC 9892002. PMID 36697827. S2CID 256272986.
22. Haddoumi, Hamid; Allain, Ronan; Meslouh, Said; Metais, Grégoire; Monbaron, Michel; Pons, Denise; Rage, Jean-Claude; Vullo, Romain; Zouhri, Samir (January 2016). "Guelb el Ahmar (Bathonian, Anoual Syncline, eastern Morocco): First continental flora and fauna including mammals from the Middle Jurassic of Africa" (PDF). Gondwana Research. 29 (1): 290–319. Bibcode:2016GondR..29..290H. doi:10.1016/j.gr.2014.12.004. ISSN 1342-937X.
23. Seiffert J. Urodelan atlas aus dem obersten Bajocien von S.E. Aveyron (Südfrankreich). Palaontol Z. 1969;43:32–6.
24. Vullo, Romain; Abit, Dominique; Ballèvre, Michel; Billon-Bruyat, Jean-Paul; Bourgeais, Renaud; Buffetaut, Éric; Daviero-Gomez, Véronique; Garcia, Géraldine; Gomez, Bernard; Mazin, Jean-Michel; Morel, Séverin (July 2014). "Palaeontology of the Purbeck-type (Tithonian, Late Jurassic) bonebeds of Chassiron (Oléron Island, western France)". Comptes Rendus Palevol. 13 (5): 421–441. doi:10.1016/j.crpv.2014.03.003.
25. Ronan Allain, Romain Vullo, Lee Rozada, Jérémy Anquetin, Renaud Bourgeais, et al.. Vertebrate paleobiodiversity of the Early Cretaceous (Berriasian) Angeac-Charente Lagerstätte (southwestern France): implications for continental faunal turnover at the J/K boundary. Geodiversitas, Museum National d'Histoire Naturelle Paris, In press. ffhal-03264773f
26. Skutschas, Pavel P. (2013). "Mesozoic salamanders and albanerpetontids of Middle Asia, Kazakhstan, and Siberia". Palaeobiodiversity and Palaeoenvironments. 93 (4): 441–457. doi:10.1007/s12549-013-0126-8. S2CID 140159226.
27. Csiki-Sava, Zoltan; Buffetaut, Eric; Ősi, Attila; Pereda-Suberbiola, Xabier; Brusatte, Stephen L. (2015-01-08). "Island life in the Cretaceous - faunal composition, biogeography, evolution, and extinction of land-living vertebrates on the Late Cretaceous European archipelago". ZooKeys (469): 1–161. doi:10.3897/zookeys.469.8439. ISSN 1313-2970. PMC 4296572. PMID 25610343.

External links

• Albanerpetontidae phylogeny.