# Eolydekkerina > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Eolydekkerina > Markdown URL: https://mediated.wiki/source/Eolydekkerina.md > Source: https://en.wikipedia.org/wiki/Eolydekkerina > Source revision: 1212631454 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) Extinct genus of temnospondyls Eolydekkerina Temporal range: Early Triassic Restoration of Eolydekkerina magna Scientific classification Kingdom: Animalia Phylum: Chordata Clade: Tetrapoda Order: †Temnospondyli Suborder: †Stereospondyli Family: †Lydekkerinidae Genus: †Eolydekkerina Shishkin et al., 1996 Type species †Eolydekkerina magna Shishkin et al., 1996 ***Eolydekkerina*** is an extinct [genus](/source/Genus) of [temnospondyl](/source/Temnospondyl) from the [Early Triassic](/source/Early_Triassic) of South Africa. It belongs to the family [Lydekkerinidae](/source/Lydekkerinidae), along with the closely related genus *[Lydekkerina](/source/Lydekkerina)*. It is known from a single [type species](/source/Type_species), *Eolydekkerina magna*, which was named in 1996 from a part of the [Beaufort Group](/source/Beaufort_Group) called the [*Lystrosaurus* Assemblage Zone](/source/Lystrosaurus_Assemblage_Zone).[1] ## Description *Eolydekkerina* is known from two specimens: a skull lacking the lower jaws and a poorly lower jaw, not associated with the skull. At 13 centimetres (5.1 in) in length, the skull of *Eolydekkerina* is larger than that of any *Lydekkerina* specimen. The snout is proportionally much longer, and the eye sockets are placed farther apart than they are in *Lydekkerina*. The proportions of the skull in *Eolydekkerina* are similar to those of the Australian lydekkerinid genus *[Chomatobatrachus](/source/Chomatobatrachus)*. However, *Eolydekkerina* shares more features in common with *Lydekkerina*, including the nearly identical shape of bones at the back of the skull. The skull is roughly triangular in shape when viewed from above, with straight side margins. The margins of the eye socket are raised and the middle of the snout is slightly indented. Shallow grooves run along the surface of the skull behind the eye sockets and below the nostril openings.[1] The lengthened skull of *Eolydekkerina*, while different from that of *Lydekkerina*, is similar to those of the related rhinesuchids and [capitosaurians](/source/Capitosauria). The short skull of *Lydekkerina* is thought to be a [derived](/source/Synapomorphy) or advanced characteristic, suggesting that *Lydekkerina* evolved from a more typical longer-skulled temnospondyl. Since temnospondyl skulls tend to lengthen as individuals of a species age, the skull of *Lydekkerina* may represent a juvenile form, while the skull of *Eolydekkerina* represents a fully-grown adult form. If *Lydekkerina* is the descendant of *Eolydekkerina*, it likely evolved by retaining juvenile characteristics into adulthood in a condition known as [paedomorphosis](/source/Paedomorphosis).[1] ## Paleoenvironment Remains of *Eolydekkerina* were found in the lower part of the *Lystrosaurus* Assemblage Zone, a deposit that preserves very few amphibians. Amphibians become more numerous in younger parts of the *Lystrosaurus* Assemblage Zone with most specimens attributable to either *Lydekkerina* or to the [dissorophoid](/source/Dissorophoid) *[Micropholis](/source/Micropholis_(amphibian))*. Several species of the family [Rhytidosteidae](/source/Rhytidosteidae) have also been identified from the upper part of the *Lystrosaurus* Assemblage Zone. When fossils of *Eolydekkerina* were first found, they were thought to belong to a rhytidosteid, as a rhytidosteid called *[Pneumatostega](/source/Pneumatostega)* had already been found in this part of the assemblage zone. The lower *Lystrosaurus* Assemblage Zone is dominated by the [synapsid](/source/Synapsid) *[Lystrosaurus](/source/Lystrosaurus)*, as well as reptiles such as *[Owenetta](/source/Owenetta)* and *[Proterosuchus](/source/Proterosuchus)*. Most small-bodied lydekkerinids such as *Lydekkerina* are found in this type of assemblage. Lydekkerinids of similar size to *Eolydekkerina* (such as *Chomatobatrachus*) are usually found in amphibian-dominated assemblages where *Lystrosaurus* is not present. Therefore, the presence of *Eolydekkerina* in a reptile-dominated environment is unusual.[1] ## References 1. ^ [***a***](#cite_ref-SRK96_1-0) [***b***](#cite_ref-SRK96_1-1) [***c***](#cite_ref-SRK96_1-2) [***d***](#cite_ref-SRK96_1-3) Shishkin, M. A.; Rubidge, B. S.; Kitching, J. W. (1996). "A New Lydekkerinid (Amphibia, Temnospondyli) from the Lower Triassic of South Africa: Implications for Evolution of the Early Capitosauroid Cranial Pattern". *Philosophical Transactions of the Royal Society B: Biological Sciences*. **351** (1347): 1635. [doi](/source/Doi_(identifier)):[10.1098/rstb.1996.0147](https://doi.org/10.1098%2Frstb.1996.0147). v t e Stereospondyli Kingdom: Animalia Phylum: Chordata Clade: Tetrapodomorpha Order: Temnospondyli Tetrapodomorpha see Tetrapodomorpha Temnospondyli see Temnospondyli Stereospondyli see below↓ Stereospondyli Stereospondyli Arachana Capulomala Peltobatrachus Lapillopsidae Lapillopsis Manubrantlia Rhigerpeton Rotaurisaurus Rhinesuchidae Australerpeton? Broomistega Laccosaurus Parapytanga? Rastosuchus Rhineceps Rhinesuchoides Rhinesuchus Uranocentrodon Lydekkerinidae Chomatobatrachus Cryobatrachus Deltacephalus Eolydekkerina Indobenthosuchus Luzocephalus? Lydekkerina Capitosauria Antarctosuchus Bukobaja Calmasuchus Capitosaurus Cherninia Cyclotosaurus Edingerella Eocyclotosaurus Eryosuchus Heptasaurus Huangfuchuansuchus Jammerbergia Kestrosaurus Kupferzellia Mastodonsaurus Meyerosuchus Odenwaldia Paracyclotosaurus Parotosuchus Quasicyclotosaurus Procyclotosaurus Promastodonsaurus Rhadalognathus Samarabatrachus Sassenisaurus Sclerothorax Selenocara Stanocephalosaurus Stenotosaurus Subcyclotosaurus Tatrasuchus Vladlenosaurus Volgasaurus Volgasuchus Warrenisuchus Watsonisuchus Wellesaurus Wetlugasaurus Xenotosuchus Yuanansuchus Trematosauria see below↓ Trematosauria Trematosauria Almasaurus Bothriceps Callistomordax Chinlestegophis Keratobrachyops Laidleria Latiscopus Qantas Rileymillerus Syrtosuchus Uruyiella Benthosuchidae Benthosuchus Kwatisuchus Trematosauridae Angusaurus Aphaneramma Cosgriffius Erythrobatrachus Gonioglyptus Hyperokynodon Icanosaurus Indolyrocephalus Inflectosaurus Lyrocephaliscus Microposaurus Panchetosaurus Platystega Prothoosuchus Stoschiosaurus Tertrema Tertremoides Thoosuchus Tirraturhinus Trematolestes Trematosuchoides Trematosaurus Trematosuchus Trematotegmen Wantzosaurus Metoposauridae Anaschisma Apachesaurus Arganasaurus Buettnererpeton Dutuitosaurus Metoposaurus Panthasaurus Rhytidosteidae Boreopelta Mahavisaurus Nanolania Peltostega Pneumatostega Rhytidosteus Sangaia Trucheosaurus Derwentiinae Arcadia Acerastia Deltasaurus Derwentia Indobrachyops Rewana Chigutisauridae Arenaerpeton Chigutisaurus Compsocerops Koolasuchus Pelorocephalus Siderops Brachyopidae Banksiops Bathignathus Batrachosaurus Batrachosuchoides Batrachosuchus Blinasaurus Brachyops Gobiops Hadrokkosaurus Notobrachyops Platycepsion Sinobrachyops Vanastega Vigilius Xenobrachyops Plagiosauridae Gerrothorax Megalophthalma Plagiobatrachus Plagiorophus Plagiosaurus Plagioscutum Plagiosternum Plagiosuchus See also: Trematosauroidea Metoposauroidea Rhytidosteoidea Brachyopomorpha Brachyopoidea Plagiosauroidea Category Taxon identifiers Eolydekkerina Wikidata: Q5381791 GBIF: 4815755 IRMNG: 1156508 Paleobiology Database: 266405 --- Adapted from the Wikipedia article [Eolydekkerina](https://en.wikipedia.org/wiki/Eolydekkerina) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Eolydekkerina?action=history)). 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