''Wannia'' is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of basal

phytosaur Phytosaurs (Φυτόσαυροι in Greek, meaning 'plant lizard') are an extinct group of large, mostly semiaquatic Late Triassic archosauriform or basal archosaurian reptiles. Phytosaurs belong to the order Phytosauria and are sometimes ref ...

reptile Reptiles, as commonly defined, are a group of tetrapods with an ectothermic metabolism and Amniotic egg, amniotic development. Living traditional reptiles comprise four Order (biology), orders: Testudines, Crocodilia, Squamata, and Rhynchocepha ...

known from the

Late Triassic The Late Triassic is the third and final epoch (geology), epoch of the Triassic geologic time scale, Period in the geologic time scale, spanning the time between annum, Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch a ...

(late

Carnian The Carnian (less commonly, Karnian) is the lowermost stage (stratigraphy), stage of the Upper Triassic series (stratigraphy), Series (or earliest age (geology), age of the Late Triassic Epoch (reference date), Epoch). It lasted from 237 to 227.3 ...

or early

Norian The Norian is a division of the Triassic geological period, Period. It has the rank of an age (geology), age (geochronology) or stage (stratigraphy), stage (chronostratigraphy). It lasted from ~227.3 to Mya (unit), million years ago. It was prec ...

stage) of

Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...

, southern United States. It contains a single species, ''Wannia scurriensis'', which is known from a single specimen. This species was originally named as a species referred to ''

Paleorhinus ''Paleorhinus'' (Greek: ''"Old Nose"'') is an extinct genus of widespread basal phytosaur known from the Late Triassic (late Carnian stage). The genus was named in 1904 based on the type species ''Paleorhinus bransoni'', which is known from Wyo ...

'' and later was considered as a possible

junior synonym In taxonomy, the scientific classification of living organisms, a synonym is an alternative scientific name for the accepted scientific name of a taxon. The botanical and zoological codes of nomenclature treat the concept of synonymy differently. ...

of ''

Paleorhinus bransoni ''Paleorhinus'' (Greek: ''"Old Nose"'') is an extinct genus of widespread basal phytosaur known from the Late Triassic (late Carnian stage). The genus was named in 1904 based on the type species ''Paleorhinus bransoni'', which is known from Wyom ...

''. However its re-description revealed five

autapomorphies In phylogenetics, an autapomorphy is a distinctive feature, known as a derived trait, that is unique to a given taxon. That is, it is found only in one taxon, but not found in any others or outgroup taxa, not even those most closely related to ...

, and a phylogenetic position as the most basal known phytosaur, justifying the erection of a new generic name for the species.

Discovery and naming

''Wannia'' was first described and named by the late Dr. Wann Langston Jr. in

1949 Events January * January 1 – A United Nations-sponsored ceasefire brings an end to the Indo-Pakistani War of 1947. The war results in a stalemate and the division of Kashmir, which still continues as of 2025 * January 2 – Luis ...

as a species referable to ''

'', ''P. scurriensis''. An alternative generic name, ''Wannia'', was proposed by Michelle R. Stocker in

2013 2013 was the first year since 1987 to contain four unique digits (a span of 26 years). 2013 was designated as: *International Year of Water Cooperation *International Year of Quinoa Events January * January 5 – 2013 Craig, Alask ...

creating the

new combination In Taxonomy (biology), biological taxonomy, a combinatio nova (abbreviated comb. nov. or n. comb.) refers to the formal renaming of an organism's scientific name when it is transferred to a different genus, reclassified within a different specie ...

''Wannia scurriensis''. The generic name honors Langston for his extensive work on

archosaur Archosauria () or archosaurs () is a clade of diapsid sauropsid tetrapods, with birds and crocodilians being the only extant taxon, extant representatives. Although broadly classified as reptiles, which traditionally exclude birds, the cladistics ...

palaeontology, and the

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

refers to the

Scurry County Scurry County is a county located in the U.S. state of Texas. As of the 2020 census, its population was 16,932. Its county seat is Snyder, which is the home for Western Texas College. Scurry County is named for Confederate General William S ...

where the holotype was found. ''Wannia'' is known solely from the

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

TTU P-00539, a partial

skull The skull, or cranium, is typically a bony enclosure around the brain of a vertebrate. In some fish, and amphibians, the skull is of cartilage. The skull is at the head end of the vertebrate. In the human, the skull comprises two prominent ...

preserved in two parts housed at

Texas Tech University Texas Tech University (Texas Tech, Tech, or TTU) is a public university, public research university in Lubbock, Texas, United States. Established on February 10, 1923, and called Texas Technological College until 1969, it is the flagship instit ...

. TTU P-11422, a partial juvenile skull, had also been referred to ''"P." scurriensis'', however Stocker (2013) found no basis for this referral as the specimens do not share any

synapomorphies In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to ...

. The holotype was collected near

Lake Alan Henry Lake Alan Henry is a reservoir situated in the upper Brazos River Basin in the United States. Created by the construction of the John T. Montford Dam in 1993, it is operated and used as a future tertiary water supply by the city of Lubbock, Texa ...

, 4 km northeast of the town of Camp Springs, from the Camp Springs Formation of the

Dockum Group The Dockum is a Late Triassic (approximately late Carnian through Rhaetian, or 223–200 Ma) geologic group found primarily on the Llano Estacado of western Texas and eastern New Mexico with minor exposures in southwestern Kansas, eastern Color ...

. Previously known as the Camp Springs Conglomerate, this unit probably correlates with the lower member of the Santa Rosa Sandstone in Texas and the Tecololito Member of the Santa Rosa Formation in New Mexico. The age of this unit is not precisely known, it was originally considered to be late

based on correlations with the Opponitzer Limestone of Austria, using the presence of '' Dolerosaurus'', which was previously considered to be a member of ''Paleorhinus''. However, recent

zircon Zircon () is a mineral belonging to the group of nesosilicates and is a source of the metal zirconium. Its chemical name is zirconium(IV) silicate, and its corresponding chemical formula is Zr SiO4. An empirical formula showing some of th ...

radiometric dating Radiometric dating, radioactive dating or radioisotope dating is a technique which is used to Chronological dating, date materials such as Rock (geology), rocks or carbon, in which trace radioactive impurity, impurities were selectively incorporat ...

suggests that the Santa Rosa Sandstone is equivalent to the

-aged Shinarump Member. Furthermore, the Post Quarry which is within the stratigraphically higher

Cooper Canyon Formation The Cooper Canyon Formation is a geological formation of Norian age in Texas. It is one of several formations encompassed by the Dockum Group.Weishampel, David B; et al. (2004).Dinosaur distribution (Late Triassic, North America)" In: Weishampel, ...

of the Dockum Group was recently demonstrated to be mid Norian (220–215 Ma). Thus the most probable age for the Camp Springs Formation and the lower member of the Santa Rosa Sandstone is latest Carnian or early Norian.

Description

Stocker (2013) diagnosed ''Wannia scurriensis'' using five unambiguous

(unique traits) and additionally by a unique combination of characters. Unlike all other phytosaurs, the basitubera, areas at the base of the skull in front of its attachment point with the neck, are widely separated mediolaterally. A distinctive ridge is present on the lateral surface of the

jugal bone The jugal is a skull bone found in most reptiles, amphibians and birds. In mammals, the jugal is often called the malar or zygomatic bone, zygomatic. It is connected to the quadratojugal and maxilla, as well as other bones, which may vary by spe ...

. A thickened shelf is present along the posteroventral edge of an expanded "wing" formed by the

pterygoid bone The pterygoid is a paired bone forming part of the palate of many vertebrates, behind the palatine bone In anatomy, the palatine bones (; derived from the Latin ''palatum'') are two irregular bones of the facial skeleton in many animal specie ...

and the

quadrate bone The quadrate bone is a skull bone in most tetrapods, including amphibians, sauropsids ( reptiles, birds), and early synapsids. In most tetrapods, the quadrate bone connects to the quadratojugal and squamosal bones in the skull, and forms up ...

. A swelling on the

nasal bone The nasal bones are two small oblong bones, varying in size and form in different individuals; they are placed side by side at the middle and upper part of the face and by their junction, form the bridge of the upper one third of the nose. Eac ...

is present behind the posterior borders of the nares. Finally, the "septomaxillae", probably not homologous to the septomaxillae of

squamate Squamata (, Latin ''squamatus'', 'scaly, having scales') is the largest Order (biology), order of reptiles; most members of which are commonly known as Lizard, lizards, with the group also including Snake, snakes. With over 11,991 species, it i ...

s and

synapsid Synapsida is a diverse group of tetrapod vertebrates that includes all mammals and their extinct relatives. It is one of the two major clades of the group Amniota, the other being the more diverse group Sauropsida (which includes all extant rept ...

s, do not contact one another and do not form part of the internarial septum. Eight characters are shared by ''Wannia'' and all other phytosaurs (

), including nares that are directed dorsally and the presence of separate ossification, the septomaxilla, anterior to the nasals and surrounded by the

premaxilla The premaxilla (or praemaxilla) is one of a pair of small cranial bones at the very tip of the upper jaw of many animals, usually, but not always, bearing teeth. In humans, they are fused with the maxilla. The "premaxilla" of therian mammals h ...

. Although a

synonymy A synonym is a word, morpheme, or phrase that means precisely or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are a ...

between ''Wannia scurriensis'' and ''

'' was previously suggested, ''Wannia scurriensis'' differs from ''Paleorhinus bransoni'' in lacking a contact between the premaxilla and

palatine bone In anatomy, the palatine bones (; derived from the Latin ''palatum'') are two irregular bones of the facial skeleton in many animal species, located above the uvula in the throat. Together with the maxilla, they comprise the hard palate. Stru ...

, as seen in '' Paleorhinus angustifrons'' and '' Ebrachosuchus neukami''. Additionally, ''W. scurriensis'' differs from both species of ''Paleorhinus'' in the presence of a ridge, rather than a row of nodes, on the lateral surface of the jugal. The small partial skull previously catalogued as referable to this species, TTU P-11422, does not share any diagnostic characters with the holotype. The specimens can be compared only in the area surrounding the right antorbital fenestra. Although TTU P-11422 does have a large antorbital fossa with a slightly posterodorsally inclined antorbital fenestra as in ''W. scurriensis'', the nasals just posterior to the nares are not swollen in contrast to the autapomorphic condition seen in the latter. However, a further preparation of TTU P-11422 may reveal additional morphological traits.

References

{{Taxonbar, from=Q16760255 Phytosauria Prehistoric reptile genera Late Triassic reptiles of North America Paleontology in Texas Fossil taxa described in 2013 Taxa named by Michelle R. Stocker