Ianthasaurus

Last updated

Ianthasaurus
Temporal range: Late Carboniferous,
~304  Ma
O
S
D
C
P
T
J
K
Pg
N
Ianthasaurus223DB.jpg
Life restoration
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Clade: Synapsida
Family: Edaphosauridae
Genus: Ianthasaurus
Reisz and Berman, 1986
Type species
Ianthasaurus hardestii
Reisz & Berman, 1986

Ianthasaurus is an extinct genus of small edaphosaurids from the Late Carboniferous.

Contents

Description

Size comparison Ianthasaurus Scale.svg
Size comparison

It is one of the smallest pelycosaurs known, with an 8 cm skull and a total body length of 75 cm. [1] Ianthasaurus lacks many of the spectacular specializations seen in Edaphosaurus . For example, the marginal dentition of Ianthasaurus is similar to that of insectivorous reptiles, with slender conical teeth which are slightly recurved at the tips, and there is a slight development of a caniniform region. The palatal and mandibular dentition is unspecialized, and there are no batteries of teeth for crushing of plant materials. Also unlike Edaphosaurus , Ianthasaurus was lightly built and was probably quite agile. The skull was similar to that of Haptodus , a sphenacodontid, though they were distantly related.

Discovery

It was named by Robert R. Reisz and David Berman in 1986. [2] [3] It was discovered by them in the Upper Pennsylvanian Rock Lake Shale near Garnett, Kansas. [2]

See also

Related Research Articles

<i>Edaphosaurus</i> Extinct genus of synapsids

Edaphosaurus is a genus of extinct edaphosaurid synapsids that lived in what is now North America and Europe around 303.4 to 272.5 million years ago, during the late Carboniferous to early Permian periods. American paleontologist Edward Drinker Cope first described Edaphosaurus in 1882, naming it for the "dental pavement" on both the upper and lower jaws, from the Greek edaphos έδαφος and σαῦρος ("lizard").

Sphenacodontidae Extinct family of synapsids

Sphenacodontidae is an extinct family of small to large, advanced, carnivorous, Late Pennsylvanian to middle Permian pelycosaurs. The most recent one, Dimetrodon angelensis, is from the late Kungurian or early Roadian San Angelo Formation. However, given the notorious incompleteness of the fossil record, a recent study concluded that the Sphenacodontidae may have become extinct as recently as the early Capitanian. Primitive forms were generally small, but during the later part of the early Permian these animals grew progressively larger, to become the top predators of their environments. Sphenacodontid fossils are so far known only from North America and Europe.

Sphenacodontia Clade of synapsids

Sphenacodontia is a stem-based clade of derived synapsids. It was defined by Amson and Laurin (2011) as "the largest clade that includes Haptodus baylei, Haptodus garnettensis and Sphenacodon ferox, but not Edaphosaurus pogonias". They first appear during the Late Pennsylvanian epoch. From the end of the Carboniferous to the end of the Permian, most of them remained large, with only some secondarily becoming small in size.

Eupelycosauria Clade of synapsids

Eupelycosauria is a large clade of animals characterized by the unique shape of their skull, encompassing all mammals and their closest extinct relatives. They first appeared 308 million years ago during the Early Pennsylvanian epoch, with the fossils Archaeothyris and perhaps an even earlier genus, Protoclepsydrops, representing just one of the many stages in the evolution of mammals, in contrast to their earlier amniote ancestors.

<i>Petrolacosaurus</i> Genus of tetrapods

Petrolacosaurus is an extinct genus of diapsid reptile from the late Carboniferous period. It was a small, 40-centimetre (16 in) long reptile, and the earliest known reptile with two temporal fenestrae. This means that it was at the base of Diapsida, the largest and most successful radiation of reptiles that would eventually include all modern reptile groups, as well as dinosaurs and other famous extinct reptiles such as plesiosaurs, ichthyosaurs, and pterosaurs. However, Petrolacosaurus itself was part of Araeoscelida, a short-lived early branch of the diapsid family tree which went extinct in the mid-Permian.

Caseidae Extinct family of synapsids

Caseidae is an extinct family of synapsids from the Carboniferous and Permian period. It was a widespread group of very primitive herbivorous, possibly aquatic synapsids, which appeared during the late Carboniferous and persisted over 30 million years until the late middle Permian. Estemmenosuchids replaced the caseids as the dominant megaherbivores of the Wordian age.

<i>Sphenacodon</i> Extinct genus of synapsids

Sphenacodon is an extinct genus of synapsid that lived from about 300 to about 280 million years ago (Ma) during the Late Carboniferous and Early Permian periods. Like the closely related Dimetrodon, Sphenacodon was a carnivorous member of the Eupelycosauria family Sphenacodontidae. However, Sphenacodon had a low crest along its back, formed from blade-like bones on its vertebrae instead of the tall dorsal sail found in Dimetrodon. Fossils of Sphenacodon are known from New Mexico and the Utah–Arizona border region in North America.

<i>Secodontosaurus</i> Extinct genus of synapsids

Secodontosaurus is an extinct genus of "pelycosaur" synapsids that lived from between about 285 to 272 million years ago during the Early Permian. Like the well known Dimetrodon, Secodontosaurus is a carnivorous member of the Eupelycosauria family Sphenacodontidae and has a similar tall dorsal sail. However, its skull is long, low, and narrow, with slender jaws that have teeth that are very similar in size and shape—unlike the shorter, deep skull of Dimetrodon, which has large, prominent canine-like teeth in front and smaller slicing teeth further back in its jaws. Its unusual long, narrow jaws suggest that Secodontosaurus may have been specialized for catching fish or for hunting prey that lived or hid in burrows or crevices. Although no complete skeletons are currently known, Secodontosaurus likely ranged from about 2 to 2.7 metres (7–9 ft) in length, weighing up to 110 kilograms (250 lb).

<i>Mycterosaurus</i> Extinct genus of tetrapods

Mycterosaurus is an extinct genus of synapsids belonging to the family Varanopidae. It is classified in the varanopid subfamily Mycterosaurinae. Mycterosaurus is the most primitive member of its family, existing from 290.1 to 272.5 MYA, known to Texas and Oklahoma. It lacks some features that its advanced relatives have.

<i>Eothyris</i> Extinct genus of synapsids

Eothyris is a genus of extinct synapsid in the family Eothyrididae from the early Permian. It was a carnivorous insectivorous animal, closely related to Oedaleops. Only the skull of Eothyris, first described in 1937, is known. It had a 6-centimetre-long (2.4-inch) skull, and its total estimated length is 30 centimetres. Eothyris is one of the most primitive synapsids known and is probably very similar to the common ancestor of all synapsids in many respects. The only known specimen of Eothyris was collected from the Artinskian-lower.

<i>Limnoscelis</i> Genus of diadectomorphs

Limnoscelis was a genus of large diadectomorph tetrapods from the Late Carboniferous of western North America. It includes two species: the type species Limnoscelis paludis from New Mexico, and Limnoscelis dynatis from Colorado, both of which are thought to have lived concurrently. No specimens of Limnoscelis are known from outside of North America. Limnoscelis was carnivorous, and likely semiaquatic, though it may have spent a significant portion of its life on land. Limnoscelis had a combination of derived amphibian and primitive reptilian features, and its placement relative to Amniota has significant implications regarding the origins of the first amniotes.

<i>Echinerpeton</i> Extinct genus of synapsids

Echinerpeton is an extinct genus of synapsid, including the single species Echinerpeton intermedium from the Late Carboniferous of Nova Scotia, Canada. The name means 'spiny lizard' (Greek). Along with its contemporary Archaeothyris, Echinerpeton is the oldest known synapsid, having lived around 308 million years ago. It is known from six small, fragmentary fossils, which were found in an outcrop of the Morien Group near the town of Florence. The most complete specimen preserves articulated vertebrae with high neural spines, indicating that Echinerpeton was a sail-backed synapsid like the better known Dimetrodon, Sphenacodon, and Edaphosaurus. However, the relationship of Echinerpeton to these other forms is unclear, and its phylogenetic placement among basal synapsids remains uncertain.

<i>Xyrospondylus</i> Extinct genus of synapsids

Xyrospondylus is an extinct genus of non-mammalian synapsids belonging to the Edaphosauridae. The type species, X. ecordi, was named in 1982; it was originally named as a species of Edaphosaurus in 1957.

<i>Ianthodon</i> Extinct genus of synapsids

Ianthodon is an extinct genus of basal haptodontiform synapsids from the Late Carboniferous about 304 million years ago. The taxon was discovered and named by Kissel & Reisz in 2004. The only species in the taxon, Ianthodon schultzei, was found by separating it from a block that also contained the remains of Petrolacosaurus and Haptodus. The evolutionary significance of the taxon wasn't realized until a publication in 2015. The fossil of this organism was discovered in Garnett, Kansas.

<i>Heleosaurus</i> Extinct genus of tetrapods

Heleosarus scholtzi is an extinct species of basal synapsids, known as pelycosaurs, in the family of Varanopidae during the middle Permian. At first H. scholtzi was mistakenly classified as a diapsid. Members of this family were carnivorous and had dermal armor, and somewhat resembled monitor lizards. This family was the most geologically long lived, widespread, and diverse group of early amniotes. To date only two fossils have been found in the rocks of South Africa. One of these fossils is an aggregation of five individuals.

<i>Fedexia</i> Extinct genus of amphibians

Fedexia is an extinct genus of carnivorous temnospondyl within the family Trematopidae. It lived 300 million years ago during the late Carboniferous period. It is estimated to have been 2 feet (0.61 m) long, and likely resembled a salamander. Fedexia is known from a single skull found in Moon Township, Pennsylvania. It is named after the shipping service FedEx, which owned the land where the holotype specimen was first found.

Euconcordia is an extinct genus of Late Carboniferous captorhinid known from Greenwood County, Kansas of the United States.

<i>Gordodon</i> Extinct genus of edaphosaurid synapsids

Gordodon is an extinct genus of non-mammalian synapsid that lived during the Early Permian of what is now Otero County, New Mexico. It was a member of the herbivorous sail-backed family Edaphosauridae and contains only a single species, the type species G. kraineri. Gordodon is unusual among early synapsids for its teeth, which were arranged similarly to those of modern mammals and unlike the simple, uniform lizard-like teeth of other early herbivorous synapsids. Gordodon had large incisor-like teeth at the front, followed by a prominent gap between them and a short row of peg-like teeth at the back. Gordodon was also relatively long-necked for an early synapsid, with elongated and gracile vertebrae in its neck and back. Like other edaphosaurids, Gordodon had a tall sail on its back made from the bony neural spines of its vertebrae. The spines also had bony knobs on them, a common trait of edaphosaurids, but the knobs of Gordodon are also unique for being more slender, thorn-like and randomly arranged along the spines. It is estimated to have been rather small at 1 m in length excluding the tail and 34 kg (75 lb) in weight.

<i>Kenomagnathus</i> Extinct genus of synapsids

Kenomagnathus is a genus of synapsid belonging to the Sphenacodontia, which lived during the Pennsylvanian subperiod of the Carboniferous in what is now Garnett, Kansas, United States. It contains one species, Kenomagnathus scottae, based on a specimen consisting of the maxilla and lacrimal bones of the skull, which was catalogued as ROM 43608 and originally classified as belonging to "Haptodus" garnettensis. Frederik Spindler named it as a new genus in 2020.

References

  1. T.S. Kemp (2005) The origin and evolution of mammals p.24.
  2. 1 2 Robert R. Reisz and David S. Berman (1986). "Ianthasaurus hardestii n. sp., a primitive edaphosaur (Reptilia, Pelycosauria) from the Upper Pennsylvanian Rock Lake Shale near Garnett, Kansas". Canadian Journal of Earth Sciences. 23 (1): 77–91. Bibcode:1986CaJES..23...77R. doi:10.1139/e86-008.
  3. "Ianthasaurus". Paleobiology Database. Retrieved December 11, 2007.