Hauffiopteryx Temporal range: Early Jurassic, | |
---|---|
Fossil of H. typicus | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Reptilia |
Order: | † Ichthyosauria |
Node: | † Parvipelvia |
Genus: | † Hauffiopteryx Maisch, 2008 |
Type species | |
†Hauffiopteryx typicus (von Huene, 1931 [originally Stenopterygius typicus]) | |
Other species | |
| |
Synonyms | |
|
Hauffiopteryx is an extinct genus of ichthyosaur known from Germany, Luxembourg, Switzerland and Somerset of the United Kingdom. [2] [3] [4] Two species are known: H. typicus and H. altera.
Hauffiopteryx was first described by Michael W. Maisch on the basis of some specimens that previously referred to Stenopterygius hauffianus . Maisch found that the lectotype of S. hauffianus can be determined as Stenopterygius cf. S. quadriscissus at best, and therefore this species should be considered a nomen dubium. He also found out that most specimens previously referred to S. hauffianus can be referred to S. quadriscissus, while the rest belongs to a highly distinctive new taxon that can't be referred to any valid species of Stenopterygius. [2]
Hauffiopteryx is known from the lectotype GPIT 1491/4, articulated complete skeleton which preserved the skull and some soft tissues. The animal is about 1.93 m (6.3 ft) in length. It was collected from the Harpoceras elegantulum-exaratum ammonoid subzones (more specifically Lias ε II4), Harpoceras falcifer zone, of the famous Posidonien-Schiefer lagerstätte (Posidonia Shale) of Holzmaden, dating to the early Toarcian stage of the Early Jurassic, about 182 million years ago. Referred specimens from Holzmaden, Germany and Dudelange, Luxembourg include MHH '9', WAT 1, SMNS 51552, SMNS 80225 and probably the poorly preserved SMNS 81965. They were collected from the Harpoceras semicelatum-elegantulum-exaratum ammonoid subzones (Lias ε II1-5, about 182.7-181.8 mya), Harpoceras tenuicostatum-falcifer zones, of the Posidonia Shale. [2]
Additional materials were described by Hannah Caine and Michael J. Benton in 2011, from the early Toarcian of Strawberry Bank, Ilminster of England. The specimens are all juveniles or infants which preserved almost complete skeletons and some skulls. They include BRLSI M1399 (which was described earlier by Maisch), BRLSI M1400, BRLSI M1401, BRLSI M1403, BRLSI M1404 and BRLSI M1406. [3]
Hauffiopteryx was originally recognized by Friedrich von Huene in 1931 as a subspecies of S. hauffianus and named Stenopterygius hauffianus typica. Michael W. Maisch in 2008 elevated it to specific rank and reassigned to its own genus, Hauffiopteryx. The type species is therefore Hauffiopteryx typicus. The generic name honors the Hauff family from Holzmaden, for their generation-long work to increase the knowledge on the Posidonia Shale and its fauna, especially the ichthyosaurs, and pteryx (πτερυξ), Greek for "fin" or "wing". The specific name means typical. [2] H. altera comes from the Latin word meaning "different from" or "other" due to the differences between it and H. typicus. [1]
Hauffiopteryx is a relatively small ichthyosaur, reaching 2–3 m (6.6–9.8 ft) in length. [1] [3]
The snout of Hauffiopteryx is short, but also very thin, tapering to a point. [3] [1] The outer surface of the tooth crowns is smooth, [1] and the back teeth are larger than those in front. [3] The upper jaw is slightly longer than the lower jaw, though this overbite is not carried to the extreme seen in Excalibosaurus and Eurhinosaurus . [3] [1] The nasals form the majority of the snout's midline, rather than the premaxillae (upper tooth-bearing bones). In H. altera, the tallest points of the maxillae (rear upper tooth-bearing bones) are positioned behind the external nares (openings that housed the nostrils), in contrast to H. typicus, where the tallest points are instead located beneath these openings. Part of the borders of the external nares are formed by the prefrontals (paired bones situated on the upper edges of the eye sockets). In H. altera, this configuration blocks the lacrimals (paired bones in front of the eye sockets) from forming part of the external nares, whereas the lacrimals do reach the external nares in H. typicus. A further difference between the two species lies in the shape of their lacrimals; in H. typicus, they are triradiate, while those of H. altera are massive and triangular. [1]
The orbits (eye sockets) of H. typicus are especially large and circular. In front of the orbits, the nasals of H. typicus curve upwards. The nasals extend further back in H. altera than in H. typicus, [1] though the nasals of Hauffiopteryx do not touch the parietals (a pair of skull roof bones). [3] Externally, the prefrontals have greater surface area than the postfrontals, especially so in H. altera. [1] The frontals (a pair of skull roof bones) form most of the border of the pineal foramen, a small opening on the midline of the skull. [3] Instead of being in line with the front edges of the supratemporal fenestrae (paired openings on the top of the skull's rear), the foramen is instead located in front of them. The supratemporal fenestrae themselves are rounded and small. The supratemporals (paired skull roof bones) have wavy edges. [1] Behind the orbits, the skull is short from front to back, with the cheek region deflected so that it faces backwards. The rear face basioccipital (braincase bone to which the vertebral column attaches) bears a considerable amount of surface which is not involved in the joint between the skull and the spine. [3]
In 2011, Caine and Benton stated that Hauffiopteryx has fewer than 46 vertebrae in front of its hips (presacral vertebrae) and typically over 34 but under 39 between its hips and the bend in its tail. [3] Maxwell and Cortés in 2020 described the lectotype as having 45 or 46 presacral vertebrae and a total of 81 vertebrae before the bend in the tail (preflexural vertebrae), with this bend composed of three vertebrae followed by more than 55 postflexural vertebrae. The upper ends of the dorsal ribs (those in the trunk region) are strongly forked, making them double-headed. Gastralia (belly ribs) are present along the underside of the trunk. This series of elements reaches far back, all the way to the level of the 35th vertebra. [1]
The scapulae (shoulder blades) of Hauffiopteryx have wide lower ends due to their front margins extending forwards. The front edge of each coracoid (shoulder bones located below the scapulae) is concave. No space is enclosed between the humeri (upper arm bones) and the radii and ulnae (lower arm bones), being tightly packed together. This is also the case for the other bones in the upper parts of the limbs, forming a mosaic-like pattern. [1] Each forelimb contains four main digits, and the front edge of the limb consists of some elements with indentations on their front edges. The lower pelvic bones (the pubic bones and ischia) are narrow and pillar-shaped. Unusually, the ends of these bones which form the hip socket are fused together, but the bones markedly diverge away from the socket. The thin femora (thighbones) each bear a strong site for the articulation of the fibula (rear shin bone). The fibulae are also much larger than the tibiae (front shin bones). While the front edges of the hindlimbs contain some notched elements like the forelimbs, there are only three main digits in each rear limb. [3] [1] These digits closely approach each other towards the tip of the limb. [1]
Both the original description by Maisch and the redescription of the English specimens found that Hauffiopteryx might be either a basalmost member of Eurhinosauria or a basalmost member of Thunnosauria (which is an equivalent position to a basalmost member of Stenopterygiidae sensu Maisch [2008] with exclusion of Ichthyosaurus ). [3] [2]
Ichthyosauria is an order of large extinct marine reptiles sometimes referred to as "ichthyosaurs", although the term is also used for wider clades in which the order resides.
Temnodontosaurus is an extinct genus of ichthyosaur from the Early Jurassic period. They lived between 200 and 175 million years ago (Hettangian-Toarcian) in what is now Western Europe and possibly other countries including Switzerland and Chile. It lived in the deeper areas of the open ocean. University of Bristol paleontologist Jeremy Martin described the genus Temnodontosaurus as "one of the most ecologically disparate genera of ichthyosaurs," although the number of valid Temnodontosaurus species has varied over the years.
Stenopterygius is an extinct genus of thunnosaur ichthyosaur known from Europe.
Eurhinosaurus is an extinct genus of ichthyosaur from the Early Jurassic (Toarcian), ranging between 183 and 175 million years. Fossils of the aquatic reptile have been found in Western Europe. They used to live in the deep, open sea area. Eurhinosaurus was a large genus of ichthyosaurs. An adult individual could reach up to 7 metres (23 ft) in length.
Aegirosaurus is an extinct genus of platypterygiine ophthalmosaurid ichthyosaurs known from the late Jurassic and early Cretaceous of Europe. It was originally named as a species of Ichthyosaurus.
Chaohusaurus is an extinct genus of basal ichthyosauriform, depending on definition possibly ichthyosaur, from the Early Triassic of Chaohu and Yuanan, China.
Chacaicosaurus is a genus of neoichthyosaurian ichthyosaur known from the Middle Jurassic of Argentina. The single known specimen of this genus was excavated from the Los Molles Formation in Neuquén Province, and is housed at the Museo Olsacher under the specimen number MOZ 5803. This specimen consists of a skull, forelimb, some vertebrae, and some additional postcranial elements. The genus was named by Marta Fernández in 1994, and contains a single species, Chacaicosaurus cayi, making it the first named distinctive ichthyosaur from the Bajocian stage. It is a medium-sized ichthyosaur with a very long snout, which bears a ridge running along each side. The forelimbs of Chacaicosaurus are small and contain four main digits.
Protoichthyosaurus is a genus of ichthyosaur from the early Jurassic of southern England and possibly Switzerland. Two species are known, P. prostaxalis—the type species, named by Appleby in 1979—and P. applebyi. A third species, P. prosostealis, was named by Appleby, but it was removed from the genus in 2017 due to its similarity to Ichthyosaurus. The genus Protoichthyosaurus was synonymized with Ichthyosaurus by Maisch and Hungerbuhler in 1997, and again by Maisch and Matzke in 2000. However, it was found to be distinct in 2017 by Dean Lomax and colleagues, who separated it from Ichthyosaurus on account of differences in the arrangement and shape of the carpal ossifications, as well as the absence of the fifth digit. The species most likely lived during the Hettangian stage, but may have lived as early as the Rhaetian and as late as the Sinemurian.
Besanosaurus is a extinct genus of Middle Triassic ichthyosaur from Monte San Giorgio of Italy and Switzerland, containing the single species B. leptorhynchus. Besanosaurus was named by Cristiano Dal Sasso and Giovanni Pinna in 1996, based on the nearly complete flattened skeleton BES SC 999, the holotype specimen. This skeleton is preserved across multiple thin rock slabs spanning 3.5 by 4 metres when assembled and took thousands of hours to prepare. Additional specimens from Monte San Giorgio that have previously been considered separate genera, including a partial skull named Mikadocephalus and a well-preserved, largely complete skeleton, have been reinterpreted as additional specimens of Besanosaurus. Putative specimens of Besanosaurus have been discovered in the Norwegian archipelago of Svalbard and Germany, although their attribution to this genus remains disputed.
Callawayia is an extinct genus of ichthyosaur. It contains the species Callawayia neoscapularis.
Guizhouichthyosaurus is an extinct genus of ichthyosaur which is known primarily from the Xiaowa Formation of the lower Carnian stage of the Late Triassic in southwest China. The type species of this genus is Guizhouichthyosaurus tangae, of which multiple skeletons are known. It has been reassigned as a species of the genus Shastasaurus in the past, though it has since been considered distinct. The ichthyosaurs Cymbospondylus asiaticus, named in 2002, and Panjiangsaurus epicharis, named in 2003, are junior synonyms of G. tangae. The genus is also known from the Ladinian-aged Middle Triassic Zhuganpo Formation; additionally, the species "Callawayia" wollongangense may belong to Guizhouichthyosaurus.
Parvinatator, from Latin, “parvus” little and “natator” swimmer, is an extinct genus of small ichthyopterygian marine reptile that lived during the Early to Middle Triassic. Its fossils have been found in British Columbia, Canada.
Suevoleviathan is an extinct genus of primitive ichthyosaur found in the Early Jurassic (Toarcian) of Holzmaden, Germany.
Thaisaurus is an extinct genus of ichthyopterygian marine reptile that lived during the Spathian. Fossils have been found in Thailand.
Toretocnemus is an extinct genus of ichthyosaur. Its remains have been found in California, United States, in Triassic layers of the Carnian Hosselkus Limestone.
Wimanius is a genus of ichthyosaur from the Middle Triassic of Switzerland, containing a single species, Wimanius odontopalatus. It was described by Michael Maisch and Andreas Matzke in 1998 based on an incomplete skull from Monte San Giorgio, a mountain on the Swiss-Italian border. Wimanius possesses teeth on its palate, though whether they were located on the palatine or pterygoid is disputed. Other features of Wimanius include a large orbit and jugals with two rami of similar lengths. Different phylogenetic placements of Wimanius have been recovered by different studies, including it being a mixosaurid relative or a merriamosaur, and a monotypic family, Wimaniidae has been named for it. However, its validity has also been questioned, and synonymy with various other genera has been proposed. The only specimen of Wimanius come from the Besano Formation. During the Anisian, this region was a lagoon populated by a wide variety of marine life, including a variety of other ichthyosaurs.
Athabascasaurus is an extinct genus of platypterygiine ophthalmosaurid ichthyosaur known from Alberta, Canada.
Mixosauridae was an early group of ichthyosaurs, living between 247.2 and 235 million years ago, during the Triassic period. Fossils of mixosaurs have been found all over the world: China, Timor, Indonesia, Italy, Germany, Spitsbergen, Switzerland, Svalbard, Canada, Alaska, and Nevada.
This timeline of ichthyosaur research is a chronological listing of events in the history of paleontology focused on the ichthyosauromorphs, a group of secondarily aquatic marine reptiles whose later members superficially resembled dolphins, sharks, or swordfish. Scientists have documented ichthyosaur fossils at least as far back as the late 17th century. At that time, a scholar named Edward Lhuyd published a book on British fossils that misattributed some ichthyosaur vertebrae to actual fishes; their true nature was not recognized until the 19th century. In 1811, a boy named Joseph Anning discovered the first ichthyosaur fossils that would come to be scientifically recognized as such. His sister Mary would later find the rest of its skeleton and would go on to become a respected fossil collector and paleontologist in her own right.
Kyhytysuka is an extinct genus of ophthalmosaurian ichthyosaur from Early Cretaceous Colombia. The animal was previously assigned to the genus Platypterygius, but given its own genus in 2021. Kyhytysuka was a mid-sized ophthalmosaurian with heterodont dentition and several adaptations suggesting that it was a macropredatory vertebrate hunter living in shallow waters. It contains a single species, Kyhytysuka sachicarum.