Ichthyosauria Fossil range: Middle Triassic - Late Cretaceous
Ichthyosauria, Holzmaden, Museum Wiesbaden
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Sauropsida Subclass: Diapsida? Superorder: Ichthyopterygia Order: Ichthyosauria Blainville, 1835
Families
Ichthyosauridae Leptonectidae Mixosauridae Ophthalmosauridae Shastasauridae Stenopterygiidae Teretocnemidae

Ichthyosaurs (Greek for 'fish lizard' - ιχθυς meaning 'fish' and σαυρος meaning 'lizard') were giant marine reptiles that resembled fish and dolphins. The Middle Triassic (also known as Muschelkalk) is the second of three epochs of the Triassic period. Late Cretaceous (100mya - 65mya refers to the second half of the Cretaceous Period, named after the famous white Chalk cliffs of southern England Chordates ( Phylum Chordata) are a group of Animals that includes the Vertebrates together with several closely related Invertebrates Reptiles, or members of the class Reptilia are air-breathing Cold-blooded Vertebrates that have skin covered in scales as opposed to hair or feathers Diapsids ("two arches" are a group of Reptiles that developed two holes ( Temporal fenestra) in each side of their Skulls about 300 Million Ichthyopterygia ("fish flippers" was a designation introduced by Sir Richard Owen in 1840 to designate the Jurassic Ichthyosaurs that were known at Henri Marie Ducrotay de Blainville ( September 12, 1777 - May 1, 1850) was a French Zoologist and Anatomist. Year 1835 ( MDCCCXXXV) was a Common year starting on Thursday (link will display the full calendar of the Gregorian Calendar (or a Common In Biological classification, family ( Latin Ichthyosaurus (derived from Greek ιχθυς / ichthyos meaning 'fish' and σαυρος / sauros meaning 'lizard' is Mixosaurus is an Extinct Genus of Ichthyosaur. It was about 1 meter (3 ft 4 in long Ophthalmosauridae were a family of Ichthyosaurs that lived from the Jurassic to the Cretaceous period The shastasaurs were an early group of Ichthyosaurs, living 230-210 million years ago in the Triassic period Stenopterygidae are a family of the Ichthyosauria, a group of extinct marine reptiles that superficially resemble fish Teretocnemidae were a group of Ichthyosaurs that lived from the Late Jurassic period The Ancient Greek language is the historical stage in the development of the Hellenic language family spanning the Archaic (c Reptiles, or members of the class Reptilia are air-breathing Cold-blooded Vertebrates that have skin covered in scales as opposed to hair or feathers Ichthyosaurs thrived during much of the Mesozoic era; based on fossil evidence, they first appeared approximately 230 million years ago (Mya) and disappeared about 90 million years ago, about 25 million years before the dinosaurs became extinct. The Mesozoic Era is one of three geologic eras of the Phanerozoic eon. FOSSIL is a standard protocol for allowing serial communication for Telecommunications programs under the DOS Operating system. Annum is one form of the Latin noun meaning Year, not a form normally used for derivatives in modern languages the accusative singular In Astronomy, Geology, and Paleontology, mya or " mya " is an abbreviation for "million years ago". During the middle Triassic Period, ichthyosaurs evolved from as-yet unidentified land reptiles that moved back into the water, in a development parallel to that of modern-day dolphins and whales. The Triassic is a geologic period and system that extends from about 251 to 199 Ma (million years ago Dolphins are Marine mammals that are closely related to Whales and Porpoises There are almost forty species of dolphin in seventeen genera. Whales are marine mammals which are neither Dolphins (ie members of the families Delphinidae or Platanistoidae) nor Porpoises Orcas They were particularly abundant in the Jurassic Period, until they were replaced as the top aquatic predators by plesiosaurs in the Cretaceous Period. The Jurassic is a geologic period and system that extends from about Ma (million years ago to  Ma that is from the end of the Triassic to the beginning Plesiosaurs (ˈpliːziəˌsɔɹ ( Greek: plesios/πλησιος meaning 'near' or 'close to' and sauros/σαυρος meaning The Cretaceous (kriːˈteɪʃəs, usually abbreviated 'K' for its German translation "Kreide" is a geologic period and system, reaching from the end of They belong to the order known as Ichthyosauria or Ichthyopterygia ('fish flippers' - a designation introduced by Sir Richard Owen in 1840, although the term is now used more for the parent clade of the Ichthyosauria). Sir Richard Owen KCB ( Lancaster, July 20 1804 &ndash December 18 1892) was an English Biologist

Description

Ichthyosaurs averaged 2 to 4 meters in length (although a few were smaller, and some species grew much larger), with a porpoise-like head and a long, toothed snout. Porpoises are Small Cetaceans of the Family Phocoenidae; they are related to Whales and Dolphins They are distinct from dolphins Built for speed, like modern tuna, some ichthyosaurs appear also to have been deep divers, like some modern whales (Motani, 2000). Tuna, are several Species of ocean-dwelling Fish in the family Scombridae, mostly in the genus Thunnus. It has been estimated that ichthyosaurs could swim at speeds up to 40 km/h (25 mph). Similar to modern cetaceans such as whales and dolphins, they were air-breathing and also were viviparous (some adult fossils have even been found containing fetuses). The Order Cetacea (sɪˈteɪʃiə L cetus, whale includes Whales Dolphins and Porpoises Cetus is A viviparous Animal is an animal employing vivipary: the embryo develops inside the body of the mother as opposed to outside in an egg ( Ovipary Although they were reptiles and descended from egg-laying ancestors, viviparity is not as unexpected as it first appears. All air-breathing marine creatures must either come ashore to lay eggs, like turtles and some sea snakes, or else give birth to live young in surface waters, like whales and dolphins. Given their streamlined bodies, heavily adapted for fast swimming, it would have been difficult for ichthyosaurs to scramble successfully onto land to lay eggs. Fluid flow is described in general by a Vector field in three (for steady flows or four (for non-steady flows including time dimensions

Historical Ichthyosaur illustration, 1863.

According to weight estimates by Ryosuke Motani [1] a 2. 4 meter (8 ft) Stenopterygius weighed around 163 to 168 kg (360 to 370 lb), whilst a 4. Stenopterygius is an extinct genus of Ichthyosaur from the Early to Middle Jurassic ( Toarcian - Aalenian) from Europe 0 meter (13 ft) Ophthalmosaurus icenicus weighed 930 to 950 kg (about a ton). Ophthalmosaurus (meaning “eye lizard” in Greek was an Ichthyosaur of the Middle to Late Jurassic period (165 to 145 million years ago

Although ichthyosaurs looked like fish, they were not. Biologist Stephen Jay Gould said the ichthyosaur was his favorite example of convergent evolution, where similarities of structure are analogous not homologous, for this group:

Drawing of an Ichthyosaur skeleton. Stephen Jay Gould (September 10 1941 &ndash May 20 2002 was a prominent American paleontologist, evolutionary biologist, and historian of science Convergent evolution describes the acquisition of the same biological trait in unrelated lineages Analogy is both the cognitive process of transferring Information from a particular subject (the analogue or source to another particular subject (the target and In Evolutionary biology, homology has come to mean any similarity between characters that is due to their shared ancestry.

Fossil of a young Ichthyosaur from the zoological museum of Hamburg.

Ichthyosaur 'paddle' (Charmouth Heritage Coast Centre). Charmouth Heritage Coast Centre is based in the upstairs floor of a long-disused cement factory on the foreshore of Charmouth in Dorset, England.

converged so strongly on fishes that it actually evolved a dorsal fin and tail in just the right place and with just the right hydrological design. A dorsal fin is a Fin located on the backs of some Fishes Whales Dolphins and Porpoises as well as the (extinct These structures are all the more remarkable because they evolved from nothing — the ancestral terrestrial reptile had no hump on its back or blade on its tail to serve as a precursor.

Temnodontosaurus platyodon

In fact the earliest reconstructions of ichthyosaurs omitted the dorsal fin, which had no hard skeletal structure, until finely-preserved specimens recovered in the 1890s from the Holzmaden lagerstätten in Germany revealed traces of the fin. Temnodontosaurus was an Ichthyosaur from the Early Jurassic, some 198 and 185 milion years ago ( Hettangian - Toarcian) in Europe The 1890s were sometimes referred to as the " Mauve Decade" because William Henry Perkin 's aniline dye allowed the widespread use of that Holzmaden is a town in Baden-Württemberg, Germany that lies between Stuttgart and Ulm. A Lagerstätte ( German; literally place of storage; plural Lagerstätten) is a sedimentary deposit that exhibits extraordinary fossil Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe. Unique conditions permitted the preservation of soft tissue impressions.

Ichthyosaurs had fin-like limbs, which were possibly used for stabilisation and directional control, rather than propulsion, which would have come from the large shark-like tail. The tail was bi-lobed, with the lower lobe being supported by the caudal vertebral column, which was "kinked" ventrally to follow the contours of the ventral lobe.

Apart from the obvious similarities to fish, the ichthyosaurs also shared parallel developmental features with dolphins. Dolphins are Marine mammals that are closely related to Whales and Porpoises There are almost forty species of dolphin in seventeen genera. This gave them a broadly similar appearance, possibly implied similar activity and presumably placed them broadly in a similar ecological niche.

For their food, many of the fish-shaped ichthyosaurs relied heavily on ancient cephalopod kin of squids called belemnites. The cephalopods ( Greek plural (kephalópoda "head-feet" are the Mollusc class Cephalopoda characterized by Squid are marine Cephalopods of the order Teuthida, which comprises around 300 species Belemnites (or belemnoids are an extinct group of marine Cephalopod, very similar in many ways to the modern Squid and closely related to the modern Cuttlefish Some early ichthyosaurs had teeth adapted for crushing shellfish. Shellfish is a Culinary and Fisheries term for those aquatic Invertebrate animals that are used as Food: various species of molluscs They also most likely fed on fish, and a few of the larger species had heavy jaws and teeth that indicated they fed on smaller reptiles. Ichthyosaurs ranged so widely in size, and survived for so long, that they are likely to have had a wide range of prey. Typical ichthyosaurs have very large eyes, protected within a bony ring, suggesting that they may have hunted at night. Sclerotic rings are rings of Bone found in the Eyes of several groups of Vertebrate animals except for Mammals and Crocodilians They

History of discoveries

Ichthyosaur mounted skeleton (Charmouth Heritage Coast Centre). Charmouth Heritage Coast Centre is based in the upstairs floor of a long-disused cement factory on the foreshore of Charmouth in Dorset, England.

The genus had first been described in 1699 from fossil fragments discovered in Wales.

The first fossil vertebrae were published twice in 1708 as tangible mementos of the Universal Deluge. FOSSIL is a standard protocol for allowing serial communication for Telecommunications programs under the DOS Operating system. A vertebra (plural vertebrae) is an individual Irregular bone in the spinal or Vertebral column ( aka ischis a flexuous and flexible column Year 1708 ( MDCCVIII) was a Leap year starting on Sunday (link will display the full calendar of the Gregorian calendar (or a The story of a Great Flood (also known as the Deluge) sent by a Deity or deities to destroy Civilization as an act of Divine retribution is a The first complete ichthyosaur fossil was found in 1811 by Mary Anning in Lyme Regis, along what is now called the Jurassic Coast. Year 1811 ( MDCCCXI) was a Common year starting on Tuesday (link will display the full calendar of the Gregorian calendar (or a Common year Mary Anning ( May 21, 1799 &ndash March 9, 1847) was an early British Fossil collector and paleontologist. Lyme Regis (ˌlaɪmˈriːdʒɪs is a coastal town in West Dorset, England, situated 25 Miles west of Dorchester and east of Exeter The Jurassic Coast is a World Heritage Site on the English Channel coast of southern England. She subsequently discovered three separate species.

In 1905, the Saurian Expedition led by John C. Merriam of the University of California and financed by Annie Alexander, found 25 specimens in central Nevada, which during the Triassic was under a shallow ocean. Year 1905 ( MCMV) was a Common year starting on Sunday (link will display full calendar of the Gregorian calendar (or a Common year starting The Saurian Expedition of 1905 was a noted paleontological research mission in northern Nevada in the United States. This is the article about John Campbell Merriam the American paleontologist The University of California ( UC) is a Public university system in the state of California. Annie Montague Alexander (1867-1950 was an American Philanthropist and paleontological collector Nevada ( is a state located in the western region of the United States of America. Several of the specimens are now in the collection of the University of California Museum of Paleontology. The University of California ( UC) is a Public university system in the state of California. Other specimens are embedded in the rock and visible at Berlin-Ichthyosaur State Park in Nye County. The Berlin-Ichthyosaur State Park is a State park of the US state of Nevada. Nye County is a County located in the US state of Nevada. As of the 2000 census, the population was 32485 In 1977 the Triassic ichthyosaur Shonisaurus became the State Fossil of Nevada. Also 1977 (album by Ash. Year 1977 ( MCMLXXVII) was a Common year starting on Saturday (link displays Most American states have made a state fossil designation in many cases during the 1980s. Nevada is the only state to possess a complete skeleton, 55 ft (17 m) of this extinct marine reptile. In 1992, Canadian ichthyologist Dr. Elizabeth Nicholls (Curator of Marine Reptiles at the Royal Tyrrell {"tur ell"} Museum) uncovered the largest fossil specimen ever, a 23m (75')-long example.

Evolutionary history

A skeleton at the American Museum of Natural HIstory.

The earliest ichthyosaurs, looking more like finned lizards than the familiar fish or dolphin forms, are known from the Early and Early-Middle (Olenekian and Anisian) Triassic strata of Canada, China, Japan, and Spitsbergen in Norway. Ichthyopterygia ("fish flippers" was a designation introduced by Sir Richard Owen in 1840 to designate the Jurassic Ichthyosaurs that were known at The Olenekian (also known as the Yongningzhenian) is a stage of the Early Triassic epoch. In the Geologic timescale, the Anisian is the age of the Middle Triassic epoch and lasted from 245 million years ago until 237 million years The Triassic is a geologic period and system that extends from about 251 to 199 Ma (million years ago Country to "Dominion of Canada" or "Canadian Federation" or anything else please read the Talk Page China ( Wade-Giles ( Mandarin) Chung¹kuo² is a cultural region, an ancient Civilization, and depending on perspective a National For a topic outline on this subject see List of basic Japan topics. Spitsbergen (formerly known as West Spitsbergen, and sometimes misspelled Spitzbergen) is a Norwegian island the largest Island of the Norway ( Norwegian: Norge ( Bokmål) or Noreg ( Nynorsk) officially the Kingdom of Norway, is a Constitutional These primitive forms included the genera Chaohusaurus, Grippia, and Utatsusaurus. Chaohusaurus geishanensis (' Geisha lizard of Chaohu' was an Ichthyosaur, an extinct fish-like marine reptile from the Early Triassic of Chaohu China Grippia is a Genus of Ichthyosaur, an Extinct group of reptiles that resembled Dolphins Fossils have been found along the coasts Utatsusaurus is the earliest-known form of an Ichthyopterygian (the group of marine reptiles that includes the Ichthyosaurs) which lived in the early

Grippia longirostris from early Triassic of Spitsbergen

These very early proto-ichthyosaurs, which are now classified as Ichthyopterygia rather than as ichthyosaurs proper (Motani 1997, Motani et al. Grippia is a Genus of Ichthyosaur, an Extinct group of reptiles that resembled Dolphins Fossils have been found along the coasts Ichthyopterygia ("fish flippers" was a designation introduced by Sir Richard Owen in 1840 to designate the Jurassic Ichthyosaurs that were known at 1998), quickly gave rise to true ichthyosaurs sometime in the latest Early Triassic or earliest Middle Triassic. These later diversified into a variety of forms, including the sea-serpent like Cymbospondylus, which reached 10 meters, and smaller more typical forms like Mixosaurus. Cymbospondylus was a basal early Ichthyosaur that lived in the middle of the Triassic period Mixosaurus is an Extinct Genus of Ichthyosaur. It was about 1 meter (3 ft 4 in long By the Late Triassic, ichthyosaurs consisted of both classic Shastasauria and more advanced, "dolphin"-like Euichthyosauria (Californosaurus, Toretocnemus) and Parvipelvia (Hudsonelpidia, Macgowania). The Late Triassic (also known as Upper Triassic, or Keuper) is the third and final of three epochs of the Triassic period. Californosaurus perrini ('Perrin's California lizard' was an Ichthyosaur, an extinct fish-like marine reptile from the Lower Hosselkus Limestone ( Carnian Experts disagree over whether these represent an evolutionary continum, with the less specialised shastosaurs a paraphyletic grade that was evolving into the more advanced forms (Maisch and Matzke 2000), or whether the two were separate clades that evolved from a common ancestor earlier on (Nicholls and Manabe 2001). In Phylogenetics, a group of organisms is said to be paraphyletic if the group contains its most recent common ancestor but does not contain all A clade is a taxonomic group comprising a single Common ancestor and all the descendants of that ancestor

During the Carnian and Norian, shastosaurs reached huge sizes. The Carnian (less commonly Karnian) is the lowermost stage of the Upper Triassic series (or earliest age of the Late Triassic The Norian Stage was a portion of the Triassic Geological period. Shonisaurus popularis, known from a number of specimens from the Carnian of Nevada, was 15 meters long. Shonisaurus was the largest Genus of Ichthyosaur that has yet been found Norian shonisaurs are known from both sides of the Pacific. Himalayasaurus tibetensis and Tibetosaurus (probably a synonym) have been found in Tibet. Definitions of Tibet See also Definitions of Tibet Name In English The English word Tibet, like the word for Tibet in most European These large (10 to 15 meters long) ichthyosaurs probably belong to the same genus as Shonisaurus (Motani et al, 1999; Lucas, 2001, pp. 117-119). While the gigantic Shonisaurus sikanniensis, whose remains were found in the Pardonet formation of British Columbia by Elizabeth Nicholls, reached as much as 21 meters in length - the largest marine reptile known to date.

These giants (along with their smaller cousins) seemed to have disappeared at the end of the Norian. Rhaetian (latest Triassic) ichthyosaurs are known from England, and these are very similar to those of the Early Jurassic. See Raetians for the Alpine people of antiquity See Romansh language for the Rhaetian language For general context see Jurassic. The Early Jurassic (in geology referred to as the Lower Jurassic, originally (and still in Europe the Like the dinosaurs, the ichthyosaurs and their contemporaries the plesiosaurs survived the end-Triassic extinction event, and immediately diversified to fill the vacant ecological niches of the earliest Jurassic.

A historical restoration of Ichthyosaurus by Heinrich Harder.

Platypterigius longmani

Yasykovia yasikovi from Upper Jurassic (Tithonian) of Volga region

The Early Jurassic, like the Late Triassic, was the heyday of the ichthyosaurs, which are represented by four families and a variety of species, ranging from one to ten meters in length. Platypterygius ('Flat wing (flipper' von Huene 1922 was an Ichthyosaur, an extinct group of reptiles that resembled dolphins of the family Ophthalmosauridae Genera include Eurhinosaurus, Ichthyosaurus, Leptonectes, Stenopterygius, and the large predator Temnodontosaurus, along with the persistently primitive Suevoleviathan, which was little changed from its Norian ancestors. Ichthyosaurus (derived from Greek ιχθυς / ichthyos meaning 'fish' and σαυρος / sauros meaning 'lizard' is Temnodontosaurus was an Ichthyosaur from the Early Jurassic, some 198 and 185 milion years ago ( Hettangian - Toarcian) in Europe All these animals were streamlined, dolphin-like forms, although the more primitive animals were perhaps more elongated than the advanced and compact Stenopterygius and Ichthyosaurus. Stenopterygius is an extinct genus of Ichthyosaur from the Early to Middle Jurassic ( Toarcian - Aalenian) from Europe Ichthyosaurus (derived from Greek ιχθυς / ichthyos meaning 'fish' and σαυρος / sauros meaning 'lizard' is

Ichthyosaurs were still common in the Middle Jurassic, but had now decreased in diversity. The Middle Jurassic, called the Dogger in the European system of classification is the second epoch of the Jurassic Period. All belonged to the single clade Ophthalmosauria. Represented by the 4 meter long Ophthalmosaurus and related genera, they were very similar to Ichthyosaurus, and had attained a perfect "tear-drop" streamlined form. Ophthalmosaurus (meaning “eye lizard” in Greek was an Ichthyosaur of the Middle to Late Jurassic period (165 to 145 million years ago The eyes of Ophthalmosaurus were huge, and it is likely that these animals hunted in dim and deep water (Motani 2000).

Ichthyosaurs seemed to decrease in diversity even further with the Cretaceous. The Cretaceous (kriːˈteɪʃəs, usually abbreviated 'K' for its German translation "Kreide" is a geologic period and system, reaching from the end of Only a single genus is known, Platypterygius, and although it had a worldwide distribution, there was little diversity species-wise. Platypterygius ('Flat wing (flipper' von Huene 1922 was an Ichthyosaur, an extinct group of reptiles that resembled dolphins of the family Ophthalmosauridae This last ichthyosaur genus became extinct during the Cenomanian-Turonian extinction event early in the Late Cretaceous (as did the pliosaurs). Oceanic anoxic events or Anoxic events occur when the Earth 's Oceans become completely depleted of oxygen (O2 below the surface levels The Pliosaurs ("more lizards" were marine reptiles from the Jurassic and Cretaceous Periods. Interestingly, less hydrodynamically efficient animals like mosasaurs and long-necked plesiosaurs flourished. Mosasaurs (from Latin Mosa meaning the ' Meuse river ' in the Netherlands and Greek sauros meaning 'lizard' were serpentine marine Plesiosaurs (ˈpliːziəˌsɔɹ ( Greek: plesios/πλησιος meaning 'near' or 'close to' and sauros/σαυρος meaning It could be that the ichthyosaurian over-specialisation was a contributing factor to their extinction, possibly being unable to 'keep up' with the fast swimming and highly evasive new teleost fishes, which had become dominant at this time, against which the sit-and-wait ambush strategies of the mosasaurs proved superior (Lingham-Soliar 1999). Teleostei is one of three infraclasses in class Actinopterygii, the ray-finned fishes

Taxonomy of species

• Order ICHTHYOSAURIA
• Family Mixosauridae
• Suborder Merriamosauriformes
  • Guanlingsaurus
  • (unranked) Merriamosauria
    • Family Shastasauridae
    • Cymbospondylus
    • Infraorder Euichthyosauria ("true ichthyosaurs")
      • Family Teretocnemidae
      • (Unranked) Parvipelvia ("small pelves")
        • Macgovania
        • Hudsonelpidia
        • Suevoleviathan
        • Temnodontosaurus
        • Family Leptonectidae
        • Infraorder Thunnosauria ("tuna lizards")
          • Family Stenopterygiidae
          • Family Ichthyosauridae
          • Family Ophthalmosauridae

In popular culture

• Ichthyosaurus is one of the prehistoric creatures mentioned in Jules Verne's book Journey to the Center of the Earth, in which it fights with a Plesiosaurus. Mixosaurus is an Extinct Genus of Ichthyosaur. It was about 1 meter (3 ft 4 in long The shastasaurs were an early group of Ichthyosaurs, living 230-210 million years ago in the Triassic period Cymbospondylus was a basal early Ichthyosaur that lived in the middle of the Triassic period Teretocnemidae were a group of Ichthyosaurs that lived from the Late Jurassic period Temnodontosaurus was an Ichthyosaur from the Early Jurassic, some 198 and 185 milion years ago ( Hettangian - Toarcian) in Europe Stenopterygidae are a family of the Ichthyosauria, a group of extinct marine reptiles that superficially resemble fish Ichthyosaurus (derived from Greek ιχθυς / ichthyos meaning 'fish' and σαυρος / sauros meaning 'lizard' is Ophthalmosauridae were a family of Ichthyosaurs that lived from the Jurassic to the Cretaceous period Jules Gabriel Verne ( February 8 1828 &ndash March 24 1905) was a French Author who pioneered the science-fiction A Journey to the Centre of the Earth (Voyage au centre de la Terre also translated as A Journey to the Interior of the Earth, is a classic 1864 Plesiosaurus (Greek πλησιος / plesios, near to + σαυρος / sauros, lizard was a large (about 3 to 5 meters long marine However, in the book it is described as being much, much larger than it was in reality. Ironically, in the book the Ichthyosaurus wins the fight against the Plesiosaurus when the Plesiosaurus replaced the Ichthyosaurs as top marine predators in the Cretaceous period. The Cretaceous (kriːˈteɪʃəs, usually abbreviated 'K' for its German translation "Kreide" is a geologic period and system, reaching from the end of

• The large aquatic monster from the video game Half-Life is named Ichthyosaur.

References

External links

• USMP Berkeley's ichthyosaur introduction
• Ryosuke Motani's detailed Ichthyosaur homepage, with vivid graphics
• Eureptilia: Ichthyosauria - Palaeos
• Ichthyosauria - cladogram (Mikko's Phylogeny Archive)
• Hauff Museum, Germany - exhibiting the finds of Holzmaden