Brachiosauridae is a clade of titanosauriform sauropod dinosaurs that includes the well-known Late Jurassic taxa Brachiosaurus and Giraffatitan. However, there is disagreement over the brachiosaurid affinities of most other taxa, and little consensus regarding the clade’s composition or inter-relationships.
Brachiosauridae has been defined as all titanosauriforms that are more closely related to Brachiosaurus than to Saltasaurus.It is one of the three main groups of the clade Titanosauriformes, which also includes the Euhelopodidae and the Titanosauria.
Brachiosaurids had long necks that enabled them to access the leaves of tall trees that other sauropods would have been unable to reach.In addition, they possessed thick spoon-shaped teeth which helped them to consume tough plants more efficiently than other sauropods.They have also been characterized by a few unique traits or synapomorphies; dorsal vertebrae with "rod-like" transverse processes and an ischium with an abbreviated pubic peduncle.

1. Sauroposeidon 2. Brachiosaurus 3. Giraffatitan 4. Ultrasaurus 5. Astrodon
Brachiosauridae consists of a paraphyletic array of Late Jurassic forms, with Europasaurus, Vouivria and Brachiosaurus recovered as successively more nested genera that lie outside of a clade comprising (Giraffatitan + Sonorasaurus) + (Lusotitan + (Cedarosaurus + Venenosaurus)). Abydosaurus forms an unresolved polytomy with the latter five taxa.The Early Cretaceous South American sauropod Padillasaurus was previously regarded as a brachiosaurid, but is here placed within Somphospondyli. A recent study contended that a number of characters used in a previous iteration of this data matrix are ‘biologically related’, and thus should be excluded from phylogenetic analysis.
Unambiguous brachiosaurid remains are known only from the USA, western Europe and Africa, and the clade spanned the Late Jurassic through to the late Albian/early Cenomanian, with the last known occurrences all from the USA. Regardless of whether their absence from the Cretaceous of Europe, as well as other regions entirely, reflects regional extinctions and genuine absences, or sampling artefacts, brachiosaurids appear to have become globally extinct by the earliest Late Cretaceous.

Breviparopus

Breviparopus (ichnotype B. taghbaloutensis) is the name given to an ichnogenus of dinosaur, having been made by an unknown genus of sauropod. As an ichnogenus, the taxon is represented by (and named for) a 90-metre (295 ft) long series of fossil tracks, or ichnites, found in the spring of 1979 in the Atlas Mountains of present-day Morocco. At the time, this area would have been part of the splitting Gondwana supercontinent.The animal that produced the Breviparopus tracks is rumored to be one of the largest dinosaurs, though its exact size has been the subject of much debate.
The combined length of the tracks of the foot and hand measured 115 centimetres (45 in), and they were 90 centimetres (35 in) in width. They are commonly dated to the Jurassic period (approximately 160–175 million years ago), though they are more likely from the early Cretaceous, roughly 130-120 million years ago.They were first described by Jean-Michel Dutuit and Achmed Ouazzou in 1980.
The size, weight, and even family tree of the animal that made Breviparopus tracks is unknown, but a great deal of speculation has arisen about this animal. Length estimates as great as 48 metres (157 ft) have been given in popular books such as Guinness World Records, though these were based on the misconception that the 115 centimetres (45 in) figure was based on a single footprint, not the combined length of the fore and hind feet.
In reality, the trackmakers of Breviparopus were likely somewhat smaller than this. The actual prints are 90 centimetres (35 in) wide and about as long. The feet were probably even larger than 90 centimetres (35 in) wide since the edges of the prints are collapsed. This would result in an animal roughly 34 to 37 metres (112 to 121 ft) long, assuming proportions similar to Giraffatitan.

Sauroposeidon

Sauroposeidon ( meaning "earthquake god lizard", after the Greek god Poseidon) is a genus of sauropod dinosaur known from several incomplete specimens including a bone bed and fossilized trackways that have been found in the American states of Oklahoma, Wyoming, and Texas. The fossils were found in rocks dating from near the end of the Early Cretaceous (Aptian-early Albian), a time when sauropod diversity in North America had greatly diminished. It was the last known North American sauropod prior to an absence of the group on the continent of roughly 40 million years that ended with the appearance of Alamosaurus during the Maastrichtian.
While the holotype remains were initially discovered in 1994, due to their unexpected age and unusual size they were initially misclassified as pieces of petrified wood. A more detailed analysis in 1999 revealed their true nature which resulted in a minor media frenzy, and formal publication of the find the following year.
Paleoecological analysis indicates that Sauroposeidon lived on the shores of the Gulf of Mexico, in a river delta. Extrapolations based on the more completely known Brachiosaurus indicate that the head of Sauroposeidon could reach 18 m (59 ft) in height with its neck extended, which would make it the tallest known dinosaur. With an estimated length of up to 34 m (112 ft) and a mass of 50–60 t (55–66 short tons), it also ranks among the longest and heaviest. However, this animal may not be as closely related to Brachiosaurus as previously thought, so these estimates may be inaccurate.
The first fossils classified as Sauroposeidon were four neck vertebrae discovered in rural Oklahoma, not far from the Texas border, in a claystone outcrop that dates the fossils to about 110 million years ago (mya). This falls within the Early Cretaceous Period, specifically between the Aptian and Albian epochs. These vertebrae were discovered in 1994 at the Antlers Formation in Atoka County, Oklahoma by Dr. Richard Cifelli and a team from the Oklahoma Museum of Natural History. Initially the fossils were believed to be simply too large to be the remains of an animal, and due to the state of preservation, believed to be tree trunks. In fact, they are the longest such bones known in dinosaurs. Thus, the vertebrae were stored until 1999, when Dr. Cifelli gave them to a graduate student, Matt Wedel, to analyze as part of a project. Upon their realization of the find"s significance, they issued a press release in October 1999, followed by official publication of their findings in the Journal of Vertebrate Paleontology in March 2000. The new species was named S. proteles, and the holotype is OMNH 53062.
The press release in 1999 immediately garnered international media attention, which led to many (inaccurate) news reports of "the largest dinosaur ever!". While it is true that Sauroposeidon is probably the tallest known dinosaur, it is neither the longest nor the most massive. Argentinosaurus is a better candidate for the title "World"s Largest Dinosaur" (presuming to ignore, as is conventional, Amphicoelias), though weak fossil evidence makes an exact ranking impossible.
The original Sauroposeidon find was composed of four articulated, mid-cervical vertebrae (numbers 5 to 8), with the cervical ribs in place. The vertebrae are extremely elongated, with the largest one having an overall length of 1.4 m (4.6 ft), making it the longest sauropod neck vertebra on record. Examination of the bones revealed that they are honeycombed with tiny air cells, and are very thin, like the bones of a chicken or an ostrich, making the neck lighter and easier to lift. The cervical ribs were remarkably long as well, with the longest measurable rib (on vertebra 6) measuring 3.42 m (11.2 ft) – about 18% longer than the longest rib reported for Giraffatitan, but exceeded in length by the cervical ribs of Mamenchisaurus.
Estimates of Sauroposeidon"s size are based on a comparison between the four Sauroposeidon vertebrae and the vertebrae of the HM SII specimen of Giraffatitan brancai, located in the Humboldt Museum in Berlin. The HM SII is the most complete brachiosaur known, though since it is composed of pieces from different individuals its proportions may not be totally accurate. Comparisons to the other relatives of Sauroposeidon are difficult due to limited remains.
The neck length of Sauroposeidon is estimated at 11.25–12 m (37–39 ft), compared to a neck length of 9 m (30 ft) for the HM SII Giraffatitan. This is based on the assumption that the rest of the neck has the same proportions as Giraffatitan, which is a reasonably good conjecture.
Sauroposeidon was probably able to raise its head 17–18 m (56–59 ft) above the ground, which is as high as a six-story building. In comparison, Giraffatitan could probably raise its head 13.5 m (44 ft) into the air.
Sauroposeidon"s shoulder height has been estimated at 6–7 m (20–23 ft) based on an interpretation of the animal as a brachiosaurid. Estimates of its total possible length have ranged from 28 m (92 ft) to 34 m (112 ft).
The mass of Sauroposeidon is estimated at 50–60 t (55–66 short tons). While the vertebrae of Sauroposeidon are 25–33% longer than Giraffatitan", they are only 10–15% larger in diameter. This means that while Sauroposeidon probably has a larger body than Giraffatitan its body is smaller in comparison to the size of its neck, so it did not weigh as much as a scaled-up Giraffatitan. By comparison, Giraffatitan might have weighed 36–40 t (40–44 short tons). This estimate of the Giraffatitan is an average of several different methodologies.
However, Sauroposeidon has a gracile neck compared to Giraffatitan. If the rest of the body turns out to be similarly slender, the mass estimate may be too high. This could be similar to the way the relatively robust Apatosaurus weighs far more than the longer but much slimmer Diplodocus. In addition, it is possible that sauropods may have had an air sac system, like those in birds, which could reduce all sauropod mass estimates by 20% or more.
Sauropods, which include the largest terrestrial animals of all time, were a very wide ranging and successful group. They first appeared in the Early Jurassic and soon spread across the world. By the time of the late Jurassic, North America and Africa were dominated by the diplodocids and brachiosaurids and, by the end of the Late Cretaceous, titanosaurids were widespread (though only in the southern hemisphere). Between these periods, in the Early Cretaceous, the fossil record is sparse. Few specimens have been found in North America from that time and those specimens that do exist are often fragmentary or represent juvenile members of their species. Most of the surviving sauropods at the time were also shrinking in size to a mere 15 m (49 ft) in length, and maybe 10–15 t (11–17 short tons), which makes the discovery of an extremely specialized super-giant like Sauroposeidon very unusual.
Sauroposeidon lived on the shores of the Gulf of Mexico, which ran through Oklahoma at that time, in a vast river delta similar to the Mississippi delta today. This paleoenvironment, which has been preserved in the Antlers Formation, also stretches from southwest Arkansas through southeastern Oklahoma and into northeastern Texas. This geological formation has not been dated radiometrically. Scientists have used biostratigraphic data and the fact that it shares several of the same genera as the Trinity Group of Texas, to surmise that this formation was laid down during the Albian stage of the Early Cretaceous Period, approximately 110 mya.The area preserved in this formation was a large floodplain that drained into a shallow inland sea. Several million years later, this sea would expand to the north, becoming the Western Interior Seaway and dividing North America in two for nearly the entire Late Cretaceous period. The paleoenvironment of Sauroposeidon consisted of tropical or sub-tropical forests, river deltas, coastal swamps, bayous and lagoons, probably similar to that of modern-day Louisiana.There were few predators which could attempt to attack a full-grown Sauroposeidon, but juveniles were likely to be preyed on by the contemporary Acrocanthosaurus atokensis  (a carnosaur slightly smaller than a Tyrannosaurus), which likely were the apex predators in this region,and the small coelurosaur Deinonychus antirrhopus. Sauroposeidon also shared its paleoenvironment with other dinosaurs, such as the sauropod Astrodon (Pleurocoelus) and the most common dinosaur in this region, the ornithopod Tenontosaurus. Other vertebrates present during this time included the amphibian Albanerpeton arthridion, the reptiles Atokasaurus metarsiodon and Ptilotodon wilsoni, the crurotarsan reptile Bernissartia, the cartilaginous fish Hybodus buderi and Lissodus anitae, the ray-finned fish Gyronchus dumblei, the crocodilian Goniopholis, and the turtles Glyptops and Naomichelys. Possible indeterminate bird remains are also known from the Antlers Formation. The fossil evidence suggests that the gar Lepisosteus was the most common vertebrate in this region. The early mammals known from this region included Atokatherium boreni and Paracimexomys crossi.

Brachiosaurus nougaredi

Brachiosaurus" nougaredi is a giant sauropod dinosaur from the family Brachiosauridae. It was originally assigned to the genus Brachiosaurus in 1960, though it almost certainly represents a different genus.
This species is known from fragmentary remains discovered in eastern Algeria, in the Sahara Desert. The present type material consists of a sacrum and some of the left metacarpals and phalanges. Found at the discovery site but not collected were partial bones of the left forearm, wrist bones, a right shin bone, and fragments that may have come from metatarsals. Albert-Fйlix de Lapparent, who described and named the material in 1960, reported the discovery locality as being in the Late Jurassic–age Taouratine Series (he assigned the rocks this age in part because of the presumed presence of Brachiosaurus), but more recent review assigns it to the "Continental intercalaire," which is considered to be of Albian age (late Early Cretaceous, significantly younger).
This material was found disjointed over an area of several hundred meters, and may not belong to one individual or even one species.Upchurch, Barrett and Dodson (2004) doubted its assignment to Brachiosaurus, and listed it as an unnamed brachiosaurid. The sacrum is of very large size, with a length of 130 centimetres (51 in) for four vertebrae compared to 95 centimetres (37 in) for five vertebrae in B. altithorax - the full "B." nougaredi sacrum with all five vertebrae could have been as long as 145 cm, a gigantic size even by brachiosaur standards,around 120 ft. long and 80+ tons Sauropod.The other bones attributed to this species are not of unusual size in comparison to B. altithorax or Giraffatitan brancai and may be from various species unrelated to the giant sacrum.

Fusuisaurus
The mysterious, never-before-restored, and downright colossal Fusuisaurus. The first and only true brachiosaur discovery known from China,this giant is unique in two critical ways: it is unusual in being so basal so late; and it is apparently more closely related to Brachiosaurus altithorax than any other species of brachiosaur. The ilium is extremely similar to Brachiosaurus, and the tail vertebrae follow a similar pattern. This species punches a hole in the notion that basal members of a clade can"t grow to gigantic sizes - sometimes they can even exceed the sizes of many derived members. The charcters of all recovered elements correspond well to a late survivor of a basal progenitor lineage for Brachiosaurus. This dinosaur is known for a very incomplete skeleton, including ilium and pubis claims, caudal vertebrae, ribs and dorsal part of the left femur. The remains, although fragmentary, are evidence of the existence of one of the largest sauropods of the Cretaceous, comparable in size to the American Sauroposeidon (about 101.3ft. (30 meters) long and 70+ tons)It is evidently not, as has sometimes been claimed, a basal titanosaur or a somphospondylian.
Often labeled in the Chinese press as the most basal titanosauriform known, the reputation is a bit premature. Evidently its distinctively brachiosaur features show that Fusuisaurus was considerably more advanced than the most basal titanosauriforms (Volkheimeria, "Lavocatitan" and the klamelisaurids). Pneumaticity is not very developed in the ribs, so this animal is likely more primitive than Brachiosaurus itself, despite being a far more recent species. It appears to be a living fossil that survived from the mid-Jurassic days of Brachiosaurus" direct ancestors, survivors of which seem to have long outlasted Brachiosaurus itself. How such instances of extremely long survival for such "holdover taxa" and basal bloodlines take place, particularly in a fast-evolving (and fast-turnover) warm-blooded class like Dinosauria, is still not properly understood.

Giraffatitan

Giraffatitan, meaning "giant giraffe", is a genus of sauropoddinosaur that lived during the late JurassicPeriod (Kimmeridgian-Tithonian stages). It was originally named as an African species of Brachiosaurus (B. brancai). Giraffatitan is one of the largest animals known to have walked the earth.
Giraffatitan was a sauropod, one of a group of four-legged, plant-eating dinosaurs with long necks and tails and relatively small brains. It had a giraffe-like build, with long forelimbs and a very long neck. The skull had a tall arch anterior to the eyes, consisting of the bony nares, a number of other openings, and "spatulate" teeth (resembling chisels). The first toe on its front foot and the first three toes on its hind feet were clawed.
Traditionally, the distinctive high-crested skull has been seen as a characteristic of the genus Brachiosaurus to which Giraffatitan brancai was originally referred, but because within the traditional Brachiosaurus material it is known only from Tanzanian specimens now assigned to Giraffatitan, it is possible that Brachiosaurus altithorax did not show this feature.
For many decades, Giraffatitan was claimed to be the largest dinosaur known, (ignoring the possibly larger but lost Amphicoelias) but in the later part of the 20th century several giant titanosaurians (Argentinosaurus, Puertasaurus and Futalognkosaurus) appear to have surpassed Giraffatitan in terms of sheer mass. However, Giraffatitan, along with Brachiosaurus are still the largest dinosaurs known from relatively complete material.
All size estimates for Giraffatitan are based on the specimen HMN SII,a subadult individual between 21.8–22.5 metres (72–74 ft) in length. Mass estimates are more problematic and historically have varied from as little as 15 tonnes (17 short tons) to as much as 78 tonnes (86 short tons).These extreme estimates are now considered unlikely due to flawed methodologies. More recent estimates based on models reconstructed from bone volume measurements, which take into account the extensive, weight-reducing air sac systems present in sauropods, and estimated muscle mass, are in the range of 23–37 tonnes (25–41 short tons).However, HMN SII is not the largest specimen known (an assertion supported by its subadult status) but HMN XV2, represented by a tibia 13% larger than the corresponding material on HMN SII,which might have attained 26 metres (85 ft) in length.
Giraffatitan brancai was first named and described by German paleontologist Werner Janensch in 1914 as Brachiosaurus brancai, based on several specimens recovered between 1909 and 1912 from the Tendaguru formation near Lindi, in what was then German East Africa, today Tanzania.
It is known from five partial skeletons, including three skulls and numerous fragmentary remains including skull material, some limb bones, vertebrae and teeth. It lived from 145 to 150 million years ago, during the Kimmeridgian to Tithonian ages of the Late Jurassic period.
A famous specimen of Giraffatitan brancai mounted in Museum fьr Naturkunde (Berlin) is one of the largest, and in fact the tallest, mounted skeletons in the world, as certified by the Guinness Book of Records. Beginning in 1909, Werner Janensch found many additional G. brancai specimens in Tanzania, Africa, including some nearly complete skeletons, and used them to create the composite mounted skeleton seen today.
Giraffatitan"s brain measured about 300 cmі, which, like those of other sauropods, was small compared to its massive body size. A 2009 study calculated its brain-to-body mass ratio (a rough estimate of possible intelligence) at a low 0.62 or 0.79, depending on the size estimate used. Giraffatitan is also similar to other sauropods in having an sacral enlargement above the hip which some older sources misleadingly referred to as a "second brain",but glycogen bodies are a more possible explanation.
The placement of Giraffatitan nostrils has been the source of much debate with Witmer (2001) describing in Science the hypothesized position of the fleshy nostrils in Giraffatitan in as many as five possible locations. Comparing the nares of dinosaurs with those of modern animals, he found that all species have their external nostril openings in the front, and that sauropods like Giraffatitan did not have nostrils on top of their heads, but near their snouts.
There has also been the hypothesis of various sauropods, such as Giraffatitan, possessing a trunk. The fact that there were no narrow-snouted sauropods (Giraffatitan included) tends to discredit such a hypothesis. Stronger evidence for the absence of a trunk is found in the teeth wear of Giraffatitan, which shows the kind of wear that would result from biting and tearing off of plant matter rather than purely grinding, which would be the result of having already ripped the leaves and branches off with its trunk.
If Giraffatitan was endothermic (warm-blooded), it would have taken an estimated ten years to reach full size, if it were instead poikilothermic (cold-blooded), then it would have required over 100 years to reach full size. As a warm-blooded animal, the daily energy demands of Giraffatitan would have been enormous; it would probably have needed to eat more than ~182 kg (400 lb) of food per day. If Giraffatitan was fully cold-blooded or was a passive bulk endotherm, it would have needed far less food to meet its daily energy needs. Some scientists have proposed that large dinosaurs like Giraffatitan were gigantotherms.
The nostrils of Giraffatitan, like the huge corresponding nasal openings in its skull, were long thought to be located on the top of the head. In past decades, scientists theorized that the animal used its nostrils like a snorkel, spending most of its time submerged in water in order to support its great mass. The current consensus view, however, is that Giraffatitan was a fully terrestrial animal. Studies have demonstrated that water pressure would have prevented the animal from breathing effectively while submerged and that its feet were too narrow for efficient aquatic use. Furthermore, new studies by Lawrence Witmer (2001) show that, while the nasal openings in the skull were placed high above the eyes, the nostrils would still have been close to the tip of the snout (a study which also lends support to the idea that the tall "crests" of brachiosaurs supported some sort of fleshy resonating chamber).

Lusotitan

Lusotitan is a genus of herbivorous brachiosaurid sauropod dinosaur from the Late Jurassic Period of Portugal.
In 1947 Manuel de Matos, a member of the Geological Survey of Portugal, discovered large sauropod fossils in the Portuguese Lourinhг Formation that date back to the Tithonian stage of the Late Jurassic period. The finds consisted of a partial skeleton lacking the skull and individual vertebrae uncovered in several locations. These remains include 28 vertebrae and elements of the appendicular skeleton.
It has been estimated that Lusotitan was 25 meters (82 feet) long. It had long forearms, one of the reasons Mateus assigned it to the Brachiosauridae.
The Lourinhг Formation of western Portugal was likely to be formed during the Kimmeridgian or Tithonian ages of the Late Jurassic period. The area is a coastal region with a strong marine influence. Its flora and fauna are similar to the Morrison Formation in the United States, and the Tendaguru Formation in Tanzania.Lusotitan is the largest dinosaur that has been discovered in the area. Lusotitan lived alongside species of the predatory theropods Allosaurus (A. europaeus), Ceratosaurus, Lourinhanosaurus, and Torvosaurus,