Dicraeosauridae

Amargasaurus (; "La Amarga lizard") is a genus of sauropod dinosaur from the Early Cretaceous epoch (129.4–122.46 mya) of what is now Argentina. The only known skeleton was discovered in 1984 and is virtually complete, including a fragmentary skull, making Amargasaurus one of the best-known sauropods of its epoch. Amargasaurus was first described in 1991 and contains a single known species, Amargasaurus cazaui. It was a large animal, but small for a sauropod, reaching in length. Most distinctively, it sported two parallel rows of tall spines down its neck and back, taller than in any other kno

Dicraeosaurus (Gr. , ' "bifurcated, double-headed" + Gr. , ' "lizard") is a genus of diplodocoid sauropod dinosaur that lived in what is now Lindi Region, Tanzania during the late Jurassic period. The genus was named for the neural spines on the back of its neck. The first fossil was described by paleontologist Werner Janensch in 1914.

Brachytrachelopan is a genus of short-necked sauropod dinosaur from the Late Jurassic (Oxfordian to Tithonian) of Argentina. The holotype and only known specimen (Museo Paleontológico Egidio Feruglio MPEF-PV 1716) was collected from an erosional exposure of fluvial sandstone within the Cañadón Calcáreo Formation on a hill approximately north-northeast of Cerro Cóndor, Chubut Province, in west-central Argentina, South America. Though very incomplete, the skeletal elements recovered were found in articulation and include eight cervical, twelve dorsal, and three sacral vertebrae, as well as proxi

Bajadasaurus is a genus of sauropod dinosaur from the Early Cretaceous epoch (late Berriasian to Valanginian stages, between 145 and 132.9 million years ago) of northern Patagonia, Argentina. It was first described in 2019 based on a single specimen found in 2010 that includes a largely complete skull and parts of the neck. The only species is Bajadasaurus pronuspinax. The genus is classified as a member of the Dicraeosauridae, a group of relatively small and short-necked sauropods.

Dicraeosauridae is a family of diplodocoid sauropods who are the sister group to Diplodocidae. Dicraeosaurids are a part of the Flagellicaudata, along with Diplodocidae. Dicraeosauridae includes genera such as Amargasaurus, Suuwassea, Dicraeosaurus, and Brachytrachelopan. Definitive genera of this family have been found in North America, Africa, and South America. The Asian taxa Lingwulong and Tharosaurus have been suggested to be dicraeosaurids, but some authors disagree with this classification. Their temporal range is from the Early or Middle Jurassic to the Early Cretaceous. Few dicraeosau

Amargatitanis (meaning "Amarga giant") is a genus of dicraeosaurid sauropod dinosaur (a type of large, long-necked quadrupedal herbivorous dinosaur) from the Barremian-aged (Lower Cretaceous) La Amarga Formation of Neuquén, Argentina. It is known from a single, incomplete postcranial skeleton consisting of a partial hindlimb, ischium, and two vertebrae. These remains were unearthed by Argentine paleontologist José Bonaparte in 1983 during an expedition by the Museo Argentino de Ciencias Naturales and later described as a new genus and species, Amargatitanis macni by Sebastián Apesteguía. The g

Lingwulong is a genus of diplodocoid sauropod dinosaur from the Middle Jurassic of what is now Lingwu, Yinchuan, Ningxia, China. The type and only species is L. shenqi, known from several partial skeletons. It is one of the earliest neosauropods ever discovered, as well as the only definitive diplodocoid from east Asia.

Dyslocosaurus (meaning "hard-to-place lizard") a genus of sauropod dinosaur from the Late Jurassic Period of Wyoming, North America. The holotype or type specimen the genus is based on, AC 663, is part of the collection of the Amherst College Museum of Natural History. It was collected by professor Frederic Brewster Loomis. However, the only available information regarding its provenance is that given on the label: "Lance Creek", a county in east Wyoming. Loomis himself thought that it stemmed from the Lance Formation, dating from the Late Cretaceous (Maastrichtian).

Suuwassea is a genus of dicraeosaurid sauropod dinosaur found in Upper Jurassic strata of the Morrison Formation, located in southern Carbon County, Montana, United States. The fossil remains were recovered in a series of expeditions during a period spanning the years 1999 and 2000 and were described by J.D. Harris and Peter Dodson in 2004. They consist of a disarticulated but associated partial skeleton, including partial vertebral series and limb bones.

Tharosaurus (meaning "Thar Desert lizard") is an extinct genus of potentially dubious eusauropod sauropod dinosaurs from the Middle Jurassic Jaisalmer Formation of India. The genus contains a single species, Tharosaurus indicus, known from a fragmentary skeleton including several vertebrae and a rib. When it was named in 2023, Tharosaurus was interpreted as the earliest known diplodocoid and the first member of this clade described from India. However, a later revision of the fossil material argued for a position outside of this clade, as an indeterminate eusauropod. This revision could not fi

Athenar is an extinct genus of dicraeosaurid sauropod dinosaur from the Late Jurassic of Utah, United States. The genus contains a single species, Athenar bermani, which was described by John Whitlock and colleagues in 2025 based on the holotype specimen CM 26552: a and previously ascribed to the genus Diplodocus. The specimen was found in rocks belonging to the Morrison Formation at the Carnegie Quarry at Dinosaur National Monument.

Pilmatueia is a genus of diplodocoid sauropods belonging to the family Dicraeosauridae that lived during the Early Cretaceous in what is now Argentina. Its type and only species is Pilmatueia faundezi. Pilmatueia was probably closely related to other South American dicraeosaurids such as Amargasaurus. Like other dicraeosaurids, Pilmatueia was relatively small for a sauropod. The vertebrae of Pilmatueia were more extensively hollowed out by air sacs than in other dicraeosaurids, which otherwise were characterized by a reduction in the air sac system compared to other sauropods. Pilmatueia dates

Smitanosaurus (meaning "smith lizard") is a genus of dicraeosaurid sauropod dinosaur from the Late Jurassic of Colorado. The genus contains one species, S. agilis, originally assigned to the defunct genus Morosaurus.