Losillasaurus

Losillasaurus Temporal range: Late Jurassic, 157.3–145 Ma PreꞒ Ꞓ O S D C P T J K Pg N
L. giganteus vertebra
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	Saurischia
Clade:	†Sauropodomorpha
Clade:	†Sauropoda
Clade:	†Turiasauria
Genus:	†Losillasaurus Casanovas et al., 2001
Species:	†L. giganteus
Binomial name
†Losillasaurus giganteus Casanovas et al., 2001

Losillasaurus (meaning "Losilla lizard") is a genus of sauropod dinosaur from the Late Jurassic and possibly Early Cretaceous (Kimmeridgian-?Berriasian) in the southeast of Spain. The type species of the turiasaurian Losillasaurus giganteus was discovered in the Villar del Arzobispo Formation in Valencia and formally described by Casanovas, Santafé and Sanz in 2001. The holotype material is from a subadult and includes part of a skull; complete cervical, dorsal, sacral, and caudal vertebrae as well as several fragments; skeletal elements from the limbs including a humerus, ulna, radius, and metacarpal; sternal plates; and from the pelvis: the ilium, ischium, and pubis. The genus is characterized by the dimension and shape of the neural spine of the proximal caudal vertebrae.^[1][2] The humerus is 143 centimetres (56 in) long,^[3] which despite being from a subadult specimen is within 20% of the size of Paralititan.^[4] The size estimation proposed by Francisco Gascó in his master thesis is 15–18 m (49–59 ft) and 12-15 tons.^[5]

Description

Reconstruction of Losillasaurus giganteus

Several specimens of L. giganteus were described in 2019 and 2020 - one such specimen (SHN 180) consists of a single anterior caudal vertebra, while another (the holotype) consists of a partial skull with teeth and partial postcranial skeleton.^[6] According to Rafael Royo-Torres et al., the specimen helps scientists to understand tooth variation, allows the positioning of isolated heart-shaped teeth in the skull and demonstrates heterodonty in Turiasauria.^[7]

References

1. Casanovas, Maria Lourdes; Santafé, José Vicente; Sanz, José Luis (2001). "Losillasaurus giganteus, un nuevo saurópodo del tránsito Jurásico-Cretácico e la Cuenca de "Los Serranos" (Valencia, España)". Paleontologia i Evolució (in Spanish). 32–33: 99–122.
2. Ruiz-Omeñaca, Jose Ignacio (2001). "Losillasaurus giganteus, a new Spanish sauropod". Dinosaur Mailing List.
3. Ruiz-Omeñaca, Jose Ignacio (2001)."Re: Losillasaurus giganteus, a new Spanish sauropod". Dinosaur Mailing List.
4. Taylor, Mike (2001). "Re: Losillasaurus giganteus, a new Spanish sauropod". Dinosaur Mailing List
5. Gascó, F (2009): Sistemática y anatomía funcional de Losillasaurus giganteus Casanovas, Santafé & Sanz, 2001 (Turiasauria, Sauropoda). Universidad Autónoma de Madrid.
6. Campos-Soto S, Benito MI, Cobos A, Caus E, Quijada IE, Suarez-Gonzalez P, Mas R, Royo-Torres R, Alcalá L. 2019. Revisiting the age and palaeoenvironments of the Upper Jurassic–Lower Cretaceous? Dinosaur-bearing sedimentary record of eastern Spain: implications for Iberian palaeogeography. Journal of Iberian Geology 45: 471–510.
7. Rafael Royo-Torres; Alberto Cobos; Pedro Mocho; Luis Alcalá (2020). "Origin and evolution of turiasaur dinosaurs set by means of a new 'rosetta' specimen from Spain". Zoological Journal of the Linnean Society. 191: 201–227. doi:10.1093/zoolinnean/zlaa091.