Losillasaurus, CASANOVAS ET AL., 2001

Royo-Torres, Rafael, Cobos, Alberto, Mocho, Pedro & Alcalá, Luis, 2021, Origin and evolution of turiasaur dinosaurs set by means of a new ‘ rosetta’ specimen from Spain, Zoological Journal of the Linnean Society 191, pp. 201-227 : 219-220

LOSILLASAURUS CASANOVAS ET AL., 2001

Figures: See Casanovas et al., 2001: figs 1–7; Figs 1–16; Supporting Information, File S3.

Type species: Losillasaurus giganteus Casanovas et al. (2001) .

Holotype: Anterior caudal vertebra housed in the Museo de Ciencias Naturales de Valencia ( MCNV).

Paratype: Two anterior caudal vertebrae housed in the Museo de Ciencias Naturales de Valencia ( MCNV) .

Type locality and horizon: La Cañada site (Valencia), V i l l a r d e l A r z o b i s p o Fo r m a t i o n (C a s a n o v a s et al., 2001; Royo-Torres et al., 2006). Dated as Kimmeridgian according to the data of Campos-Soto et al. (2019).

Referred material: The material referred to Losillasaurus comes from the same specimen from where the holotype and paratype were selected. It consists of a skull fragment and partial postcranial skeleton (see Supporting Information, File S1). A second specimen, described in this paper, is from the San Lorenzo site (Riodeva, Teruel, Spain) in the Villar del Arzobispo Formation. It consists of a partial skull with teeth and partial postcranial skeleton (see the previous description section and Supporting Information, File S1). A third specimen referred to as Losillasaurus is a complete anterior caudal vertebra ( SHN 180) found in Baleal (Peniche municipality, Portugal) in the Praia de Amoreira-Porto Novo Formation, dated as Upper Kimmeridgian–Lower Tithonian ( Manuppella et al., 1999; Mocho et al., 2017b).

Revised diagnosis: Losillasaurus is diagnosed by eight autapomorphies: (1) (new) lateral surface of the premaxilla and maxilla with dorsoventrally elongated grooves convergent with diplodocids and Nemegtosaurus ( Mannion et al., 2019) ; (2) (new) a maxillary tooth with a secondary apex on the distal edge; (3) markedly curved neural spines of the proximal caudal vertebrae that in the first and second caudal vertebrae produce a pronounced cutlass-like shape in the lateral view ( Casanovas et al., 2001; Upchurch et al., 2004a); (4) (new) presence of a dorsoventral ridge in the anterolateral surface of the spine at least between the fourth and tenthcaudal vertebrae (it is not clearly present in the first three caudal vertebrae and disappears in the 11 th caudal vertebra); (5) (new) caudal neural spines with a shallow dorsal groove with directed anteroposteriorly, bigger in the anteriormost caudal vertebrae, especially in the first and second bones and shallow from the third to the 30 th caudal vertebrae; (6) (new) the long-axis of the obturator foramen is perpendicular to the long-axis of the pubis; (7) (new) the lateral trochanter of the fibula is concave and rugose; and (8) (new) the tibial condyle of the femur is twice as large as the fibula condyle.

Additional comments: The character, anteroposterior length at the base of the neural spines of the proximal caudal vertebrae being approximately half the height of the spine (ratio = 0.5), was included in the original diagnosis ( Casanovas et al., 2001) and accepted in Upchurch et al. (2004a). However, this is not considered valid as the spines are compressed by taphonomic deformation.