Iberospinus
Iberospinus or (meaning "Iberian spine") is an extinct genus of spinosaurid dinosaur from the Early Cretaceous (Barremian) Papo Seco Formation of Portugal. The genus contains a single species, I. natarioi, known from several assorted bones belonging to one individual. "Iberospinus" represents one of four known spinosaurid taxa from the Iberian Peninsula, the others being "Baryonyx," "Vallibonavenatrix", and "Camarillasaurus". It is important for its implications of the geographical origin of Spinosauridae and the suggested presence of an at least semi-aquatic lifestyle early in the evolution of this clade. Discovery and naming. The first fossil material was discovered in 1999 , with additional expeditions from 2004 to 2008. After being described as a specimen of "Baryonyx" in 2011, it was realised to have been a unique species in 2019. Additional material was discovered in a June 2020 expedition, after which "Iberospinus" was described as a new genus and species in 2022 by Octávio Mateus and Darío Estraviz-López. "Iberospinus" is currently known from dentary fragments, teeth, an incomplete right scapula, partial dorsal and caudal vertebrae, rib fragments"," a partial pubis, two incomplete calcanea, and a pedal ungual phalanx"." All of the material belongs to one individual. The holotype material represents one  of the most complete spinosaurid specimens in the world. Of the generic name, ""Iberospinus"," "ibero," is derived from "Iberia", a Roman name for the Iberian Peninsula, while the Latin "spinus," or means spine, after the elongated neural spines of related spinosaurids. The specific name, ""natarioi", " honors Carlos Natário, the discoverer of the holotype. Description. The dentary (lower jaw) of "Iberospinus" shows an intricate neurovascular system that would connect the teeth and the external foramina. A series of replacement teeth are also preserved in the dentary. Characteristics of the bones, especially in the tail and pedal ungual phalanx, indicate a possible  semi-aquatic lifestyle, though the extreme features in some related spinosaurines are not seen. The following autapomorphies distinguish "Iberospinus". The dentary bone contains a single foramen within the Meckelian sulcus and has a straight ventral edge instead of curved as in most other spinosaurids. Laminae are present in the pleurocoelic depression of the mediodistal tail vertebrae. The shoulder blade has a straight anterior rim without a protruding acromion and a coracoidal contact occupying the entire ventral surface. The pubic apron is thick throughout the entire length of the pubic shaft. There is a mound-like eminence in the proximal lateral  portion of the pubic bone. Classification. "Iberospinus" was recovered within the Spinosauridae, outside of both the Baryonychinae and the Spinosaurinae. However, Mateus & Estraviz-López (2022) explain that the fossil material shows some characteristics of baryonichines, suggesting a closer relation to the group. An adjusted cladogram after the describing authors is shown below: