Lourinhasaurus alenquerensis is a large sauropod known from a substantial, disarticulated partial skeleton found near Alenquer in western Portugal. First described as a species of Apatosaurus, it later received its own genus and was re-examined with modern anatomical and phylogenetic methods. The revised specimen supports a distinct Late Jurassic animal, usually placed among macronarian sauropods, although its precise relationships have varied between analyses.
Quick facts
| Species | Lourinhasaurus alenquerensis (Lapparent & Zbyszewski, 1957) |
|---|---|
| Age | Late Jurassic, upper Kimmeridgian to lower Tithonian |
| Formation | Sobral Formation, Alenquer, Portugal |
| Group | Macronaria; recovered among camarasauromorphs |
| Type specimen | Moinho do Carmo lectotype, Museu Geológico collection |
| Estimated size | Large sauropod; full-body estimates depend on missing bones |
From an Apatosaurus species to Lourinhasaurus
The bones were collected at Moinho do Carmo, near Alenquer, in the middle of the twentieth century. In 1957, Albert-Félix de Lapparent and Georges Zbyszewski named them Apatosaurus alenquerensis. The material was subsequently compared with Camarasaurus, reflecting the limited descriptions and incomplete comparative framework then available. In 1998, Dantas and colleagues established the genus Lourinhasaurus for the Portuguese species. Antunes and Mateus later fixed the Moinho do Carmo specimen as its lectotype, anchoring the name to a defined fossil collection.
The lectotype is held in the Museu Geológico in Lisbon. It preserves elements of the vertebral column, ribs, shoulder and pelvic girdles, and limbs. These bones make it one of the more informative upper Jurassic sauropod specimens from Europe, but they were not recovered as a fully articulated skeleton. The skull and much of the neck are missing, so the animal's head shape and complete proportions cannot be read directly from the type.
A Late Jurassic Portuguese landscape
The Moinho do Carmo material comes from the Sobral Formation. Its relevant beds are generally assigned to the upper Kimmeridgian or lower Tithonian, near the end of the Jurassic. That age range reflects the correlation of sedimentary units; it is not a precise date for the animal's death. The wider region records continental environments with rivers and floodplains, alongside changing coastal and marine influence.
Other dinosaurs are known from the broader Late Jurassic deposits of Portugal, including large predators and herbivores. Their presence in the same regional rock record does not show that they all met at one place or time. Formation-level faunas combine fossils accumulated over intervals that can be long and environmentally varied.
What the anatomy can diagnose
A detailed 2014 reassessment described previously overlooked parts of the Moinho do Carmo collection and updated the anatomical characters used in evolutionary analyses. Features of the sacral and tail vertebrae, the ischium and the femur help distinguish the specimen from other sauropods. The femur has a marked deflection of its shaft, while parts of the vertebral series show distinctive ridges and depressions. These characters support a diagnosable taxon rather than a name based only on general resemblance.
The same study recovered Lourinhasaurus as a macronarian within Camarasauromorpha and, in some analyses, close to Camarasaurus. Such a result describes a branching relationship inferred from shared anatomy. It does not mean that the Portuguese animal was a species of Camarasaurus, nor that one genus directly descended from the other. Different character matrices and taxon samples can alter the exact branching order.
Size, diet and reconstruction
The preserved skeleton identifies a large-bodied, long-necked sauropod. As a sauropod, it was herbivorous, but its exact plant preferences are not preserved. A complete body outline has to be reconstructed by comparison because the specimen lacks the skull, much of the neck and other portions needed to set every proportion. Estimates of total length therefore depend on which related animal supplies the missing measurements.
The fossils establish that a distinct macronarian sauropod lived in Late Jurassic Portugal. They do not prove that its ecology matched that of every other European giant in the same formation. The dinosaur catalogue places Lourinhasaurus alongside other profiles such as Camarasaurus to make anatomical comparisons easier while keeping the Portuguese specimen's own evidence in view.
Frequently asked questions
What is the Lourinhasaurus type specimen?
The lectotype is the partial skeleton from Moinho do Carmo near Alenquer, held in Lisbon's Museu Geológico. It preserves parts of the spine, ribs, girdles and limbs, but not a complete skeleton.
Why was Lourinhasaurus once called Apatosaurus?
The Portuguese bones were named Apatosaurus alenquerensis in 1957. Later anatomical study showed that the material warranted its own genus, Lourinhasaurus, established in 1998.
Where and when did it live?
It comes from the Sobral Formation near Alenquer, Portugal, in strata generally assigned to the upper Kimmeridgian or lower Tithonian of the Late Jurassic.
How certain is its relationship to Camarasaurus?
A 2014 reassessment supported Lourinhasaurus as a distinct macronarian and recovered it near Camarasaurus in some analyses. That is a tree-based relationship, not proof that the genera were identical or directly ancestral.