Discover the remarkably preserved skin of Monsecosuchus depereti, an extinct crocodilian about the size of a domestic cat that inhabited the tropical wetlands of early Cretaceous Spain. Paleontologists have meticulously reconstructed its scales, sensory organs, and even potential stripes along its tail.
Holotype specimen of Monsecosuchus depereti. Image credit: Castillo-Visa et al., doi: 10.1093/zoolinnean/zlag076.
The fossilized skeleton of Monsecosuchus depereti was excavated in 1902 by geologist Luis María Vidal from a quarry in Catalonia, Spain. This 50 cm long specimen has been part of the Barcelona Museum of Natural Sciences collection for over a century.
“Crocodilians, including Monsecosuchus depereti and their extinct relatives, possess a vast fossil record dating back to the Late Triassic period,” stated Dr. Oscar Castillo-Viza from the Miquel Crusafont Catalan Institute of Paleontology at the Autonomous University of Barcelona.
“However, preserved soft tissues like skin and cartilage are exceedingly rare, with exceptions primarily in marine thalamozoans.”
Paleontologists utilized ultraviolet (UV) light to identify and describe cartilaginous and epidermal tissues, making Monsecosuchus depereti one of the most complete and oldest preserved skin specimens of crocodilians.
“Ultraviolet light reveals intricate details hidden within the rock,” Dr. Castillo-Viza elaborated.
Holotype specimen of Monsecosuchus depereti under UV light. Image credit: Castillo-Visa et al., doi: 10.1093/zoolinnean/zlag076.
Researchers discovered that the epidermal scales of Monsecosuchus depereti formed discrete patches across the arms, thorax, legs, and tail, with the best-preserved skin located on the forelimbs and thorax.
They also identified potential integumentary sensory organs—specialized scales on the body’s periphery—indicating that such structures may have initially evolved modestly before becoming widespread across later crocodilian species.
These small sensory organs, abundant in modern crocodiles’ faces and bodies, are sensitive to pressure and vibrations, aiding in prey detection in murky waters. Their evolutionary beginnings appear less complex than previously assumed.
“In contemporary crocodiles, these organs are crucial for sensing changes in touch and water pressure, and they may also react to thermal and chemical stimuli,” noted the scientists.
Preservation of cartilage tissue in the thoracic region suggests that Monsecosuchus depereti possessed adaptations for enhanced respiratory efficiency.
These bony or cartilaginous projections, seen in modern birds, serve to strengthen the thorax and improve breathing mechanics, suggesting that ancient crocodiles were more active and aerobically capable than the stereotypical image of modern crocodiles.
“These characteristics indicate that, despite being an ancient species, it was well-adapted for a semi-aquatic lifestyle,” Dr. Castillo-Viza stated.
Monsecosuchus depereti lacked two common features of modern crocodiles: deep caudal “fins” and sharply pointed limb scales, implying a sleeker silhouette compared to today’s Nile crocodile.
The research team also uncovered evidence of visually striking color patterns, including stripes along the tail.
This alternating dark and light banding is observed in modern crocodiles and other reptiles for camouflage and species recognition, serving as a vivid reminder of how conservative evolution can be.
While the precise color of the crocodile’s tail remains uncertain, expectations lean towards similarities with modern species, which also exhibit varied color patterns,” explained Dr. Albert Serres from the Miquel Crusafont Catalan Institute of Paleontology and Conca della Museum.
The research team’s findings were published in the Zoological Journal of the Linnean Society.
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Oscar Castillo – Visa et al.. 2026. Soft tissue preservation in Barremian Monsecosuchus depereti (Neoschiinae: Atoposauridae). Zoological Journal of the Linnean Society 207 (2): zlag076; doi: 10.1093/zoolinnean/zlag076
Source: www.sci.news