Dinosaur bonebed amber from an original swamp forest soil.

Area of Science:

• Paleontology
• Paleoecology
• Geology

Background:

• Dinosaur bonebeds with amber are rare but valuable for understanding ancient ecosystems.
• Previous discoveries were limited by preservation and taphonomic biases.
• The Ariño site in Spain offers a unique opportunity to study associated bonebeds and amber.

Purpose of the Study:

• To describe and analyze the fossiliferous amber from the Lower Cretaceous dinosaur bonebed at Ariño, Spain.
• To investigate the palaeodiversity and taphonomic characteristics of this exceptional locality.
• To reconstruct the paleoecology of the Ariño site using complementary data from bonebed and amber preservation.

Main Methods:

• Multidisciplinary approach combining paleontological and geological analyses.
• Detailed description of amber and its bioinclusions (insects, arachnids, plants, vertebrates, feather).
• Analysis of associated microfossil data (charophytes, palynomorphs, ostracods).

Main Results:

• Amber found in both in situ root layer and a litter layer rich in aerial pieces.
• Amber contains diverse bioinclusions: 11 insect orders, arachnids, plant, and vertebrate remains, including a feather.
• Ariño represents the most prolific and diverse locality with associated dinosaur bonebed and fossiliferous amber, showing minimal pre-burial transport.

Conclusions:

• The Ariño site provides unprecedentedly complete and reliable paleoecological data due to exceptional preservation.
• The association of dinosaur bonebed and fossiliferous amber offers complementary insights into terrestrial ecosystems.
• This discovery enhances our understanding of Lower Cretaceous ecosystems and the taphonomy of fossiliferous amber.