The Kristianstad Basin is a Cretaceous-age structural basin and geological formation in northeastern Skåne, the southernmost province of Sweden. The sediments in the basin preserves a wide assortment of taxa represented in its fossil record, including the only non-avian dinosaur fossils in Sweden and one of the world's most diverse mosasaur faunas. Though a majority of the taxa listed below lived during the latest early Campanian (c. 80.5 million years ago; fossils from the site Ivö Klack alone from this time compromise about 40 vertebrate species and more than 200 invertebrate species), the Kristianstad Basin preserves fossils ranging in age from the early Santonian (c. 86.3 million years ago) to the early Maastrichtian (c. 72.1 million years ago); some of the animals in the list were not contemporaries, but separated from each other in time by several million years. The time spans from which fossils have been recovered is included for each species in the list.
Bony fish
Ray-finned fish
Cartilaginous fish
Sharks
Holocephali
Rays
Crocodylomorphs In addition to the remains referred to Aigialosuchus, detached and unidentified crocodylomorph scutes have also been discovered in Campanian-age deposits at Ivö Klack.
Dinosaurs
Non-avian dinosaurs
Birds In addition to the fossils described below, indeterminate hesperornithiform remains have also been recovered from Åsen.
Mosasaurs
Plesiosaurs The last comprehensive review of the plesiosaur fauna in the Kristianstad Basin was done by paleontologist Per-Ove Persson in the 1960s and his taxonomy is still used with caution, pending a much-needed new review.
Pterosaurs Possible pterosaur bone fragments have been recovered from earliest Campanian-age deposits at Ullstorp, though they remain unpublished.
Scincomorpha Fossils of terrestrial scincomorph lizards have been recovered in the Kristianstad Basin, but are as of yet unpublished.
Turtles In addition to the fossils described below, indeterminate turtle remains, including limb bones and carapace fragments, have also been recovered from Ivö Klack, Ugnsmunnarna, Ignaberga and Åsen.
Invertebrates Note: Although the Kristianstad Basin is incredibly rich in invertebrate fossils and diversity, with hundreds of species, the creation of a full list is impossible due to a lack of published overviews and recent examinations. Which lists are incomplete is specified below and estimates in regards to how many species are actually present are included if possible.
Bivalves The bivalves are the most species-rich group present in the Kristianstad Basin, with Surlyk & Sørenson (2010) stating that close to 70 distinct species were present at Ivö Klack alone.
Brachiopods According to Surlyk & Sørenson (2010) there were 27 distinct species of brachiopods present at Ivö Klack alone.
Bryozoans Fossils of bryozoans are common in several sites throughout the Kristianstad Basin.
Cephalopods
Belemnites
Ammonites According to Surlyk & Sørenson, a large species of ammonite is also known from Ivö Klack.
Chitons
Corals Fossils of corals are common in several sites throughout the Kristianstad Basin. The list below only accounts for the recently revised diversity of corals found at Ivö Klack.
Crinoids Fossils of crinoids have been found at several sites throughout the Kristianstad Basin.
Crustaceans
Echinoids According to Surlyk & Sørenson (2010) there were 18 distinct species of echinoids present at Ivö Klack alone.
Gastropods According to Surlyk & Sørenson (2010), 19 species of gastropods could be identified from fossils just from the latest Early Campanian of Ivö Klack. Their subsequent 2011 study on the gastropods of the site only listed the 15 species accounted for below.
Polychaetes In addition to the diverse polychaete worm fauna of Ivö Klack listed below, encrusters of serpulid polychaetes have also been discovered at Åsen, though they are considerably fewer in number there and as of yet unpublished.
Sponges Fossil sponges have been recovered at fossil sites in the Kristianstad Basin.
Starfish Fossils of starfish have been found at several sites in the Kristianstad Basin. According to Surlyk & Sørenson (2010) there were 16 distinct species of starfish present at Ivö Klack alone.
Flora
The Campanian flora of the Kristianstad Basin thrived in a warm, humid, temperate to subtropical environment, likely a lush, forested floodplain or coastal wetland adjacent to a shallow marine embayment. The presence of abundant dinoflagellates and marine invertebrates in the palynological and fossil assemblages suggests that plant remains were transported from nearby terrestrial habitats into a nearshore marine setting. The dominance of thermophilic angiosperms like Debeyea haldemiana, alongside cycadophytes and conifers, points to a climate with high temperatures and significant rainfall, supporting dense vegetation, while absence of mangrove-specific taxa and the presence of floodplain-associated genera indicate that the flora originated from inland forests or wetlands rather than intertidal mangroves. Lycophyta Megaspores from the Åsen locality include Triletes, Verrutriletes, Baculitriletes, Echitriletes, and Richnospora. The paleoenvironment suggests a terrestrial to marginal aquatic setting, likely a wetland or floodplain with periodic inundation, supporting lush vegetation, as indicated by megaspores, fossil flowers, and Normapolles pollen grains. Modern analogues are freshwater marshes, swamps, or lake margins where Isoetes grow in shallow, nutrient-rich waters with emergent or submerged vegetation. Local flowers have been found preserved as excepcional 3D fossils, atributted to their charcoal composition. These fossils where probably washed out into litter acummulations after local forest fires. No strong evidence supports mangroves in the Campanian at Åsen. Fossil stems with mangrove-like habits lack modern mangrove adaptations and were likely freshwater or marginally marine.
Gymnosperms
Angiosperms
See also List of fossil sites (with link directory) List of dinosaur-bearing rock formations Paleobiota of the Niobrara Formation
References
Citations
General bibliography
Web sources
