#ootaxon

[mesozoicmarket]

A fossilized dinosaur egg from an Elongatoolithus sp., likely an oviraptorid from the Nanxiong Formation, Ganzhou, Jiangxi Province, China. These types of eggs are often associated with oviraptorosaurs with some eggs containing embryos as well as adult animals buried with their nests. Fossilized theropod and other dinosaur eggs from China used to be commonly available in the past at fossil shows until additional restrictions or bans were placed on eggs. There are a large number of oviraptorid genera found in the Nanxiong Formation during the end Maastrichtian such as Banji, Corythoraptor, Ganzhousaurus, Huanansaurus, Jiangxisaurus, Nankangia, Shixinggia, Tongtianlong, and likely more to come. This makes it difficult, if not impossible to say which specific taxa it belongs to. The egg is roughly about give or take, 14cm long, 6.6cm wide, and 4.2cm thick. The thickness of the eggshells are about 0.7mm. Given how damaged the specimen is, the measurements are likely not perfect; however, it likely belongs to one of the smaller species.

[mesozoicmarket]

A pair fossilized bird eggshell of a Gastornis sp. or the oospecies, Ornitholithus arcuatus from Bouches du Rhône, France. These Lower Eocene aged eggshells have a thickness of around 2 mm implying they were laid by giant birds like Gastornis which distinguishes it from smaller contemporary bird ootaxa like Ornitholithus biroi which has a 1mm thickness. The right specimen comes from Saint-Léger while the left comes from Saint-Antonin-sur-Bayon.

[mesozoicmarket]

A fossilized bird eggshell from an elephant bird or Aepyornis sp. from Itampolo, Madagascar. While eggs of these massive paleognath birds were seen in the past at high end auctions, much of what still remains on the market are isolated eggshells which are often used to make composite eggs. This species of flightless ratite bird was hunted to extinction by humans relatively recently around 1000 years ago. Unfortunately, there are no surviving members of the elephant bird clade with their closest living relatives being kiwis.

[mesozoicmarket]

A partial dinosaur tooth of an indeterminate theropod, possibly an early abelisaurid or allosaurid from the Isalo III Formation in Ambondromamy, Madagascar. The tooth has a serration density of around 16/5 mm on both carinae which rules out a misidentified Cretaceous aged Majungasaurus crenatissimus. The morphology has some resemblance to that of premaxillary teeth known from abelisaurids and Allosaurus.

[mesozoicmarket]

A fossilized cluster of dinosaur eggshells or the oospecies Preprismatoolithus coloradensis from the Morrison Formation in Delta County, Colorado, United States. This type of eggshell was originally hypothesized to belong to hypsilophodontid ornithischians but now assume to belong to some kind of theropod. Some of the theropod genera present in this deposit that could match the size of these eggshells are Allosaurus, Ceratosaurus, Torvosaurus, and Marshosaurus.

[mesozoicmarket]

A fossilized cluster of dinosaur eggshells of an indeterminate titanosaurian sauropod from the Allen Formation near General Roca, Rio Negro, Argentina. While often attributed to Saltasaurus robustus, the genus no longer occurs in this deposit. Many titanosaurs like Bonatitan and Rocasaurus have since been described from the region and it is likely impossible to determine which taxa an egg or eggshell would belong to. This type of eggshell is often referred to the ootaxa Megaloolithus sp. which is often attributed to titanosaurian sauropods. Eggshells labeled as Saltasaurus were once very common in the fossil trade, but has since become increasingly scarce since Argentina's ban on fossils a few decades back.