Middle Triassic age, Guanling Formation, Xingyi, Guizhou, China.
- Indigenous to China, K. hui is commonly discovered within the Triassic deposits of Guizhou Province, China.
- These small reptiles, only found in China, once flourished in large populations - thousands swimming in the shallow waters of an intercontinental sea - the species was discovered in 1958.
- Their large numbers are indicative that K. hui was a prey species, being a valuable food resource for larger predators.
- Preserved in a matrix of compacted fine volcanic ash and silt, the slate like matrix in which the fossils are presented, is frequently intersected by natural calcite mineral formations, deposited by water.
- Generally preserved with intact articulation, the bones of K. hui present grey to black in colouration – the result of permineralisation whereby inorganic minerals of the surrounding substrate replace organic minerals comprising the delicate bones.
- Commonly found with ventral presentation – stomach uppermost – the skull is displayed from beneath – most desirous are dorsal presentations whereby the skull exhibits cranial elements including the large orbits and are particularly sought after by collectors.
- Previously something of an enigma - these fascinating reptiles have only recently (2006) been distinguished according to gender.
- The discovery of two specimens preserved carrying unborn babies enabled scientists to differentiate between the acknowledged sexual dimorphism.
- Additionally, a second question as to whether the species gave birth to live young, or laid eggs, was answered – babies were delivered (presumably under water) akin to Ichthyosaurs.
- Gender differentiation hinges principally upon characteristics of the humerus and ulna, with males having more robust elements.
- However, until sexual maturity is reached, gender cannot be determined, so sexing of specimens is restricted to adults.
- Maximal maturity peaked at a length of 12” (30cm) approximately, from tip of snout to end of tail – rarely examples are found exceeding this.
- Very few life representations of K. hui are available so in 2006, Triassica commissioned paleo artist Gareth Monger to produce a new work, representing the latest understanding of the species morphology.
- Triassica own the original artwork – prints available from the Natural History Museum.
- Reference to the holotype V952 (Institute of Vertebrate Paleontology & Paleoanthropolgy, Beijing, China) & other described specimens GXD7601,GXD7613, GXD7621, Guizhou Province Museum, China (ref; Functional Morphology & Ontogeny of Keichousaurus hui [Reptilia, Sauropterygia] K. Lin, O. Reippel 1998).
Mike Holmes BSc.DipBiolSci.CertNatSci.CertContSci.MRI.AMBCS.AMIBiol.FZS
Original artwork commissioned by Triassica - genuine Keichousaurus hui fossils supplied by triassica.com