Spatangus purpureus Müller3D ModelNoAI
Group: sea urchin
Age: Recent
Location: Cres, Croatia
Specimen size: 10 x 9 cm
Inventory Number: 5540
Description: The first irregular sea urchins (echinoids) appeared in the Early Jurassic, presumably due to increased predation pressure on benthic animals and/or a change in feeding habits. The second major radiation of irregular sea urchins occurred in the early Palaeogene, when the so-called ‘sand dollars’ (Clypasteroida) evolved. This corona of the now extant genus Spatangus shows many of the characteristics of irregular sea urchins: a vertically flattened corona, a pronounced bilateral symmetry, shortened ambulacral fields, a shift of the oral and occipital apertures towards the edges of the corona, a feeding furrow and weaker, thinner spines.
Photo: Ajda Lovše. Model: Marko Vrabec. Description: Luka Gale.
Comments