thorns or granules. A very characteristic structure is seen in diadematoids, where the shaft is built up of whorls and appears segmented (the spine is then termed verticilate). Spines are generally ...
Some cidaroids evolved large glandiform spines. Spine structure is variable and provides important taxonomic characters. The shaft can be smooth or ornamented by ribs, thorns or granules. In ...
Results that may be inaccessible to you are currently showing.
Hide inaccessible results