This is a spine-based taxon. No spines are definitely associated with tests. However, Vadet (2000, p. 71) attributed interambulacral fragments of Serpianotiaris [described as Zardinitiaris flexuosa] on the basis that the spines of Cidaris fexuosa were crenulate. As Hagdorn (1995) has shown, the spines of Serpianotiaris are very different from those named flexuosa and there is no justification for this association of plates and spines.
Zardini (1976) provides the most thorough description and illustration of the type species.
Zardini, R. 1976. Fossili di Cortina: Atlane degli Echinodermi Cassiani Trias Medio superiore dell regione Dolomitica attorno a Xortina d'Ampezzo. Luglio, 29 pp, 22 pls.
Vadet, A. 2001. Revision des echinides de Saint Cassian et evolution des echinides post-carboniferes. Memoires de la Societe Academique du Boulonnais 20, 1-116.