CASSIDULIDAE AGASSIZ & DESOR, 1847

Souto, Camilla, Mooi, Rich, Martins, Luciana, Menegola, Carla & Marshall, Charles R., 2019, Homoplasy and extinction: the phylogeny of cassidulid echinoids (Echinodermata), Zoological Journal of the Linnean Society 187, pp. 622-660 : 650-651

FAMILY CASSIDULIDAE AGASSIZ & DESOR, 1847

Emended diagnosis: Cassiduloids with monobasal apical system. Pore-pairs conjugated by slight or sharp furrow. Ambulacral plates following posterior petals usually wider than long, with pores placed towards adradial suture. Periproct supramarginal, equant or transverse. Plates framing periproct not bending inwards; interambulacral plates adoral to periproct convex. Naked zone present in ambulacrum III and interambulacrum 5; pits small or absent. Phyllodes medium-sized to long; occluded plates absent or scattered. Peristome equant or transverse; (sub)pentagonal. Interambulacral basicoronal plates 1 and 4 narrower than interambulacral basicoronal plate 5. Bourrelets poorly developed, bulged or pointed; formed by accretion of stereom onto basicoronal plates. Sphaeridia placed near buccal pores. Oral tubercles much larger than aboral tubercles. From living species of Cassidulus and Rhyncholampas : periproctal membrane with two rows of medium-sized plates and few small plates; anal opening on aboral edge. Tridentate pedicellariae short, broad.

Type genus: Cassidulus Lamarck, 1801

Included genera based on present analysis: Cassidulus , Paralampas and Rhyncholampas .

Misclassified cassidulids in need of reassignment after additional studies: C.? kieri , Rl.? carolinensis , R l.? c o n r a d i, R l.? c o o k e i, R l.? d a r a d e n s i s, Rl.? grignonensis and Rl.? tuderi .