|
Diagnosis
|
Clade of Echinacea with:
- apical disc relatively small; hemicyclic to dicyclic. Periproct subcircular with smooth rim;
- ambulacra trigeminate to polygeminate, with arbaciid style plate compounding; only one element in each compound plate expanded and extending from adradial to perradial suture and bearing primary tubercle; other elements are demiplates;
- Primary tubercles minute; those of ambulacral and interambulacral zones similar in size; generally perforate and often crenulate, but small size and poor preservation;
- Peristome relatively small; buccal notches distinct.
|
|
Range
|
Cretaceous, Europe, North America, Middle East, North Africa. |
| Type |
Pedinopsis |
| Classification and/or Status |
Carinacea, stem group Echinacea, |
| Remarks |
Closely resembling certain arbaciids but differing from them in having perforate and crenulate tubercles. Emiratiidae have perforate tubercles but differ in having a monocyclic apical disc, whose inner edge is notched by periproctal plates. Emiratiidae also differ in having simple diadematid plate compounding. |
