Family MEGATHYRIDIDAE Dall, 1870
Introduction
Occurence: Upper Cretaceous to Recent.
Diagnosis
Loop composed of descending branches only, passing in most advanced genus through stages correlative with Gwynia, Argyrotheca, and Megathiris, lower genera not completing the series; lophophore trocholophorous to ptycholophous; posterior margin strophic or nearly so; spicules absent or very freebly developed; dental plates absent. From Moore (1965: H830).
Diagnosis References
History of changes
Note that this list may be incomplete for dates prior to September 2013.
| Published | As part of group | Action Date | Action Type | Compiler(s) |
|---|---|---|---|---|
| 12-Feb-2010 | (import) |