Principia (alga)
Encyclopedia
Principia is a genus of alga that has been placed in the coralline stem group on the basis of it slightly-differentiated thallus; it forms an "intermediate" between Hortonella
, Neoprincipia
and Archaeolithophyllum
.
Hortonella
Hortonella is a genus of alga that has been placed deep in the coralline stem group on the basis of its scarcely-differentiated thallus....
, Neoprincipia
Neoprincipia
Neoprincipia is interpreted as the earliest crown-group red alga....
and Archaeolithophyllum
Archaeolithophyllum
Archaeolithophyllum is a genus of conceptacle-bearing red alga that falls in the coralline stem group that somewhat resembles Lithophyllum; it's the only Palaeozoic coralline to bear clear conceptacles, although the earlier Graticula does bear reproductive structures.It mineralized using aragonite...
.