Archaeolithophyllum

Archaeolithophyllum is a genus of conceptacle-bearing red alga that falls in the coralline stem group. It somewhat resembles Lithophyllum.^[1][2]

Archaeolithophyllum Temporal range: Pennsylvanian PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Clade:	Archaeplastida
Division:	Rhodophyta
Class:	Florideophyceae
Stem group:	Corallinales
Family:	†Archaeolithophyllaceae
Genus:	†Archaeolithophyllum Johnson, 1956
Species
A. delicatium Johnson, 1956 A. missouriensum Johnson, 1956 (type)

As of today, Archaeolithophyllum is the only Palaeozoic coralline to bear clear conceptacles,^[3] although the earlier Graticula does bear reproductive structures.^[4]

It mineralized using aragonite.^[3] Its conceptacles are cone-shaped protrusions that extend outwards from the thallus surface and have a single central opening.^[5] It probably encrusted muddy or sandy surfaces.^[5]

See also

• Coralline algae#Evolution
• Other stem-group corallines:
  • Arenigiphyllum (Ordovician)
  • Petrophyton (Ordovician : Caradoc)
  • Graticula (Silurian : Wenlock)
  • Halysis (Ordovician)
  • Archaeolithophyllum (Pennsylvanian)
  •  ?Maimonachaetetes (Mississippian)
  •  ?Palaeoaplysina (Pennsylvanian – Permian; possibly an animal)
  •  ? Solenoporaceae (Ordovician)