Hagenococcus aggregatus nov. gen. et sp., a microscopic, colony-forming alga from the 410-million-yr-old Rhynie chert
Krings, Michael; Kerp, Hans; Taylor, Edith L.; Harper, Carla J.
Photoautotrophic microorganisms were likely abundant in the Early Devonian Rhynie ecosystem; however, documented evidence of these life forms is rare. Hagenococcus aggregatus nov. gen. et sp. occurs in the Rhynie chert matrix as solitary cells, dyads, triads, linear, decussate, and isobilateral tetrads, sarcinoid packets, short filaments, irregular aggregations, and colonies. Individual cells are 15–40(–>55) μm in diameter. While it cannot be ruled out that H. aggregatus is a large cyanobacterium, affinities to the Chlorophyta or Streptophyta are far more likely. Some of the cells contain a prominent, spheroid inclusion which might represent the pyrenoid. Hagenococcus aggregatus expands our knowledge of the diversity of primary producers in Paleozoic non-marine ecosystems.