Order Phacopida, Suborder Calymenina, Superfamily Calymenoidea,
Geologic Age: Middle Ordovician
Trilobite is 34 mm long
Sugar River Formation, Trenton Group, Sackets Harbor, New York
Remarks: Four different trilobite species are Flexicalymene cf senaria,
hence the cf moniker. A Flexicalymene senaria from the famous Walcott
Rust quarry is most pustulose, while another
not so much. A third is rather effaced like seen here.
Clearly, some revisions are in order. Note that this Flexicalymene also
has prominent duckbilled rostrum simuilar to Spathaclaymene.
Also note the deep furrows typical of calymenids.
Also see: American
Note the pronounced protruding rostrum: