Lectotype

Where the original diagnosis is without illustrations or is accompanied by figues based on two or more specimens, the first subsequent author is at liberty to select from these cotypes a type for the old species, adhering, as far as can be ascertained to the intention of the original author. Such a type speciment is to be designated as a lectotype...

The lectotype and paratype, which are before me, are both iron-stained, predominantly internal composite molds of left valves in a fine-grained, white quartzite matrix.

Lectotype designation is justified under article 74.1.1 of the ICZN (1999) in order to fix the status of this specimen as the sole name-bearing type of this species.