Mastogloia lucayensis guide
  1. Valves elliptic
  2. Apices apiculate
  3. Valve with large hyaline areas
  4. Single paraxial row of pores
  5. Partectae nearly square

Most of the valve face is unornamented. Only the raphe, a longitudinal row of pores along each side of the raphe, and a marginal zone of areolae are present. Valves are elliptic, with apiculate apices and nearly square partecta. Under SEM, striae can be observed to be alveolate.