Oleiformis carmelae  Soler-Zamora et al., 2023

Diagnosis: Elongated shell with an almost perfectly circular section. The shell is larger towards its middle part, giving an inflated appearance; rounded fundus. Short neck in comparison to other members of Cyphoderiidae. Rounded pseudostome with a thin organic layer surrounding it. Elliptical scales placed next to each other in a structured fashion; each scale is surrounded by six pores.

Measurements. length 169.92–190.83 μm, width 67.44–83.14 μm, pseudostome large axis 22.51–27.85 μm, and scales from the middle of the shell 2.65–2.99 × 1.93–2.26 μm (N = 13).

Habitat: River sediment. Type locality: Morollón River, Fuente de la Gitana recreational area, La Peza, Spain (37º51ʹN2º47ʹW).

Differential diagnosis: It can be confused with O. major because of their similar shell shape. O. carmelae is smaller, with relatively larger scales. It differs also genetically in both COI and SSU.

Intraspecific variability. Some individuals have a slightly more pointed fundus.