Difflugia pyriformella   Chardez, 1983

Diagnosis: Shell perfectly pyriform, with a clear neck, narrow and cylindrical, often slightly narrowed at its base. Shell embedded with small mineral elements, there are almost always larger mineral elements surrounding the base of the neck, the shell is circular in section.

Dimensions: Chardez (1983): Shell length 100-125 µm; diameter 50-60 µm; neck height 25-35 µm; pseudostome diameter 17-26 µm. Beyens and Chardez (1994) measured six specimens from Devon Island, Arctic Canada, with a length of 78-90 µm (n=6).

Ecology: Freshwater, in sediment. This species is known from two ponds in Belgium, Sarrazines and Eplatis, Domaine des Epioux, Belgian Ardennes (Chardez 1982), from Ireland (Beyens & Chardez 1984), the Shetlands (Beyens et al. 1988) and Devon Island, Canada (Beyens and Chardez 1994).

Remarks: Beyens and Chardez (1994): “This species, despite its shape, cannot be confused with D. pyriformis due to its small size and is distinguished from other varieties of the group by its general morphology. The shape of the collar distinguishes this species from Difflugia pyriformis var. longicollis. The species included under the name Difflugia longicollis Gassowsky by Ogden and Hedley in their atlas published in 1980 corresponds perfectly to D. pyriformella Gassowsky, in which the collar is very stretched and not very clear and which measures on average 94 um according to this author.”