The World of Protozoa, Rotifera, Nematoda and Oligochaeta
Quadrulella
Quadrulella Cockerell, 1909 (ref. ID; 2290, 3686)
[ref. ID; 1923]
Shell normally pyriform, with siliceous plates. This genus can be considered a subgenus of Nebela. The distinction between siliceous and calcareous plates is very easily seen with the polarizing microscope. The endogenous siliceous pates always remain black in crossed nicols. (ref. ID; 1923)
[ref. ID; 2290]
Shell colourless, ovoid, composed of quadrangular shell plates arranged without overlapping; aperture oval. (ref. ID; 2290)
[ref. ID; 3686]
Shell colourless; ovoid; composed of quadrangular siliceous shell-plates; aperture terminal, oval. (ref. ID; 3686)
Quadrulella acuminata Van Oye, 1957 (ref. ID; 2235 original paper)
Quadrulella Debonti Van Oye, 1959 (ref. ID; 2236 original paper)
Plates very transparent, usually regularly arranged in transverse and longitudinal series. Many varieties, some being short, other long, others curved. Habitat Sphagnum and moss, generally submerged. (ref. ID; 1923)
The shell is colourless, ovoid or pyriform and composed of quadrangular, siliceous shell plates. It is compressed laterally especially in the apertural region. The shell plates are usually arranged in a regular manner, often in rows, with smaller plates close to the aperture. The aperture is oval, often concave in lateral view, and surrounded by a thin collar of organic cement. (ref. ID; 3686)
Comments
Differences in the breadth of specimens was recorded by Cash (1909), whilst Deflandre (1936) redescribed Q. symmetrica and three varieties, var. longicollis, var. irregularis and var. curvata. (ref. ID; 3686)
Measurements
Length 68-150 um. (ref. ID; 1923)
Length of shell 72-103; breadth of shell 36-52; depth of shell 27-35; diameter of aperture 18-22 um (n=12). (ref. ID; 3686)