Plascocista

Plascocista Leidy, 1879 (ref. ID; 3686) reported year? (ref. ID; 1618)

Order Euglyphida: Family Assulinidae (ref. ID; 6795 original paper)

See Placocista

[ref. ID; 1618]
Test ovoid, hyaline, compressed; lenticular in cross-section; with oval or subcircular siliceous scales; aperture wide, linear, with flexible undulate borders; nucleus large, posterior; often with zoochlorellae; filopodia branching and many, generally arising from a protruded portion of cytoplasm; fresh water. (ref. ID; 1618)

[ref. ID; 3686]
Shell colourless; ovoid, oval in transverse section; composed of oval shell-plates, siliceous spines sometimes present at lateral margins; aperture lenticular, bordered by organic cement. (ref. ID; 3686)

  1. Plascocista spinosa (Carter, 1865) (ref. ID; 3686) reported year? (ref. ID; 1618) or Leidy, 1879 (ref. ID; 1401) reported author and year? (ref. ID; 6795)

Plascocista spinosa (Carter, 1865) (ref. ID; 3686) reported year? (ref. ID; 1618) or Leidy, 1879 (ref. ID; 1401) reported author and year? (ref. ID; 6795)

Descriptions

Margin of test with spines, either singly or in pairs; in Sphagnum. (ref. ID; 1618)
The shell is ovoid and composed of approximately four hundred, oval shell plates. Siliceous spines project from the lateral margins, either singly or in pairs. The arrangement of these spines is such that they are easily broken. The aperture is an elongate slit, whose outline is often irregular due to the arrangement of the shell plates, concave in lateral view and surrounded by a thin collar of organic cement. Different types of spines figured by Cash (1915), but this appears to be the only variable character. (ref. ID; 3686)

Measurements

116-174 by 70-100 um. (ref. ID; 1618)
Shell length 143-160, breadth 87-110; diameter of aperture 58-79; shell plates length 15-18, breadth 7-9; length of spines 17-29 um (n=6). (ref. ID; 3686)