Netzelia mulanensis, from Meisterfeld et al., 2005

Netzelia mulanensis (Yang et al. 2005) Gomaa et al., 2017
Difflugia mulanensis Yang, Meisterfeld, Zhang and Shen, 2005

Diagnosis: Shell yellowish to brown and semitransparent. It looks like a spherical to elliptical vase with a large apertural collar. The test is 1.16–1.61 times longer than the diameter of the collar, symmetrical in longitudinal and apertural view. It consists of a large circular collar and a tall shell belly with a distinct neck. The aperture is circular. The collar is dish-like or low-funnel-shaped, forming an angle of 115°–160°; the apertural funnel has a height of 11–24% of the total length, and its basal (neck) diameter is 0.39–0.74 times the collar diameter; its margin is ragged. The belly (or main body) is circular in cross section, the narrowest cross section (neck) lies just below the collar, gradually expanding (7°–17°); the maximal width is normally located in the posterior 22–31% of the shell, with its greatest diameter 0.73–1.06 times the collar diameter. The aboral end is always rounded, never with a protuberance, horn or spine. The shell wall is composed of small angular particles and medium flattish pieces of quartz or other forms of silica (xenosomes), including pieces which appear to be parts of the frustules of centric diatoms, fitted together to give a smooth surface and a regular outline. The collar is made of smaller flattish particles. No obvious cement structures are recognizable in the scanning electron microscope.

Dimensions: Length 90-128 µm, breadth 61-81 µm, diam. collar 65-95 µm, collar height 11-29 µm; diam. aperture 27-47 µm

Ecology: Freshwater; China, Lake Mulan.

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