world of amoeboid organisms

Puytoracia bergeri
Puytoracia bergeri, from Nicholls, 2006

Puytoracia bergeri   Nicholls, 2006

Diagnosis: Shell an oblong flattened cylinder, with rounded anterior and posterior ends. An invaginated pseudostome located in an anterio-ventral position. The main test body covered with scales of three basic shapes and sizes: large (5–8 x 8–11 µm) elliptical scales over the dorsal surface and the posterior two-thirds of the ventral surface; tiny elliptical scales (about 1–1.5 x 1.5–2 µm) interspersed between the large scales; elliptical scales of an intermediate size (about 2–3 x 3–5 µm) occur in the anterior region of the test (dorsal, ventral and lateral surfaces). Pseudostome deeply invaginated and its wide (6–10 µm) apertural rim ornamented with a fourth scale type: 2–4 rows of small, specialized circular-to-elliptical scales with a thickened and pointed spine projecting from the scale margin, resulting in a ‘‘toothed’’ appearance to the rim of the pseudostome.

Dimensions: Length 49–60 µm; width 29–39 μm.

Ecology: Between Sphagnum occurring in a black spruce (Picea mariana) wetland located in the Turtle River – Rainy River drainage basin at 49105010.400N; 9211000.400W, approximately 200km NW of the city of Thunder Bay, Ontario, Canada.

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