C. mespiliformis, 136 µm high

Cucurbitella mespiliformis Penard, 1902

Diagnosis: Shell ovoid, with distinct anterior addition of an apertural collar, dark grey or opaque in color, robust; outline regular, body constructed of small to medium, angular mineral grains. Organic cement seldom seen as surface feature. Diameter of collar just less than half diameter of shell, composed of small mineral grains, 3-5-lobed. Aperture a small circular opening recessed within the collar, on a level with the main body wall. Single large, vesicular nucleus with a large central nucleolus, one or more contractile vacuoles, symbiotic zoochlorellae in cytoplasm; numerous, short, lobose pseudopodia.

Dimensions: Penard 120-140 µm; Cash 116-140 µm; my measurements 110-132 µm long.

Ecology: Freshwater; on waterplants and in debris.
I found this species in ‘t Hol in Kortenhoef, the Bert Bospad in Loosdrecht and Den Treek in Amersfoort. At the latter location, it was abundant. This species has never been recorded by Hoogenraad & De Groot (1940), despite their intensive survey of testate amoebae in the Netherlands.

Cucurbitella mespiliformis nucleus
Cucurbitella mespiliformis nucleus
Nucleus, 29 µm, and the same nucleus in DIC
Cucurbitella mespiliformis, aperture or diaphragm
Cucurbitella mespiliformis, fourlobed collar.
Cucurbitella mespiliformis, filled with zoochlorellae; 110 µm long
Cucurbitella mespiliformis, 132 µm
Recent posts

Difflugia symoensi

Difflugia symoensi, from Chardez, 1964 Difflugia symoensi  Chardez, 1964 Diagnosis: Test bag-shaped, with pseudostome almost as wide as the width of the test; fundus rounded.

Read More »

Difflugia tenuis

Difflugia tenuis, from Penard, 1890 Difflugia tenuis  (Penard, 1890) Chardez, 1983 Diagnosis: Test cylindrical or slightly pyriform, fundus often more angular then rounded, very transparent

Read More »

Difflugia gigantea

Difflugia gigantea (left) compared with other species to show its size Difflugia gigantea Schlumberger, 1845 Diagnose: test ovoid, elongated, narrowed anteriorly, almost pyriform, sometimes slightly

Read More »

Difflugia masaruzzii

  Difflugia manicata, test and nucleus – after Van Oye, 1958   Difflugia masaruzzii  Van Oye, 1958 Diagnosis: Test more or less ovoid with lateral

Read More »