Erugomicula bidens (Penard, 1902)
Basionym: Difflugia bidens Penard, 1902
Diagnosis: Test ovoid, compressed in cross-section, relatively smooth; fundus usually with 2-3 small spines; pseudostome large, circular, without collar; nucleus finely granulated, large, sometimes with a globular structure inside.
Dimensions: Penard (1902): 250-270 µm long; Nasser et al., (2021): 219 – 341 μm; my measurements: 270-366 µm.
Ecology: I found several specimens in detritus from the bottom of ditches in the nature reserve Naardermeer in the Netherlands (GPS 52.281278 – 5.118853). This species has also been recorded for some other European countries and for Canada.
Remarks: This species has usually two spines, hence the name bidens.