Compared to other cyclopoids, Ectocyclops phaleratus has an abdomen that appears very wide compared to its cephalothorax. It is only found in South-Norway, most often in small nutrient rich localities.

Key characteristics

The habitués of Ectocyclops phaleratus is similar to Paracyclops affinis which is smaller and has a less robust form. Compared to other cyclopoids, its abdomen appears very wide compared to its cephalothorax. The short antennae have 10 segments, which is a criteria that distinguish E. phaleratus from the two species of the genus Paracylops, having respectively eight and 11 segments. Its colour is a dark reddish brown.

Female: Length 0.9–1.1 mm

Male: Length 0.8 mm

Ecology and distribution

E. phaleratus is found in slightly less than 4 % of the waterbodies, situated south of Dovre and mainly in the lowland (>500 m a.s.l.). It occurs with its highest frequency in waterbodies <10 ha. It seems to be acid sensitive and is rare at pH<6. Electrolyte rich habitats seems to favour the species.

    pH
    Ledningsevne (m S/m)
    Conductivity (m S/m)
    Innsjøareal (da)
    Surface area (da)
    Høyde over havet (moh.)
    Elevation (m a.s.l.)

Look alikes

Paracyclops affinis