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Diacyclops (cyclopoid copepod)

Diacyclops spp. · Aquatic life

Diacyclops (cyclopoid copepod): Under the microscope

Under the microscope · Photo: Aleksandr Novikov / CC BY

NativeCopepod

Also called Cyclopoid copepod, Diacyclops thomasi, Diacyclops bicuspidatus, Cyclops bicuspidatus thomasi

How to identify Diacyclops (cyclopoid copepod)

  • Teardrop shaped body about 1 to 1.5 mm with a forked tail
  • Short antennae and two egg sacs on females
  • Darting swimmer, often pale or slightly tan
  • Separated from other cyclopoids by the lab using leg and tail details

Similar species

Acanthocyclops and Cyclops look almost the same by eye; calanoid copepods have long antennae and one egg sac.

Profile

SeasonPeaks in spring; juveniles often rest in the bottom mud through midsummer and return in fall.
StartsCool water, often active under ice
DepthOpen water, deeper in summer
How it spreads or reproducesSexual reproduction; paired egg sacs; juveniles rest in sediment
HabitatOpen water of lakes and reservoirs, especially cooler, deeper water; also ponds.

Why it matters in a lake

A common lake copepod that eats rotifers, small water fleas and algae, and is important food for kokanee, trout and perch.

Where it is found

  • Idaho: Common
  • Oregon: Common
  • Wyoming: Common

Classification

KingdomAnimalia
PhylumArthropoda
ClassCopepoda
OrderCyclopoida
FamilyCyclopidae
Scientific nameDiacyclops spp.

More copepod

Copepod naupliiAcanthocyclops (cyclopoid copepod)Leptodiaptomus (calanoid copepod)Mesocyclops (cyclopoid copepod)Eucyclops (weed bed copepod)Macrocyclops (large cyclopoid copepod)Cyclops (cyclopoid copepod)Skistodiaptomus (calanoid copepod)Hesperodiaptomus (mountain lake copepod)Epischura (large calanoid copepod)

Browse all aquatic life in the Species Database

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