White Cyclops
Macrocyclops albidus
Macrocyclops albidus is a large, predatory copepod inhabiting a wide range of freshwater environments globally. It is recognized for its characteristic jerky swimming motion and its ability to prey on organisms such as mosquito larvae. Due to its wide distribution and ecological plasticity, it is a vital component of limnic food webs.
Details
Identification
Robust body shape; short first antennae; terminal segments of the 5th legs with three spines/setae; often whitish-transparent.
Social behavior
Solitary, but forms dense populations when food availability is high.
Diet
Predatory; feeds on rotifers, small crustaceans, protozoa, and newly hatched insect larvae.
Hunting strategy
Active ambush predator that detects prey via mechanical stimuli and strikes rapidly.
Spawning substrate
Eggs are carried in two sacs attached to the female's abdomen until the nauplii hatch.
Overwintering
Overwinters as adults or late copepodid stages in sediment or deeper water layers.
Ecology
Ecological role
Important predator in the micro-food web; regulates populations of microorganisms and serves as fish prey.
Natural predators
Juvenile fish, predatory aquatic insects (e.g., backswimmers), water mites.
Competitor species
Other large cyclopoid species such as Macrocyclops fuscus.
Ecosystem service
Biological control of disease vectors (mosquito larvae).
Threats
Eutrophication, pesticide runoff into water bodies, habitat loss.
Scientific profile
Profile
Distinguishing features
17-segmented first antennae reaching the end of the second thoracic segment. The terminal segment of the antennule bears a smooth or finely serrated hyaline membrane. Inner margins of the caudal rami are bare. The fifth leg (P5) consists of two distinct segments, with the distal segment bearing three appendages (spines/setae).
Reproduction
Sexual reproduction; females carry two lateral egg sacs. Development proceeds through 6 naupliar and 5 copepodid stages to the adult.
Role in food web
Secondary consumer; important link in the littoral food web; significant for the biological control of mosquito larvae.
Protection & threats
Status not on standard scale
Main threats
Habitat loss due to shoreline stabilization and macrophyte removal, input of insecticides from agriculture, and increasing desiccation of small water bodies.