Leuckart's Cyclops
Mesocyclops leuckarti
Leuckart's Cyclops is a widespread planktonic copepod primarily found in the open water zones of lakes and ponds. It is characterized by a slender body shape and relatively long first antennae. This species plays a crucial role in aquatic food webs, serving as a link between phytoplankton and fish.
Details
Identification
Slender body; 17-segmented first antennae; characteristic spines on the terminal segment of the fourth pair of swimming legs.
Social behavior
Solitary, but occurs in high individual densities within the plankton.
Diet
Omnivorous to predatory; feeds on algae, protozoa, and smaller zooplankton such as rotifers.
Hunting strategy
Active seizing of prey organisms in the open water.
Spawning substrate
Eggs are carried in sacs on the body; nauplii hatch directly into the open water.
Overwintering
Overwintering usually occurs as a late copepodid stage in the sediment (dormancy).
Ecology
Ecological role
Important consumer in the pelagic zone and a significant food source for planktivorous fish.
Natural predators
Juvenile fish, predatory insect larvae (e.g., Chaoborus), and larger zooplankton.
Competitor species
Other cyclopids and calanoid copepods.
Ecosystem service
Regulation of algal and protozoan populations; base of the food chain for commercial fish species.
Threats
Eutrophication, pesticide input, and acidification of water bodies.
Scientific profile
Profile
Distinguishing features
The first pair of antennae (A1) consists of 17 segments; the terminal segment of the A1 has a hyaline membrane with a characteristic deep notch. The connecting plate of the fourth pair of swimming legs (P4) features acute, spine-like outgrowths. The terminal segments of the P4 endopodites are elongated.
Reproduction
Exclusively sexual reproduction. Females carry two symmetrical egg sacs on the urosome. Development proceeds through six naupliar and five copepodid stages.
Role in food web
Important secondary consumer in the pelagic food web; regulates populations of rotifers and smaller crustaceans and serves as energy-rich prey for fish.
Protection & threats
Status not on standard scale
Main threats
Severe acidification of water bodies (pH < 5), toxic algal blooms (cyanobacteria), and invasive species that alter the food web structure.