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Mesocyclops edax
Mesocyclops edax
Mesocyclops edax Mesocyclops edax
Phylum Arthropoda
Subphylum Crustacea
Class Maxillopoda
Subclass Copepoda
Order Cyclopoida
Family Cyclopidae
Fifth leg is two segmented with two long terminal setae on distal segment   Serrated hyaline membrane present on distal,or end, segement of first antennae   First antennae, or antennules, have 17 segments
Additional Pictures
Geographic Distribution

M. edax
is widespread throughout eastern and central North America and is also found in the tropics (3).

Reported Habitats

M. edax
exhibits diel vertical migration, however, there is preference for warmer waters and migrations are normally limited to above the thermocline (2).

Food and Feeding Behavior

M. edax
feeds on rotifers, cladocera, both calanoid and cyclopoid nauplii and copepodites, as wells as ciliate protozoans (4). This species has been observed eating D. floridanus whole by severing part of the carapace and sucking out the body contents (5).

Reproductive Habits

In southern lakes, females are ovigerous nearly all yearround. Whereas in northern, colder temperature lakes, M. edax completes two to three discrete generations between April and October and will then diapauses for the winter (3).


M. edax
is preyed upon by alewife (1).


M. edax
swims in a hop-sink fashion (4).


(1) WELLS, L. 1970. Effects of Alewife predation on zooplankton populations in Lake Michigan . Limnol. and Oceanogr.       15: 556-565.

(2) MARARCOGLIESE, D. and G. E. ESCH. 1992. Alterations of vertical distribution and migration of zooplankton in       relation to temperature. American Midland Naturalist. 128: 139-155.

(3) ALLEN, J. D. 1984. Life history variation in a freshwater copepod: Evidence from population crosses. Evolution. 38:       280-291.

(4) WILLIAMSON, C. E. 1980. The predatory behavior of Mesocyclops edax : Predator preferences, prey defenses, and       starvation-induced changes. Limnol. and Oceanogr. 25: 903-909.

(5) CONFER, J. L. 1971. Intrazooplankton predation by Mesocyclops edax at natural prey densities. Limnol. and       Oceanogr. 16: 663-666.

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Additional Notes
Present in Barbadoes Pond, Madbury, NH
Barcode: Ribosomal DNA-28S D3 expansion segment