dcsimg

Description

provided by iArczoo

Very clear and practically color-less

license
cc-by-3.0
compiler
Ershova, Elizaveta
partner site
iArczoo

Diagnostic Description

provided by iArczoo

Very similar species to M. pusillus some authors argue that it is the same species.
Differences: longer A1, which reach the end of the caudal rami. Narrower third segment of the exopodites of P2, P3 and P4 and narrower and more finely serrated apical spines. The right appendage in P5 in males is equal to 1/2 of the left appendage.

license
cc-by-3.0
compiler
Ershova, Elizaveta
partner site
iArczoo

Distribution

provided by iArczoo

North Pacific, Sea of Japan, Sea of Okhotsk, Bering Sea, all Arctic Seas and Antarctic waters, North Sea, Norwegian Sea

license
cc-by-3.0
compiler
Ershova, Elizaveta
partner site
iArczoo

Habitat

provided by iArczoo

Epi-bathypelagic, occurs at all depths, prefers cold waters. Migrates to greater depths in the winter

license
cc-by-3.0
compiler
Ershova, Elizaveta
partner site
iArczoo

Life Cycle

provided by iArczoo

Mass reproduction starts before the start of the spring bloom after the vertical migration of adult males and females to the surface. Most likely life cycle takes a year to complete. Reproduction to some extent takes place all year, most likely due to the ability to feed on microzooplankton and detritus.

license
cc-by-3.0
compiler
Ershova, Elizaveta
partner site
iArczoo

Look Alikes

provided by iArczoo

Microcalanus pusillus G. O. Sars, 1903

license
cc-by-3.0
compiler
Ershova, Elizaveta
partner site
iArczoo

Morphology

provided by iArczoo

Females: Very small copepods with a characteristic, very round and plump, body shape. Maximum width of the cephalothorax is in the top third, slightly narrowed at the head, which has a triangular shape. The corners of the last thoracic segment carry short rounded projections, which are curved at the base. Apical spines of the exopodites of P2, P3 and P4 serrated. A1 reaches the end of the caudal rami. P5 absent.

Males:
Characteristic body shape even more pronounced than in females. Head has a triangular shape, rounded projections at the corners of the last thoracic segment are very pronounced. P5 asymmetrical - the left appendage is much larger and composed of 6 segments, the last of which is the smallest. The right appendage is three-segmented, almost half as as long as the left one, the smallest appendage is the third.

license
cc-by-3.0
compiler
Ershova, Elizaveta
partner site
iArczoo

Size

provided by iArczoo

Females: 0.60-0.70 mm
Males: 0.70 mm

license
cc-by-3.0
compiler
Ershova, Elizaveta
partner site
iArczoo

Trophic Strategy

provided by iArczoo

Morphology of feeding appendages suggests that this species feeds on phytoplankton, as well as microzooplankton and detritus in deep water layers during winter and early spring.

license
cc-by-3.0
compiler
Ershova, Elizaveta
partner site
iArczoo

Distribution

provided by World Register of Marine Species
Gulf of St. Lawrence (unspecified region); lower St. Lawrence estuary, Saguenay Fjord; downstream part of middle St. Lawrence estuary
license
cc-by-4.0
copyright
WoRMS Editorial Board
bibliographic citation
North-West Atlantic Ocean species (NWARMS) North-West Atlantic Ocean species (NWARMS)
Contributor
Mary Kennedy [email]

Habitat

provided by World Register of Marine Species
upper epipelagic of the Gulf and estuary
license
cc-by-4.0
copyright
WoRMS Editorial Board
bibliographic citation
North-West Atlantic Ocean species (NWARMS) North-West Atlantic Ocean species (NWARMS)
Contributor
Mary Kennedy [email]