The Occurrence of Cyclops kolensis Lilljeborg (Copepoda, Cyclopoida) 
in North America 1 
Edward B. Reed 2 
Cyclops kolensis was named by Lilljeborg in 
1901 ; in the intervening 60 odd years, it has 
been infrequently reported in the literature. 
Kozminski (1933) noted that although C. 
kolensis is one of the most widely distributed 
species "in our region’’ it had been forgotten 
until recent years when he and Rzoska (1930) 
independently mentioned it in revisions of cer- 
tain groups of Cyclops. 
Judging from the list of synonyms prepared 
by Lindberg (1957) the name C. kolensis 
rarely has been incorrectly applied to other 
species. However, the reverse has occurred rather 
frequently; that is, animals which are actually 
C. kolensis have been assigned to other species. 
Apparently the most common misidentification 
has been to mistake C. kolensis for C. vicinus 
Uljanin. Less frequently it has been confused 
with C. strenuus; for example, Kiefer (1929) 
included kolensis as a doubtful synonym of 
strenuus. 
The first evidence of C. kolensis on the North 
American continent appeared in some of the 
collections of the Canadian Arctic Expedition of 
1913-1916. Marsh (1920) recorded finding in 
collections made at Bernard Harbour, N.W.T., 
and at Cape Collinson, Alaska, a number of 
freshwater cyclops with a spine formula of 
2, 3, 3, 3 but which in other features agreed with 
the description of C. strenuus. Marsh assigned 
his Canadian and Alaskan specimens to C. 
vicinus Uljanin 1875, noting that, because C. 
kolensis Lilljeborg and C. minutus Lilljeborg 
have the same formula of spines as does C. 
vicinus on the outer margins of the terminal 
segments of the exopodites of the swimming 
legs, he could see no reason for regarding these 
as distinct species (Marsh, 1920:11). Marsh 
1 This is part of a study financed by National Sci- 
ence Foundation grant G 24954. Manuscript received 
April 21, 1967. 
2 Department of Zoology, Colorado State Univer- 
sity, Fort Collins, Colorado 80521. 
also regarded C. scutifer as a synonym of C. 
strenuus on the basis that both have a spine for- 
mula of 3, 4, 3, 3, thus obscuring the fact that 
both species occur in arctic North America. 
Kozminski (1936) questioned the assign- 
ment of the North American specimens to C. 
vicimis, remarking that the furcal rami of C. 
scutifer and C. kolensis are similar, whereas the 
rami of C. vicinus are quite different from those 
of C. scutifer. Because Marsh had made his diag- 
nosis chiefly on the basis of the spine formula, 
Kozminski (1936:225) believed it quite likely 
that the animals in question were C. kolensis. 
Yeatman (1944) re-examined Marsh’s col- 
lections, which had been deposited in the U. S. 
National Museum. He noted that the Alaskan 
specimens differed from C. vicinus in propor- 
tions of the furcal rami and in the relative 
lengths of some of the terminal furcal setae. 
Yeatman further noted that the shapes of the 
4th and 5th thoracic segments of Marsh’s speci- 
mens differed from C. scutifer, in which these 
segments are expanded. C. kolensis does not 
have expanded thoracic segments; the thoracic 
segments of C. vicinus are strongly expanded. 
However, in spite of these differences Yeatman 
(1944:84) believed that Marsh had correctly 
assigned his specimens to C. vicinus. 
Rylov (1948:198), in giving the known dis- 
tribution of C. kolensis, considered Marsh’s 
specimens to belong to that species. 
Lindberg (1956) revived the question and 
proposed Cyclops kolensis alaskaensis as a nomen 
novum for the Alaskan specimens. He noted 
(p. 117) that neither the form of the 4th and 
5th thoracic segments nor the proportions of the 
furca as figured by Yeatman conform to the 
description of C. vicinus Uljanin. Lindberg 
(1957) further contrasts C. k. alaskaensis with 
C. k. kolensis on the basis of the figures and 
discussions of Marsh and Yeatman. 
Until recently the only specimens of C. 
kolensis from North America were apparently 
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