University of Kansas Publications
Museum of Natural History
Volume 9, No. 13, pp. 385-388
May 12, 1958
BY
J. KNOX JONES, JR.
University of Kansas
Lawrence
1958
University of Kansas Publications, Museum of Natural History
Editors: E. Raymond Hall, Chairman, Henry S. Fitch,Robert W. Wilson
Volume 9, No. 13, pp. 385-388
Published May 12, 1958
University of Kansas
Lawrence, Kansas
PRINTED IN
THE STATE PRINTING PLANT
TOPEKA, KANSAS
1958
27-3033[Pg 387]
BY
J. KNOX JONES, JR.
In the autumn of 1952, I obtained a southern bog lemming,Synaptomys cooperi, at Rock Creek State Fish Hatchery, DundyCounty, in extreme southwestern Nebraska. This locality of recordis the westernmost for the species in North America. Subsequently,I reported this specimen in the literature (Univ. Kansas Publ., Mus.Nat. Hist., 7:486, 1954), provisionally assigning it to Synaptomyscooperi gossii, the subspecies occurring in eastern Nebraska.In late November of 1956, J. R. Alcorn collected three additionalbog lemmings at the Rock Creek Hatchery.
These specimens from Dundy County represent a relict populationthat differs in several characteristics from S. c. gossii, and thatdiffers also from all other subspecies of the species. This relict populationis, therefore, here given subspecific recognition.
Type.—Adult female, skin and skull, University of Kansas Museum ofNatural History no. 51617, from Rock Creek State Fish Hatchery, 5 mi. N,2 mi. W Parks, Dundy County, Nebraska; obtained November 1, 1952, byJ. Knox Jones, Jr., original no. 995.
Distribution.—Known only from the type locality.
Diagnosis.—Size large for the species, both externally and cranially; dorsalpelage dark; nasals broadly flared anteriorly (especially broad in relation tonasal length); auditory bullae small; molariform tooth-rows and incisiveforamina long.
Measurements (in millimeters).—External measurements of the type specimen,followed by those of another adult female (KU 72603), are: Totallength, 141, 145; length of tail-vertebrae, 24, 21; length of hind foot, 20, 20;length of ear from notch, 11, 12. The type specimen weighed 46.3 grams.Cranial measurements were taken in the manner described by Wetzel (Jour.Mamm., 36:2-3, 1955) except that he did not record the occipitonasal length.These cranial measurements of the type and KU 72603 are: Occipitonasallength, 30.2, 29.8; condylobasilar length, 27.2, 27.1; zygomatic breadth, 18.1,17.9; lambdoidal breadth, 14.2, 13.8; length of nasals, 8.2, 8.3; breadth ofnasals, 4.2, 4.0; length of rostrum, 6.6, 6.6; breadth of rostrum, 6.1, 5.9; breadthof upper incisors, 4.6, 4.2; length of maxillary tooth-row, 8.5, 8.4; length ofincisive foramen, 5.8, 5.5; interorbital breadth, 3.1, 3.5.