The Tadpoles of Bufo cognatus Say
BY
HOBART M. SMITH
University of Kansas Publications
Museum of Natural History
Volume 1, No. 3, pp. 93-96, 1 figure in text
August 15, 1946
UNIVERSITY OF KANSAS
LAWRENCE
1946
University of Kansas Publications, Museum of Natural History
Editors: E. Raymond Hall, Chairman, Donald S. Farner, Donald F. Hoffmeister
Volume 1, No. 3, pp. 93-96
Published August 15, 1946
University of Kansas
Lawrence, Kansas
PRINTED BY
FERD VOILAND, JR., STATE PRINTER
TOPEKA, KANSAS
1946
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The Tadpoles of Bufo cognatus Say
By
HOBART M. SMITH
The tadpoles of this species have been described by Bragg (Copeia,1936: 14-20, figs. 1-13; Amer. Midl. Nat., 18:273-284, figs. 1-5,1937). The drawings and descriptions of the mouthparts, however,appear to have been taken from dried, or immature, or transformingindividuals, for they do not agree among themselves nor dothey agree with larvae obtained in the field and now in the Museumof Natural History of the University of Kansas.
At hand are two series of tadpoles of this species; one series wascollected July 2, 1938, 1.5 miles east of Meade County State Park,Kansas, and the other lacks data. The second lot contains numeroussizes of tadpoles from 14 mm. to 31 mm., and several transformingspecimens which clearly possess the pattern so typical of this species.
Fig. 1.—Mouthparts of a tadpole of Bufocognatus. Disk widely spread.
Approximately × 45.
Mouthparts in both series (consisting all told of about 200 specimens)are fairly constant except in the transforming and extremelyyoung specimens. The accompanying figure shows them as seenwith the mouth disk widely spread. The indentations at the cornersof the mouth in the papillary fringe are more prominent when themouthparts are less extended. The outer row of teeth of the lowerlabium is sometimes a little shorter or longer than the figure shows,but the average is about as indicated. The extent of the medialedge of the papillae on the lower labium varies somewhat; in some,[Pg 96]the papillae barely reach the level of the ends of the outer row ofteeth, while in others they overlap the ends slightly.
Measurements agree with those given by Bragg, except that appearanceof the hind legs occurs at about 15 mm.; the fore legs appearat about 28 mm. A pattern recognizably similar to that of the adultis evident at about 20 mm.
These tadpoles show such a striking similarity to those referred byWright to Bufo compactilis Wiegmann (Proc. U. S. Nat. Mus., 74:4,pl. 5, fig. 6, 1929) that their conspecificity is suggested. If on theother hand, the specimen figured by Wright is properly identified,then the two species must in reality be very closely related. A directcomparison of positively identified tadpoles of each species is muchto be desired.
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