Strigeids from Texas Mink with Notes on the Genus Fibricola Dubois

Abstract

In the past year the writer has twice had the opportunity to examine specimens of Mustela vison, killed by automobiles on highways near Houston, Texas. In both instances the animals were obtained a few hours after death. These mink were found to be harboring strigeids of two species, Neodiplostomum lucidum Larue and Bosma, 1927, and Fibricola cratera (Barker and Noll, 1915) Dubois, 1937. Twelve flukes from the small intestine of one of the animals examined are referred to N. lucidum which has been described and reported from the opossum, Didelphis virginiana. Since the worms from mink agree very closely with material from local opossums, no description is deemed necessary. Fibricola cratera was found in the small intestine of both animals examined; there were about thirty worms in each host. Since some of the specimens do not conform with published descriptions of F. cratera, a further study of this and other described members of the genus seemed warranted. Hemistomum cratera was described from the muskrat, Ondatra zibethica, by Barker and Noll (1915). Dubois (1932) created the genus Fibricola with cratera as the type species. It has been reported subsequently from the mink in Ontario by Law and Kennedy (1932); from the raccoon in Iowa by Morgan and Waller (1940) and in Michigan by Chandler and Rausch (1946); from the skunk, Mephitis nigra, in Michigan by Chandler and Rausch (1946); and from the opossum in Georgia and Tennessee by Byrd, Reiber, and Parker (1942) and in Michigan by Chandler and Rausch (1946). The life cycle was described by Cuckler (1940) who obtained the adults experimentally in cats, rats, and mice. Cuckler reported natural infections in muskrats, brown rats, meadow mice, and short-tailed shrew in Nebraska. In the cratera from mink examined by the writer the holdfast organ is more variable in size and shape than has been noted by previous workers. Byrd, Reiber, and Parker (1942), in describing cratera from the opossum, stated that the holdfast was elongated to transversely oval and figured a specimen with an elliptical holdfast organ. Dubois (1937), working with material of Law and Kennedy (1932) from muskrat, described the holdfast organ as circular. Examination of specimens of cratera from raccoons (identified by Morgan and Waller and by Chandler and Rausch), from experimentally infected cats of Cuckler, from skunk (identified by Chandler and Rausch), and from opossums (identified by Chandler and Rausch) revealed