Drepanidotaenia watsoni sp. n. (Cestoda, Hymenolepididae) from the Wild Turkey of Arkansas

Abstract

Drepanidotaenia watsoni, a new hymenolepidid tapeworm from the small intestine of the wild turkey (Meleagris gallopavo), is described and compared with all known members of the genus. A key is presented to differentiate the 14 described species of the genus Drepanidotaenia. Distinguishing characteristics of D. watsoni are a flared region in the anterior end of the strobila, ten rostellar hooks, and the presence of hairlike projections on the outer embryonic membrane of mature oncospheres. Data are presented concerning the incidence and distribution of this cestode among wild turkeys of Arkansas. The reported cestodes of turkeys in the United States comprise 13 known species in six genera. Although the majority of these tapeworms infect both domestic and wild turkeys (Meleagris gallopavo), a few have been recorded from only the wild host (Reid, 1962). Little study has been given to helminths infecting wild turkeys, and it was not until 1963 that Maxfield et al. reported on the incidence and distribution of gastrointestinal helminths among wild turkeys of the southeastern United States. In that survey 32% of 31 turkeys were found infected with a hymenolepidid tapeworm which was limited in distribution to four counties in Arkansas (Arkansas, Dallas, Grant, and Lee counties). These collections were made during the spring gobbler hunts in April 1961. The cestode did not conform morphologically to known genera of the family Hymenolepididae previously found in turkeys. Additional viscera from 43 wild turkeys were obtained during the first half of the annual hunt (1-4 April 1963). These included 17 wild turkeys from Arkansas County, 19 from Grant County, four from Hot Springs County, and three from Lee County. Viscera were preserved in toto in a solution of alcohol and glycerine as described in Maxfield et al. Received for publication 25 January 1965. * This study was sponsored by the Southeastern Cooperative Wildlife Disease Study, School of Veterinary Medicine, University of Georgia through funds made available by the Eightyeighth Congress of the United States and administered through the Bureau of Sport Fisheries and Wildlife of the Department of the Interior through Contract No. 14-16-0008-676. Additional funds were provided by Grant No. G12,999 from the NSF. t Journal Series Paper No. 410, College Experiment Station, University of Georgia, Athens. (1963). Since tapeworms obtained by this method were unsuitable for detailed microscopic studies, four freshly killed birds were obtained from Grant County during the second half of the annual hunt (17-18 April 1963). Approximately 60 specimens with scolices intact were collected and fixed in steaming 10% formalin. Upon return to the laboratory, only four of the fragile scolices could be recovered, the others having disintegrated in transit. D scription of the adult tapeworm was based upon four scolices and 15 hematoxylinstained whole mounts. With exception of scolices, a minimum of 25 measurements was made of each structure. Drawings were facilitated with a Wild drawing tube and measurements were made with a calibrated ocular