Parasitology, Harold W. Manter Laboratory of
Date of this Version
4-1972
Abstract
Thirteen of 16 Siren intermedia collected in Union County, Illinois, were infected with from two to 49 specimens of Fessisentis fessus Van Cleave, 1931. There are no previous reports of identified specimens of Acanthocephala from Siren. This is also the first report of F. fessus since the original description and represents new host and locality records. Old siren harbor more and larger specimens than do young siren. Intensity of infection and host age do not, however, relate to variability of other morphological features. Two paratypes, the original description, and specimens from siren form the basis for redescription of Fessisentis fessus. It is now realized that the trunk of females may be up to 52 mm long and unlike all other species of the genus it possesses a subterminal genital pore. It is also known that lemnisci of males seldom reach the anterior testis and that proboscis hooks may be in as many as 21 longitudinal rows. Contrary to the original description, F. fessus possesses two retinacula. The proboscis receptacle departs from usual acanthocephalan morphology in consisting of two muscular layers of tubular bundles with contractile fibers at the periphery enclosing a central area of noncontractile cytoplasm. Fessisentis necturorum Nickol, 1967, and F. vancleavei Haley and Bullock, 1953, also possess two retinacula and have proboscis receptacles identical in construction to those of F. fessus. Fessisentis and Fessisentidae are redescribed to conform to this additional information. Acanthocephalus vancleavei Hughes and Moore, 1943, agrees with Fessisentis as redescribed with the exception of cement gland number. One male specimen was reported to have a cement gland number atypical of both Acanthocephalus and Fessisentis. It is felt that this deviation should not be emphasized to the point of obscuring unique features shared with species of Fessisentis. Because of transfer of this species to Fessisentis, a new name, F. friedi, is proposed for F. vancleavei Haley and Bullock, 1953. Richard Heard has collected Fessisentis necturorum near Athens, Georgia, from larval Ambystoma opacum. This represents additional knowledge of host and geographical distribution.
Comments
Published in the Journal of Parasitology (April 1972) 58(2): 282-289. Copyright 1972, the American Society of Parasitologists. Used by permission.