No abstract

No abstract

The surface ultrastructure of Probolocoryphe uca (Digenea: Microphallidae), recovered from a rat experimentally fed on crabs, Nanosesarma minutum (Brachyura: Grapsidae), naturally infected with the metacercariae, was studied by scanning electron microscopy. The flukes were leaf-like, ventrally concave and pyriform or ovoid in outline. The anterior end was modified into a sucker-like organ, comprising a protrusible disc-shaped structure surrounded by single-pointed spines. This organ is probably involved in the attachment and feeding process in a manner similar to the action of the oral suckers. Apart from the sucker-like organ, the entire tegumental surface was covered with triangular spines with multi-pointed tips. Ciliated, dome-shaped papillae were observed, singly or in groups, arranged symmetrically on the sucker-like organ and around the oral and ventral suckers. Kuwait Bay constitutes a new geographical record and the crab N. minutum is a new second intermediate host record for P. uca.

The structure and formation of metacercarial cysts in the trematode family Microphallidae Travassos 1920Desiccation survival of populations of the entomopathogenic nematodes Steinernema feltiae and Heterorhabditis megidis from Greece and the UK Preliminary biochemical characterization of faeces from uninfected rats and rats infected with the tapeworm, Hymenolepis diminuta

A new echinostome cercaria, Cercaria kuwaitae XI sp.n., from the prosobranch gastropod Cerithidea cingulata (Gmelin) from Kuwait Bay is described. The new cercaria is characterized by 23 collar spines and primary excretory tubules with distinct diverticula. The cercaria encysts in the snail host and is similar to those of Acanthoparyphium sp. The surface topography of the redia, cercaria and metacercarial cyst wall is studied by scanning electron microscopy. This is the first echinostome cercaria to be recorded in a gastropod from the Arabian Gulf region.Key words: Digenea -Cercaria kuwaitae XI sp.n. -Acanthoparyphium sp. -ultrastructure -Cerithidea cingulataKuwait Bay alcohol (AFA) and staining in acetocarmine. Measurements are in micrometres, the range with the mean in parentheses, and were taken from 20 vitally stained refrigerated specimens. Figures were drawn with the aid of a camera lucida from vitally stained specimens. For SEM, living larval stages were fixed in a solution containing 4% formaldehyde and 1% glutaraldehyde in 0.1 M phosphate buffer (pH 7.2) at 4°C. Following the appropriate buffer wash, the specimens were post-fixed in 1% osmium tetroxide in the same buffer for 5 min at 4°C, dehydrated in a series of anhydrous acetone and critical-point dried. The specimens were coated with gold and then examined in a Jeol JSM-6300 scanning electron microscope.