The retractable proboscis of acanthocephalans is equipped with hooks for attachment to the intestine definitive host. Throughout their evolutionary history, have developed a variety ways maximize anchoring host gut and avoid dislodgement. Hooks vary in size shape along longitudinal axis proboscis, texture, structure, hardness as well contribution absorption nutrients. also chemical composition,...

This study describes the parasitic fauna of Oxydoras niger from the Coari Lake, tributary of the medium Solimões River, State of Amazonas, Brazil, and the relationship between the number of Monogenoidea and the condition factor. From a total of 27 examined fish, 70.3% were parasitised by at least one parasite species as follows: Ichthyophthirius multifiliis (Protozoa), Chilodonella sp. (Protozo...

The genus Gigantorhynchus (type species = G. dubius Sapelnikov & Malygina, 1977, by original designation) was established by Sapelnikov & Malygina (1977: 62) for a distinctive fossil brachiopod from Eastern Alai (Southern Tien Shan, Kyrgyzstan) which subsequently served as type of a subfamily (Gigantorhynchinae Savage 1996). However, the name Gigantorhynchus was preoccupied by a living worm gen...

Body wall muscles of an acanthocephalan Macracanthorhynchus hirudinaceus were studied by means of scanning and light microscopy and intracellular recording of potentials. Three types of spontaneous potential changes were found: larger (L) potentials which usually exhibited overshoot and were as large as 65 mV; smaller symmetric (A) potentials approximately 15 mV in amplitude; and even smaller a...