Abstract: ABSTRACT: In 1984, work on the parasite population and community ecology in the pulmonate snail, Helisoma anceps, was initiated in Charlie's Pond (North Carolina). Similar research on Physa gyrina was started in 1986. When study in the pond began in 1984, 8 species of larval trematodes were being shed from H. anceps. By far, the dominant species was Halipegus occidualis, with prevalen...

Unsaturated aliphatic isobutylamides from Asteraceae, Rutaceae and Piperaceae are potential agents to control schistosomiasis. Affinin (N-isobutyl-2,6,8_decatrienamide) from Heliopsis longipes has strong molluscicidal activity against Physa occidentalis (LD5e ca 100 PM) and the cercariae of the fluke. The amide has also been shown to be present in Wedelia parviceps flowers.

Halipegus eccentricus is a common hemiurid trematode in the eustachian tubes of North America frogs. However, the life cycle of this species has never been completely elucidated. Studies on H. eccentricus suggest that it has a 3-host life cycle. Here, we show through fieldwork and host specificity experimental infections that the life cycle of Halipegus eccentricus utilizes 4 hosts. Metamorphos...

In the course of several trips to Peru I had the opportunity of collecting topotypic specimens of Biomphalaria andecola (Orbigny, 1835), B. helophila (Orbigny, 1835), B. pucaraensis (Preston, 1909), Drepanotrema limayanum (Lesson, 1830), D. kermatoides (Orbigny, 1835), and Lymnaea viatrix Orbigny, 1835, besides B. tenagophila (Orbigny, 1835), Helisoma trivolvis (Say, 1817), H. duryi (Wetherby, ...

The cosmopolitan freshwater pulmonate snail Physa acuta hybridizes readily with Physa carolinae in the laboratory, although their F1 progeny are sterile. The two species differ qualitatively in shell shape, the former bearing a more globose shell and the latter more fusiform. We performed a hybridization experiment, measuring a set of 14 traditional (linear) and landmark-based shell morphologic...