Arion rufus: Rowson, B.

The cellular composition, the morphology of the components, and the screening function and evolutionary changes of the light-insulating apparatus of the camera-like eye of the terrestrial gastropod pulmonate mollusk Arion rufus were studied and evaluated using light and electron microscopy. According to all the considered characteristics, the light-insulating apparatus of A. rufus is typical for terrestrial pulmonate mollusks. Evolutionary transformations of the light-insulating apparatus, caused by the change in the mollusks' environment, are insignificant and affect the cellular composition, the morphology of pigmented cells and the isolation of the light-sensitive parts of photoreceptor cells from each other.

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Chemical Defense of Lupins. Mollusc-Repellent Properties of Quinolizidine Alkaloids

Zeitschrift für Naturforschung C ◽

10.1515/znc-1984-0608 ◽

1984 ◽

Vol 39 (6) ◽

pp. 553-558 ◽

Cited By ~ 33

Author(s):

Michael Wink

Keyword(s):

Natural Products ◽

Lactuca Sativa ◽

Helix Pomatia ◽

Free Food ◽

The Other ◽

Quinolizidine Alkaloids ◽

Feeding Response ◽

Artificial Diets ◽

Arion Rufus

Polyphagous molluscs such as Helix pomatia and Arion rufus generally do not feed on plants containing alkaloids. Of 19 species tested 10 species were totally avoided, the other 9 species were less attacked than Lactuca sativa, which was readily taken. Plants containing quinolizidine alkaloids were studied in detail. Those species with the α-pyridone alkaloids cytisine and N-methylcytisine were avoided to a higher extent than plants with lupanine as the major alkaloid. Since the repellency observed could be due to other natural products present in the plants besides the alkaloids, the feeding response of Helix pomatia was tested on artificial diets containing quinolizidine alkaloids in various concentrations as the only variable. If the snails had the choice they clearly preferred alkaloid-free food or a diet with only low alkaloid concentrations. Half-maximal repellency of cytisine is less than 2 mᴍ, of sparteine 1-5 mᴍ, and of lupanine 1-8mᴍ. Since the in vivo concentrations of sparteine, cytisine, and lupanine are equal to or higher than the inhibitory concentrations required it is concluded that quinolizidine alkaloids constitute a potential antimolluscan principle of legumes.

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Nematodes associated with terrestrial slugs in the Edmonton region of Alberta, Canada

Journal of Helminthology ◽

10.1017/s0022149x20000838 ◽

2020 ◽

Vol 94 ◽

Author(s):

T. Brophy ◽

R.J. Mc Donnell ◽

D.K. Howe ◽

D.R. Denver ◽

J.L. Ross ◽

...

Keyword(s):

Caenorhabditis Elegans ◽

Ribosomal Dna ◽

Sequence Data ◽

Nematode Species ◽

Species Level ◽

Molecular Sequence Data ◽

Molecular Sequence ◽

C Elegans ◽

Facultative Parasite ◽

Arion Rufus

Abstract A survey of nematodes associated with terrestrial slugs was conducted in residential gardens, nurseries, greenhouses and agricultural sites located in and around Edmonton, Alberta, Canada. A total of 2406 slugs were collected from 82 sites. Slugs were decapitated and cadavers were incubated for two weeks, with emerging nematodes removed and processed for identification. Nematodes were identified using molecular sequence data for the 18S ribosomal DNA. Nematodes were recovered from 20 of the 82 sites surveyed, with 24.4% of the slugs infected with nematodes. A total of seven nematodes were identified to species level, including Caenorhabditis elegans, Panagrolaimus papillosus, Pellioditis typica, Pelodera pseudoteres, Rhabditella axei, Rhabditoides inermiformis and Phasmarhabditis californica. An additional four specimens were identified to genus level, including Oscheius sp. (9), Pristionchus sp., Rhabditis sp. and Rhabditophanes sp. (1). The two most common nematode species were C. elegans and P. pseudoteres. The facultative parasite, P. californica, was recovered from a single Arion rufus specimen, collected from a seasonal nursery. To our knowledge, this study represents the first survey of slug-associated nematodes in Canada.

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