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JORDAENS KURT; RIEL PATRICK VAN; GEENEN SOFIE; VERHAGEN RON; BACKELJAU THIERRY 《Journal of Molluscan Studies》2001,67(2):161-167
Body pigmentation is a popular taxonomic marker in slugs to
discriminateclosely related species. However, the genetic background
ofbody pigmentation is known only for a few species, while inmany
others body pigmentation is influenced by age, food and/orclimate. In
this study, we investigated the effects of differentfood items on
body pigmentation expression in two selfing pulmonategastropods,
Arion (Carinarion) silvaticus and Arion (Carinarion)
fasciatus.Both species mainly differ in the distribution of
yellow-orangegranules on the body, which in A. fasciatus are
concentratedin lateral bands, and in A. silvaticus are evenly
scattered.Animals were raised individually under the same conditions,
whilethey laid eggs as a consequence of selfing. This F1 generation
wasafterwards divided into two groups, which were fed with different
fooditems. A diet of carrot, lettuce or paper had no effect on the
distributionof the yellow-orange granules in A. silvaticus, but
provokeda loss of the yellow-orange lateral bands in A. fasciatusso that externally these F1
specimens became similar to A. silvaticus.In both species, a
diet of nettle resulted in a strong yellow-orangepigmentation, which
often formed yellow-orange lateral bands.These results indicate that
food can probably influence the'species-specific' body pigmentation in
Carinarion, and thusquestion the reliability of colour traits to
distinguish A.silvaticus and A. fasciatus. (Received 5 May 2000; accepted 29 September 2000) 相似文献
120.
This paper examines the variability of the genital characters
ofHelix pomatia and H. lucorum. Some of these
characters are commonlyused to distinguish the two closely related
species. Variationswithin and between populations are also
investigated. The highvariability of these characters can frequently
lead to identificationerrors, especially in eastern Europe. Correct
identificationof these edible snails is also of commercial
importance, differentspecies having a different price. The reciprocal
nature of themale parts of the genitalia and the bursa stalk and
diverticulumcomplex is pointed out. A possible function of the
diverticulumis suggested on the basis of size relations between
genitalsystem features. (Received 12 August 1999; accepted 11 April 2000) 相似文献