Genetic differentiation and species status within the snail leech Glossiphonia complanata aggregate (Hirudinea : Glossiphoniidae) revealed by RAPD analysis
R. Verovnik et al., Genetic differentiation and species status within the snail leech Glossiphonia complanata aggregate (Hirudinea : Glossiphoniidae) revealed by RAPD analysis, ARCH HYDROB, 144(3), 1999, pp. 327-338
Randomly amplified polymorphic DNA (RAPD) markers were employed to analyse
genetic differentiation and taxonomic structure within the snail leech Glos
siphonia complanata species aggregate. Three morphological types of snail l
eeches, whose taxonomic validity was formerly mainly distrusted, occur thro
ughout Europe. Six individuals of each morphotype from four locations in Sl
ovenia were investigated. At two locations all three morphotypes occurred s
yntopically, enabling the determination of reproductive isolation. PCR ampl
ification with eleven decamer random primers yielded 177 reproducible marke
r fragments, only one of which was monomorphic in all specimens. Genetic si
milarity within morphotypes was substantially higher than within samples fr
om the same locality but consisting of different morphotypes. The estimated
nucleotide diversity within morphotypes (0.7-2.1 %) was tower than the nuc
leotide divergence between them (5.1-8.3 %). UPGMA clustering and principal
coordinate analysis revealed three groups concordant with the identified m
orphotypes. They were tentatively assigned to the taxa Glossiphonia complan
ata (LINNAEUS), G. concolor (APATHY) and G. nebulosa KALBE. Reproductive is
olation between them is suggested by the presence of RAPD fragments specifi
c to each taxon, and by the absence of common fragments in syntopic populat
ions of the three taxa. This is strong support for the hypothesis that exte
rnally very similar and anatomically nearly identical glossiphoniids belong
to different biological species.