Experimental & Applied Acarology

, Volume 21, Issue 10, pp 685–696

Evidence for the reproductive isolation of Dermacentor marginatus and Dermacentor reticulatus (Acari: Ixodidae) ticks based on cross-breeding, morphology and molecular studies

  • M. Zahler
  • R. Gothe

DOI: 10.1023/A:1018412803414

Cite this article as:
Zahler, M. & Gothe, R. Exp Appl Acarol (1997) 21: 685. doi:10.1023/A:1018412803414


The species status of Dermacentor marginatus and Dermacentor reticulatus was evaluated by scanning electron microscope (SEM) examination of adult ticks, cross-breeding experiments and molecular biological analysis of eggs derived from transspecific pairings. The SEM investigations including the morphometric quantification of phenotypic features resulted in an unequivocal differentiation of adult D. marginatus and D. reticulatus ticks. The cross-breeding experiments demonstrated that irrespective of whether female ticks of both species were applied with con- or transspecific male ticks or without males to sheep, they engorged and laid eggs. The larvae, however, developed only in eggs which originated from conspecific matings. A nested polymerase chain reaction (PCR) of the second internal transcribed spacer (ITS2) using the DNA of eggs from transspecific pairings and sequencing of the PCR products revealed two different genotypes. The genotypes of eggs originating from D. marginatus and D. reticulatus females of these pairings differed. However, the eggs deposited by D. marginatus always possessed the same two genotypes as did the eggs produced by D. reticulatus. These results argue for a strict reproductive isolation of D. marginatus and D. reticulatus and, therefore, for a separate species status.

Dermacentor marginatusDermacentor reticulatusnested PCRinternal transcribed spacerscanning electron microscopycross-breeding

Copyright information

© Chapman and Hall 1997

Authors and Affiliations

  • M. Zahler
    • 1
  • R. Gothe
    • 1
  1. 1.Institute for Comparative Tropical Medicine and ParasitologyUniversity of MunichMunichGermany