Morphological variation between populations of the expanding ectoparasitic deer ked Lipoptena cervi (Diptera: Hippoboscidae) in Fennoscandia

Research output: Contribution to journalArticle


We examined morphological and genetic differences among Fennoscandian deer ked (Lipoptena cervi L, Hippoboscidae) populations with varying expansion history: the eastern population (Finland) has expanded rapidly, whereas the western population is divided into an old and relatively stationary sub-population in Sweden and a newly established and more expansive sub-population in Norway. The genetic analysis suggests that the distinct populations represent a single species. Individuals from expansive populations were characterized by a large body size, relatively large and robust thorax shape, and wing shape with an exaggerated basal posterior margin. Yet, there was no among population variation in relative wing size or its elongated shape after variation in overall size was controlled for. Although certain size and shape variables showed thermal sensitivity, the degree of plasticity did not differ between the populations. In general, we observed that shape is more sensitive to external thermal conditions at the pupal stage than size per se, with the thermal sensitivity of the latter depending on the trait under examination. We conclude that the possible adaptive value of morphological differences relies on variation in survival during the off-host life stages or short-distance flight to reach a susceptible host instead of long-distance dispersal ability.


  • Mervi Jaakola
  • Meri Ojanen
  • Eija Hurme
  • Marko Mutanen
  • Niklas Wahlberg
  • Panu Välimäki
  • Arja Kaitala
External organisations
  • University of Oulu
  • University of Turku
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Ecology


  • Development temperature, Geometric morphometrics, Invasive species, Phenotypic plasticity, Pupal phase, Pupiparous, Range expansion, Temperature-size rule, Viviparous
Original languageEnglish
Pages (from-to)432-448
Number of pages17
JournalBiological Journal of the Linnean Society
Issue number2
Publication statusPublished - 2015 Oct 1
Publication categoryResearch