Of fungi and ticks: Morphological and molecular characterization of fungal contaminants of a laboratory-reared Ixodes ricinus colony

Ticks Tick Borne Dis. 2021 Sep;12(5):101732. doi: 10.1016/j.ttbdis.2021.101732. Epub 2021 May 3.


Establishing and maintaining tick colonies in the laboratory is essential for studying their biology and pathogen transmission, or for the development of new tick control methods. Due to their requirement for very high humidity, these laboratory-bred colonies are frequently subject to fungal contamination. In the present study, we aimed to identify the fungal species that contaminated a laboratory-reared colony of Ixodes ricinus through microscopic observation and molecular identification. We identified three different taxa isolated from the ticks: Aspergillus parasiticus, Penicillium steckii, and Scopulariopsis brevicaulis. These three species are usually regarded as environmental saprophytic molds but both direct and indirect evidence suggest that they could also be considered as entomopathogenic fungi. Although we do not have any direct evidence that the fungi isolated from I. ricinus in this study could cause lethal infections in ticks, we observed that once infected, heavy fungal growth coupled with very high mortality rates suggest that studying the entomopathogenic potential of these fungi could be relevant to biological tick control.

Keywords: Aspergillus parasiticus; Ixodes ricinus; Penicillium steckii; Scopulariopsis brevicaulis; Tick; Tick colony.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Aspergillus / isolation & purification
  • Fungi / isolation & purification*
  • Ixodes / microbiology*
  • Laboratories
  • Penicillium / isolation & purification
  • Tick Control / trends

Supplementary concepts

  • Aspergillus parasiticus
  • Penicillium steckii