Cuticular hydrocarbon composition and phenotypic variability in sympatric populations of Ixodes ricinus ticks from Poland

Abstract

Gas chromatography of cuticular hydrocarbons was used to assess genetic similarity and heterozygosity between 18 sympatric populations of adult Ixodes ricinus ticks collected from Poland. Sixteen n-alkanes, 45 monomethylalkanes, and 36 dimethylalkanes were identified. Forty-one compounds were detected in 90% of the specimens and nine hydrocarbons were present in all the specimens studied. Visual inspection of chromatograms revealed major differences in the relative abundance of hydrocarbons between populations of I. ricinus. The average proportion of heterozygotic hydrocarbons was 50.68%, while the average genetic similarity among all populations was 0.967. Two other methods were used to measure the intrapopulation variability: the number of isomeric forms for each hydrocarbon and the range of hydrocarbon abundance. It was found that some hydrocarbons manifested an unexpectedly high number of isomeric patterns, such as nonacosane (21 patterns), triacontane (23), pentacosane (26), and hexacosane (28). Our data suggest that I. ricinus ticks from Poland consist of several interbreeding, non-isolated populations, with a high degree of genetic flow between them.

Hydrocarbons catalysed by TmCYP4G122 and TmCYP4G123 in Tenebrio molitor modulate the olfactory response of the parasitoid Scleroderma guani

“…The differences between the two studies might be because of biological factors (geographical population and developmental stage), abiotic factors (food and rearing condition), and the sensitivity of GC‐MS. The differences between the two studies also suggest that variation in the relative abundance of cuticular HCs might be of use in distinguishing geographically distinct T. molitor populations, as has been previously demonstrated for ticks (Estrada‐Peña et al , ), termites (Dronnet et al , ) and flies (Ye et al , ).…”

Evidence of female sex pheromones and characterization of the cuticular lipids of unfed, adult male versus female blacklegged ticks, Ixodes scapularis

“…Only 6 linear, saturated hydrocarbons were identified in I. scapularis whole body extracts ranging from lengths of 10–18 carbons. The short chain alkene 1-heptene, previously undocumented in Ixodes species, was also identified (Estrada-Peña et al 1994; Tkachev et al 2000). Since metastriate ticks actively hunt for or ambush hosts, they are more susceptible to environmental conditions than prostriate ticks, which quest and usually remain on or near plants that offer shelter and protection.…”

“…There is currently no evidence that cuticular hydrocarbons function as pheromones in ticks (Estrada-Peña et al 1994). The cuticular hydrocarbons identified in I. scapularis whole body extracts are less diverse and shorter overall than those reported in metastriate ticks.…”

“…In view of the widespread use of cuticular lipids in sexual communication in other arthropods, we also investigated potential sex differences in the cuticular lipids of adult I. scapularis . Only a few studies have been conducted on cuticular lipids of prostriate ticks, i.e., I. persulcatus and I. ricinus (Estrada-Peña et al 1994; Tkachev et al 2000; Dusbábek et al 2001). …”

A unique phenomenon of oral-anal contact between ticks observed in two tick species <i>Ixodes ricinus</i> and <i>Dermacentor reticulatus</i>

“…Many components with the same compounds present at different concentrations have also been detected in cuticular extracts from Prostriata ticks, i.e. I. ricinus [19], and I. scapularis [20], and from Metastriata ticks, i.e. in some species from the genera Dermacentor, Hyalomma, Rhipicephalus, and Amblyomma [13].…”