Satyrization without evidence of successful insemination from interspecific mating between invasive mosquitoes

Abstract

Previous research has documented low frequencies of interspecific mating in nature between the invasive vectors Aedes aegypti and Aedes albopictus. It is also known that heterospecific male accessory gland substances transferred during mating sterilize A. aegypti but not A. albopictus females, leading to satyrization, a form of reproductive interference. This paper demonstrates that satyrization of A. aegypti by A. albopictus may occur without evidence of successful insemination. Our results show that A. aegypti females, previously exposed to A. albopictus males, are rendered refractory to subsequent conspecific mating even though their spermathecae contain no heterospecific sperm. Additional experiments demonstrating transfer of labelled semen from A. albopictus males to A. aegypti females and low production of viable eggs of females housed with conspecific males, following exposure to A. albopictus males, confirm higher incidences of satyrization than expected, based on heterospecific insemination rates. We conclude that frequencies of satyrization based on detection of interspecific sperm in spermathecae may underestimate the impact of this form of reproductive interference.

Zika and chikungunya: mosquito‐borne viruses in a changing world

“…aegypti female fecundity, and that this may occur in nature at very low rates (1.6–3% of field‐collected females in Florida). However, one study showed that satyrization may occur even without successful insemination . More research is required in order to understand if this phenomenon plays a significant role in the displacement of Ae.…”

Rapid evolution and the genomic consequences of selection against interspecific mating

“…Our ability to only detect large effect genes or attribute outlier loci to adaptation is an issue that plagues both candidate gene approaches and reduced-representation sequencing (Bierne, Welch, Loire, Bonhomme, & David, 2011;Chenoweth & Blows, 2006). While previous studies may show the genetic architecture or candidate genes associated with postmating female choice (Lawniczak & Begun, 2004), the genetic basis for the interspecific mating avoidance of female A. aegypti is likely prior to copulation particularly as copulation even without sperm migration can cause female sterility (Carrasquilla & Lounibos, 2015). Therefore, this behaviour may involve other genes not currently identified.…”

Reproductive interference in insects

“…Extreme costs need not only arise from damage or predation though. Heterospecific matings can render females sterile, as in female Aedes aegypti Linnaeus (Culicidae) mosquitos when they mate with male Aedes albopictus Skuse (Culicidae) (Nasci et al, 1989; see also Carrasquilla & Lounibos, 2015). Similarly, females of the dermestid beetle Trogoderma glabrum Herbst (Dermestidae) often failed to mate with a conspecific after mating with the heterospecific Trogoderma inclusum LeConte (Dermestidae), effectively sterilising them (Vick, 1973).…”