Differences in sperm storage and remating propensity between adult females of two morphotypes of theAnastrepha fraterculus(Diptera: Tephritidae) cryptic species complex

Abstract

The South American fruit fly, Anastrepha fraterculus, is a complex of cryptic species composed of at least seven morphotypes. Some of them, such as the Peruvian and Brazilian 1 morphotypes (which include Argentinean populations), exhibit strong pre-copulatory isolation, yet it is possible to obtain heterotypic crosses when forcing copulation of adults under laboratory conditions. The cross involving Peruvian males and Argentinean females produces F1 offspring with reduced viability in terms of egg hatch. This low hatchability could be caused by a reduced amount of sperm transferred to and stored by females mated with heterotypic males, which in turn could affect their post-copulatory behaviour. To test these hypotheses, we investigated sperm transfer and female mating and remating behaviour for homotypic and heterotypic crosses between adults of two morphotypes (Brazilian 1 [Argentina] and Peruvian [Peru]) of the A. fraterculus cryptic species complex. As reported before, Argentinean males and females mated earlier in the day than the other three mating combinations. Peruvian females engaged in shorter copulation times than Argentinean females. Peruvian females tended to store smaller quantities of sperm than Argentinean females, and almost a half of the crosses involving Argentinean males and Peruvian females were unsuccessful (no sperm transfer). However, there was no evidence that the cross between Peruvian males and Argentinean females resulted in storage of a critically small amount of sperm (posing risk of sperm shortage). Argentinean females were more willing to remate than Peruvian females, irrespective of male morphotype, but latency to remating was not affected by male or female morphotype. This study shows that mating behaviour differs between some of the A. fraterculus complex morphotypes, with female but not male morphotype determining female likelihood to remate.

Current Sperm Competition Determines Sperm Allocation in a Tephritid Fruit Fly

“…The interpretation of the results in the case of D. melanogaster assumes that copulation duration is under male control (MacBean & Parsons ), while in our case, crosses between different morphotypes of A. fraterculus have demonstrated that copulation duration is affected by female origin but not by male origin (Abraham et al. ), suggesting that copulation duration is under female control. Female‐mediated effects could have a stronger effect on copula duration than exposure to rival males.…”

“…Alternatively, mating latency could be under female control (Abraham et al. ). Females could be detecting and copulating earlier when there are more males to choose from at the mating site, or they could be copulating earlier as a way to avoid male harassment at higher male densities.…”

Resolving cryptic species complexes of major tephritid pests

“…Sexual behaviour studies helped to identify behavioural characteristics that allowed distinct morphotype descriptions such as time of sexual activity, acoustical signals and sequence of courtship behaviour (Rull et al 2012, 2013, Devescovi et al 2014, Dias et al in press). One post-copulatory study revealed differences in sperm storage and remating propensity between the Peruvian and Brazilian 1 morphotypes (Abraham et al 2014). Hybrid females tended to mate with hybrid males and as a result Segura et al (2011) suggested that hybridization is a possible speciation mechanism.…”

Utilização diferencial de frutos hospedeiros por Anastrepha sp. 1 affinis fraterculus (Diptera, Tephritidae): aspectos morfológicos e reprodutivos

“…Essa pode ser a mesma explicação do reconhecimento e preferência em acasalar com machos provenientes do mesmo fruto hospedeiro, uma vez que o reconhecimento de parceiros e "aparentados" se dá por meio da identificação de feromônios e hidrocarbonetos de cutícula. Outro fator que pode explicar a relação do fruto hospedeiro com a escolha do parceiro pela fêmea, é que a constituição química da dieta é um dos precursores da síntese de feromônios e dos hidrocarbonetos de cutícula (Rundle et al 2005 Os trabalhos sobre compatibilidade reprodutiva no complexo A.fraterculus envolvem populações de diferentes localidades (Selivon et al 1999;Vera et al 2006;Caceres et al 2009;Rull et al 2013;Abraham et al 2014;Dias et al 2015) ou criadas em laboratório (Dias et al 2015), esse é o primeiro trabalho que estuda a compatibilidade reprodutiva associada ao uso de diferentes hospedeiros com populações encontradas em simpatria.…”