Female sexual maturity as a determining factor of size-assortative pairing in the protandrous spider Manogea porracea (Araneae, Araneidae)

Protandry occurs when males mature prior to females in the breeding season. There may be a fitness benefit for males if they are able to copulate and defend virgin and more fecund females. Therefore, fitness benefits can be investigated by studying assortative mating during mate guarding of virgin females before and after female sexual maturation. The asynchrony of female development in the protandrous spider Manogea porracea (Araneidae) provides an opportunity to investigate how female sexual maturity (subadult and adult females) influence size-assortative pairing. We investigated size differences between couples composed of males and subadult females, and of males and adult females. We hypothesized that size-assortative pairing is stronger in couples with adult females. Adult females were larger than subadults, but the size of males paired with females from both groups was similar. We found assortative pairing within all couples involving an adult female. However, this pattern was not observed among couples with subadult females. It is possible that the production of sexual pheromones by adult females after their last molt intensifies male intrasexual competition, promoting positive assortative pairing. We discuss the potential mechanisms affecting male mate choice and mate competition during pairings in M. porracea28416CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAIS - FAPEMIGFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP306157/2014-4; 403733/2012-0; 445832/2014-2; 465562/2014-0; 441225/2016-0sem informaçãoAPQ-02984-17; APQ-02104-14; CRA-30058/12; APQ-03202-13; APQ-02474-15465562/2014-0; 2017/14196-5We thank Giancarlo MSc. Ângelo Ferreira and Yuri Lima Vasconcelos Ferreira for providing transport to the study area in several occasions. We also thank Dr. Gustavo Requena for his important contributions to the first drafts. This project was supported by Fundação de Amparo à Pesquisa do Estado de São Paulo (São Paulo Research Foundation, FAPESP: Proc. 465562/2014-0; 2017/14196-5), Duratex S.A., Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Instituto Nacional de Ciência e Tecnologia dos Hymenoptera Parasitoides da Região Sudeste (HYMPAR/Sudeste – CNPq/CAPES/FAPESP), Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG: Proc. APQ-02984-17, APQ-02104-14, CRA-30058/12, APQ-03202-13; APQ-02474-15), and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq: Proc. 306157/2014-4; 403733/2012-0; 445832/2014-2; 465562/2014-0; 441225/2016-0