0000000000205069
AUTHOR
Carlos Cordero
Males of the tortricid moth Amorbia cuneana (Walsingham, 1879) shed their genital spines inside the female during copulation
Abstract The genitalia of most insect species are composed of several structures whose functions are poorly understood in many cases. The deciduous genital spines (deciduous cornuti, DC) found on the endophallus of many species of Lepidoptera are a clear example of this problem. We performed two experimental studies with the western avocado leafroller Amorbia cuneana (Tortricidae), aimed at answering some basic questions about the biology of DC. We found that the number of DC shows positive allometry with male forewing length, indicating that larger males have disproportionally more DC than smaller males. Males, with very few exceptions, shed virtually all their DC in their first copulation…
Atypical functioning of female genitalia explains monandry in a butterfly
Monandrous species are rare in nature, especially in animals where males transfer nutrients to females in the ejaculate. The proximate mechanisms responsible for monandry are poorly studied. In butterflies and moths, the male transfers a nutritious spermatophore into the corpus bursae (CB) of the female. The CB is a multifunctional organ that digests the spermatophore and has partial control of the post-mating sexual receptivity of the female. The spermatophore distends the CB and the post-mating sexual receptivity of the female is inversely proportional to the degree of distension. The CB of many butterfly species has a muscular sheath whose contractions mechanically contribute to digest t…
Sexual Selection Within the Female Genitalia in Lepidoptera
The genitalia of male and female Lepidoptera are complex organs, composed of several structures that exhibit great diversity of shapes, sizes, and positions, suggesting that they have evolved in a relatively rapid and divergent way. In this chapter, we explore the selective pressures responsible for the evolution of genital morphology in the Lepidoptera , emphasizing the possible role of post-copulatory intersexual selection (PCIS) mechanisms (cryptic female choice and sexual conflict). Our exploration is in great extent speculative because knowledge on the functional morphology of genitalia in this group is limited. We start by describing the complexity and diversity of genitalia in Lepido…