Perching Mate-Locating Strategy in <I>Paysandisia archon</I> (Lepidoptera: Castniidae): Behavioral and Morpho-Physiological Investigations

Abstract

We studied Paysandisia archon (Burmeister) (Lepidoptera: Castniidae: Castniinae) courtship behavior to provide a detailed qualitative and quantitative description of male and female behaviors. Moreover, to investigate the role of antennal olfaction and visual stimuli in mate-recognition, bioassays with antennectomized adults and dummies were performed. To assess the presence of a pheromone gland in the ovipositor, morphological (using light and scanning electron microscopic techniques), electrophysiological, and chemical investigations were carried out. We observed perching mate-locating behavior of P. archon males, with the female triggering the courtship sequence by approaching the perching male first. The stereotyped courtship sequence is made up of five main steps: female flight, pair flight, alighting close, copulation attempt, and clasping. Our findings suggest that visual cues are important in P. archon courtship behavior, and the role of chemical cues is also discussed. Moreover, we observed a higher antenna cleaning frequency in females than in males. Ovipositor extrusions during courtship appeared not to be related to calling behavior, and histological investigations showed no evidence of glandular tissues involved in sex pheromone production. The P. archon ovipositor consists of the eighth uromere, which forms the ovipositor base, and the 9th and 10th uromeres are fused together and connected to the base by an intersegmental membrane. Overall, 24 compounds were identified from extracts obtained from ovipositors: 9 compounds were detected only in extracts from the ovipositors of 24-h-old virgin females, and not from those of 1-h-old females. None of these compounds elicited any significant electrophysiological responses from male antennae.

Paysandisia archon: Behavior, Ecology, and Communication

“…A likely perching mate-locating behavior is performed by males; females trigger the courtship sequence by approaching perching males, which then pursue the females (Delle-Vedove et al 2014;Riolo et al 2014). Female courtship solicitation has also been observed in Pieridae (Rutowski 1980;Daniels 2007) and Nymphalidae (Bergman et al 2007) species.…”

“…Detailed qualitative and quantitative descriptions of P. archon male and female reproductive behavior have been reported in two recent studies showing that the courtship is a sequence of stereotyped behavioral steps (Delle-Vedove et al 2014;Riolo et al 2014). A likely perching mate-locating behavior is performed by males; females trigger the courtship sequence by approaching perching males, which then pursue the females (Delle-Vedove et al 2014;Riolo et al 2014).…”

“…All of these steps are necessary for copulation to occur (Table 7.1; Fig. 7.1) (Riolo et al 2014). Multiple repetitions of courtship steps are engaged by both males and females.…”

“…The average courtship duration was 60.99 ± 18.97 min (mean ± SE), and the longest copulation lasted 94.58 min. On average, adults mated from 0 ± 2 days of age (Riolo et al 2014). Despite the stereotypy of the behavioral sequence, P. archon courtship is variable and complex, especially in terms of the number of components and event transitions, which also involve other optional male and female behaviors (Riolo et al 2014).…”

Paysandisia archon: Taxonomy, Distribution, Biology, and Life Cycle

“…In outdoor experiments, mating peaks between 1400 h and 1500 h, and 87% of the females are fertilized and start laying eggs 1.25 (±1.14) days after mating (Delle Vedove et al 2012). Riolo et al (2014) reported that in semi field conditions mating occurred mainly in the morning from 0930 to 1130 h; mated moths were 1-2 days old. Under laboratory conditions, mating occurred in the afternoon, as soon as the cage with males and females was in the sun (Beaudoin-Ollivier, unpublished).…”