Moths Behaving like Butterflies. Evolutionary Loss of Long Range Attractant Pheromones in Castniid Moths: A Paysandisia archon Model

Background: In the course of evolution butterflies and moths developed two different reproductive behaviors. Whereas butterflies rely on visual stimuli for mate location, moths use the"female calling plus male seduction" system, in which females release long-range sex pheromones to attract conspecific males. There are few exceptions from this pattern but in all cases known female moths possess sex pheromone glands which apparently have been lost in female butterflies. In the day-flying moth family Castniidae ("butterfly-moths"), which includes some important crop pests, no pheromones have been found so far. Methodology/Principal Findings: Using a multidisciplinary approach we described the steps involved in the courtship of P. archon, showing that visual cues are the only ones used for mate location; showed that the morphology and fine structure of the antennae of this moth are strikingly similar to those of butterflies, with male sensilla apparently not suited to detect female-released long range pheromones; showed that its females lack pheromone-producing glands, and identified three compounds as putative male sex pheromone (MSP) components of P. archon, released from the proximal halves of male forewings and hindwings. Conclusions/Significance: This study provides evidence for the first time in Lepidoptera that females of a moth do not produce any pheromone to attract males, and that mate location is achieved only visually by patrolling males, which may release a pheromone at short distance, putatively a mixture of Z,E-farnesal, E,E-farnesal, and (E,Z)-2,13-octadecadienol. The outlined behavior, long thought to be unique to butterflies, is likely to be widespread in Castniidae implying a novel, unparalleled butterfly-like reproductive behavior in moths. This will also have practical implications in applied entomology since it signifies that the monitoring/control of castniid pests should not be based on the use of female-produced pheromones, as it is usually done in many moths

PHEROMONE GLAND OF THE CLEARWING, SYNANTHEDON TIPULIFORMIS CL., AND PARANTHRENE TABANIFORMIS KUNGESSANA ALPH., FEMALES (LEPIDOPTERA, SESIIDAE) © The Lithuanian Academy of Sciences

Key words. Synanthedon tipuliformis Cl., Paranthrene tabaniformis kungessana Alph., pheromone gland, morphology, histology, morphometry. Summary. It has been established by means of light-optic and electron microscopy that cells releasing pheromone in clearwing moths Synanthedon tipuliformis Cl. and Paranthrene tabaniformis kungessana Alph. females are located on the intersegmental membrane between the eighth and ninth abdominal segments. Many regular and symmetrically located mammiformlike eminences are observed on the surface of the membrane. Long, thin and curved spinelike processes are distributed on the top of eminencies. The glandular cells are cylindrical with large nuclei. The height of the cells of a Synanthedon tipuliformis Cl. is 21-31 µ and their width is 8-12 µ, the diameter of the nuclei is 5.6-7 µ. The height of such cells in a Paranthrene tabaniformis kungessana Alph. accounts for 17.5-22 µ and their width is 8-13 µ, the nuclei diameter is 7.5-12.5 µ