Lepidoptera genitalia

About: Lepidoptera genitalia is a research topic. Over the lifetime, 10114 publications have been published within this topic receiving 78876 citations. The topic is also known as: Uncus.

Characterization, distribution, biology and impact on Italian walnut orchards of the invasive North-American leafminer Coptodisca lucifluella (Lepidoptera: Heliozelidae).

Abstract: The leafminer Coptodisca sp. (Lepidoptera: Heliozelidae), recently recorded for the first time in Europe on Italian black and common walnut trees, is shown to be the North-American Coptodisca lucifluella (Clemens) based on morphological (forewing pattern) and molecular (cytochrome oxidase c subunit I sequence) evidence. The phylogenetic relatedness of three species feeding on Juglandaceae suggests that C. lucifluella has likely shifted, within the same host plant family, from its original North-American hosts Carya spp. to Juglans spp. Over the few years since its detection, it has established in many regions in Italy and has become a widespread and dominant invasive species. The leafminer completes three to four generations per year, with the first adults emerging in April–May and mature larvae of the last generation starting hibernation in September–October. Although a high larval mortality was recorded in field observations (up to 74%), the impact of the pest was substantial with all leaves infested at the end of the last generation in all 3 years tested. The distribution of the leafminer in the canopy was homogeneous. The species is redescribed and illustrated, a lectotype is designated and a new synonymy is established.

Sensory Efficacy of Alkyl-Branched Pheromone Analogues in Noctuid and Tortricid Lepidoptera

Abstract: Abstract The effect of introducing alkyl substituents (methyl to pentyl) to the chain segment n in long-chain alkenyl acetates, CH3(CH2)nCH = CH(CH2)m-O-COCH3 (I), was investigated in pheromone receptors of Noctuidae, Tortricidae, and Cochylidae species. The receptor types studied were maximally responsive to (Z)-7-or (Z)-9-dodecen-1-yl acetate, (Z)-7-, (Z)-9-, or (Z)-11-tetradecen-1-yl acetate, or (Z)-11-hexadecen-1-yl acetate, representing key compounds with n = 1, n = 3, or n = 5 methylene groups. In terms of the relative stimulus amounts required to elicit equivalent EAG amplitudes, the efficacy of the alkyl-branched derivatives was between 1/1000 to 300 times that of the unbranched chain of the same length and double bond position. The effects of branching were specific to the type of receptor, the length and double bond position of the parent chain, and the kind and position of the alkyl substituent. The most pronounced increase observed occurred with receptors for « = 1 type pheromones, (Z)-9-dodecen-1-yl acetate and (Z) -11-tetradecen-1-yl acetate when an α-methyl group was introduced to elongated derivatives; whereas the greatest decreasing effects were obtained on receptors for the n = 5 type compound, (Z)-7-tetradecen-1-yl acetate. The results show basic differences in structure-response relationships between the Noctuidae vs Tortricidae receptors studied. Various possible effects of the substituent groups during sensory transduction are considered. The data should contribute to further elucidation of interaction mechanisms of unbranched alkenyl acetate pheromones (I) with insect olfactory receptors.

Effects of Constant and Alternating Temperatures on the Development of Spodoptera litura F. : Lepidoptera : Noctuidae

Abstract: peratures for the development ofthe egg, larva, prepupa, and pppa were estimated to be 10.1O, 10.6\", 12.0a, and 9,OO C, respective]y. The threshold temperature and the thermal constant for development from the egg to the adult form were also cstimated to be 10,30C and 526.3 day-degrees. It was censidered that thc development of the laTvae and the pupae tended to be acceicrated under alternating temperatures as comparecl with that under constant temperatures,