Mating patterns in the aphidophagous ladybird, Hippodamia variegata, depend on body size

Abstract

Body size dependent mating patterns were investigated in an aphidophagous ladybird, Hippodamia variegata (Goeze), which was reared on mustard aphid, Lipaphis erysimi (Kalt.). Both males and females of varying body sizes were used to test the hypothesis that bigger is better. The costs of copulation on the life history traits of the mating partners were determined. Pairs of virgin beetles were allowed to mate once under controlled conditions and the duration of copulation of heavy beetles (504.00 ± 45.93 min) lasted significantly longer for than that of light beetles (270.00 ± 26.67 min). Body size was significantly positively correlated with duration of oviposition, fecundity and egg viability. When light individuals mated with heavy partners, copulation lasted longer between heavy males and light females (483.00 ± 54.73 min) than between light males and heavy females (378.20 ± 83.03 min). These results support the hypothesis that males determine the duration of copulation and that the reproductive success of large males is greater than that of small males. The longevity of heavy males was significantly shorter (37.40 ± 1.50 days) than that of light males (53.10 ± 2.84 days). This difference in the longevity of beetles of different sizes could contribute to the significant variation body size in H. variegata recorded both in the field and stock cultures, where light males outnumber heavy ones. Thus, although large males have a reproductive advantage over small males, other factors, such as reduced longevity, may constrain the evolution of even larger males.

Antennal morphology and sensilla of the predaceous ladybirds, Menochilus sexmaculatus and Propylea dissecta

“…Majority of predaceous ladybirds (Coleoptera: Coccinellidae) can be utilized for the biological control of numerous phytophagous insect-pests: aphids, scale-insects, mealybugs and whiteflies (Hodek et al 2012;Omkar and Pervez 2016) infesting several economically important crops (Pervez et al 2020). The optimization of their predation potential (Pervez and Yadav 2018;, prey consumption (Pervez and Kumar 2017) and mating behaviour (Pervez and Singh 2013) may enhance the biocontrol potential of ladybirds.…”

Polimorfismo y dimorfismo sexual de Hippodamia variegata (Goeze) (Coleoptera: Coccinellidae) en la Región Arequipa, Perú

“…Muchas especies de coccinélidos presentan dimorfismo sexual (Pervez y Singh 2013). El tamaño corporal de un coccinélido adulto es probablemente el resultado de una interacción compleja del genotipo con las condiciones ambientales experimentadas por el depredador inmaduro en desarrollo (Evans 2000).…”

“…Cuando el alimento es escaso los machos pequeños se aparean con más éxito que los machos grandes (Yasuda y Dixon 2002). Por otro lado en las hembras, un mayor tamaño garantiza una mayor cantidad de recursos y una mayor fecundidad (Pervez y Singh 2013). Poblaciones de H. variegata estudiadas en Irán criadas en condiciones de laboratorio y en campo mostraron que en ambas situaciones las hembras fueron de mayor tamaño que los machos (Abdolahi et al 2016).…”

Mating behaviour of the predaceous ladybird, Harmonia dimidiata

“…Mating in ladybirds starts with a brief courtship by the male (Omkar and Pervez 2005). Behavioural studies on mating reveal that males spend most of their time searching for potential mates and on encountering a female they court her before copulating (Obata 1987;Omkar and Srivastava 2002;Omkar 2004;Pervez and Singh 2013).…”