A standardized laboratory procedure tested the limb regeneration abilities of 18 populations (16 species) of lady beetles which were then scored, relative to unoperated controls, based on survival, the proportion regenerating the limb completely or partially, and the magnitude of developmental costs (delayed development, reduced body size) associated with limb ablation. Newly molted fourth instar larvae each had a single foreleg amputated at the base of the femur. All species except Propylea dissecta (Mulsant) showed some complete limb regeneration, with limb regeneration index (LRI) scores ranging from 0.025 to 0.905 out of a possible 1.00 (mean = 0.598). Eriopis connexa Germar, an aphidophagous neotropical species, scored the highest. Widely distributed species that dominate agricultural habitats all scored above 0.75, and the only herbivore, Henosepilachna argus (Geoffroy), scored second from lowest. Prolonged pupal development was the most common cost, occurring in nine species, and correlating negatively with regeneration. Taxonomic distance between species correlated with regeneration, but explained <5% of variation; principal component analysis indicated that the LRI was the main factor distinguishing species. We infer that this capacity is conserved, not because of any adaptive advantage conferred, but because the genes responsible are normally activated during pupal development to generate the adult body plan and reconstitute appendages with direct correspondence to larval progenitors. However, good regeneration capacity was associated with the ecological success of the species. In general, broad geographic distribution, guild dominance, polyphagy, interspecific competitiveness, phenotypic flexibility, and invasiveness were characteristics generally shared by species with high levels of regeneration.

http://www.eje.cz search, pet food and to rescue endangered species (Leopold, 2007). However, the infl uence of cold storage on the effi cacy of predators is poorly investigated. Following cold storage, increase in mortality decreases the effectivity of biocontrol insects. Less apparent are the sublethal effects of storage. Lady beetles in the temperate climatic zone overwinter as adults and those of Coccinella undecimpunctata survive better than the other developmental stages (Abdel-Salam & Abdel-Baky, 2000). Storage of second and third instar larvae of Coleomegilla maculata for two weeks at 4 and 8°C results in almost 100% survival (Gagné & Coderre, 2001). More than 80% of Harmonia axyridis adults survive 150 days at 3°C and 6°C (Ruan et al., 2012). Sublethal effects of prolonged storage include delayed oviposition, lower fecundity and fertility and lower voraci

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Ladybeetles are known beneficial insects, with a long history in augmentative and classical biological control. The ladybeetle Oenopia conglobata (L.) is a natural enemy of many herbivores, particularly aphids. The temperature-dependent development of O. conglobata was studied at six constant temperatures (22.5, 25, 27.5, 30, 32.5 and 35 °C) to understand its development rate and environmental constraints better. Linear and nonlinear (Lactin) models were fitted to the data. In the thermal range from 22.5 to 32.5 °C, the rate of development increased for all stages; 35 °C was lethal for all stages and no eggs hatched. The Tb and K values for the biological cycle (egg–adult) were 8.84 °C and 263.15 DD, respectively. Depending on the model, tmin values for the total development time of the coccinellid ranged from 8.45 to 8.82 °C. The nonlinear model of Lactin estimated the optimum and upper temperature thresholds for the total development time of the ladybeetle to be 33.2 and 35.0 °C, respectively. High R2 values and low residual sum of squares values revealed a good fit to the experimental data for total development and different developmental stages of O. conglobata. The results may contribute to the improvement of practical methods for mass rearing of O. conglobata.

Ladybirds (Coleoptera: Coccinellidae) use toxic compounds such as alkaloids in their hemolymph to defend against predators and pathogens. Direct measurement of their toxicity to predators is unavailable as predators show various avoidance reactions without eating the beetles. Because inhibition by harmonine – the alkaloid of the alien invasive ladybird Harmonia axyridis (Pallas) – was observed in many organisms, its toxicity can also be tested on various non‐target organisms. This is the first study examining ladybird alkaloid toxicity to plants. We used a quick, inexpensive, and easy‐to‐perform method to quantify the phytotoxicity of 13 strains of H. axyridis, representing natural colour forms and spontaneous laboratory mutations. We used the seed germination rate and root elongation of seedlings of Sinapis alba L. (Brassicaceae). Following a logistic curve, root length decreased with increasing concentration of the extract from adult beetles. The effect of extracts from the cowpea weevil, Callosobruchus maculatus (Fabricius) (Coleoptera: Chrysomelidae) (negative control) did not differ from the control (water). Extract from the lesser mealworm Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae) (positive control) decreased the root length to about half of that of the negative control. Extract from young ladybirds (1 week old) decreased the root length to about one‐third of the control and the extract from 3‐month‐old ladybirds to one‐10th. Differences in toxicity among all 13 strains were minor and not consistent for the two age cohorts.