Kontodimas, D.C., Lykouressis, D., Karandinos, M.G., Katsoyannos, P.I., Stathas, G.J., Eliopoulos, P.A., & Economou, L.P. 2005 The effect of temperature on the development of Nephus includens and Nephus bisignatus, predators of Planococcus citri. (Abstract only).. Proceedings of the X International Symposium on Scale Insect Studies, held at Plant Protection Research Institute, Adana/ Turkey, 19-23 April 2004. Adana Zirai Muscadele Arastirma Enstitusu. Adana, Turkey 408 pp.

Notes: The effect of temperature on the development of the predators Nephus includens (Kirsch) and Nephus bisignatus (Boheman) (Coleoptera: Coccinellidae), was studied. The development time of immature stages and the pre-oviposition period of adult females for the two predators was recorded at eight constant temperatures (10, 15,20,25, 30, 32.5, 35 and 37.5°C). The beetles were reared on eggs, nymphs and female adults of Plano coccus citri (Risso) (Homoptera: Pseudococcidae) that had developed on squash (Cucurbita pepo) and on sour orange leaves (Citrus aurantium). Using the linear model for the biological cycle of N. includens on squash and on sour orange, the developmental zeros (lower temperature thresholds) were estimated to be 10.9 and 11.0°C respectively and the thermal constants, 490.5 and 472.8 day-degrees respectively. Using the Lactin model the lower thresholds were estimated be 11.1 and Il.2°C respectively and the upper thresholds 36.1 and 36.0°C respectively. For the biological cycle of N. bisignatus, using the linear model, the lower thresholds were estimated to be 9.4°C on squash and 9.3°C on sour orange and the thermal constants were 614.3 and 647.9 day-degrees respectively. Using the Lactin model the lower thresholds were estimated be 9.9 and 10.00C respectively and the upper thresholds, 34.7 and 35.0°C respectively. The survival rate of N. includens instars at 10, 15, 20, 25, 30, 32.5, 35 and 37SC on squash and on sour orange was, respectively, 0.0, 34. 9-32.2, 63.2-61.0, 70.6-68.0, 63.3-68.3, 54.5-56.6, 19.8-17.6 and 0.0%. The survival rate of N. bisignatus instars at 10, 15,20, 25, 30, 32.5 and 35°C on squash and on sour orange was, respectively, 0.0, 39.9-35.7, 61.1-65.7, 60.7-68.0, 47.2-44.2, 26.4-29.1 and 0.0%. The results show that N. includens has a shorter biological cycle than N. bisignatus whereas the latter species is more tolerant of lower temperatures.