TEMPERATURE-DEPENDENT DEVELOPMENT IN A POLYMORPHIC LADY BEETLE, CALVIA-QUATUORDECIMGUTTATA (COLEOPTERA, COCCINELLIDAE)

The influence of temperature on the development rate and expression of 3 elytral color patterns in the lady beetle, Calvia quatuordecimguttata (L.), was assessed at 6 constant temperatures between 10 and 34 degrees C. The expression of the 3 elytral color patterns was discrete and independent of temperature treatment. No differences were observed among the color morphs in the real or physiological time for egg-to-adult development, or for pupal weight. However, temperature did influence survival and growth rates of the overall population. No eggs hatched at 34 degrees C. Larval mortality was high at 10 degrees C and moderate between 14 and 30 degrees C. Development time from oviposition to adult was 14.6 +/- 0.9 d at 30 degrees C and 95.6 +/- 9.0 d at 10 degrees C. The total heat-unit requirement for egg to adult development was 274.1 DD above a mean development-threshold of 8.2 degrees C. Pupal weight differed among temperature treatments and was greatest at 10-22 degrees C, and lowest at 26 and 30 degrees C.