Extrafloral nectar consumption and its influence on survival and development of an omnivorous predator, larval Chrysoperla plorabunda (Neuroptera : Chrysopidae)

We examined the role of extrafloral nectar in the ecology of a larval commo n green lacewing, Chrysoperla plorabunda (Fitch). Larval lacewings were obs erved foraging freely in cotton fields and almond orchards to quantify thei r consumption of extrafloral nectar. Extrafloral nectar was a major compone nt of the diet of neonate lacewing larvae foraging on cotton. Extrafloral n ectar consumption increased strongly as the local availability of aphid pre y declined. Lacewing larvae also fed frequently on extrafloral nectar when foraging in almond orchards. A manipulative diet experiment in the field de monstrated that in the absence of arthropod prey, extrafloral nectar contri buted only slightly to neonate lacewing growth and did not support lacewing development. Nevertheless, extrafloral nectar did promote substantial long evity of first-instar lacewing larvae, which were able to maintain a high l evel of searching activity. Both the field experiment and a laboratory expe riment showed that extrafloral nectar provides nutritional benefits that ex tend beyond those provided by a simple water source. Lacewing larvae are hi ghly omnivorous: they feed on plant-based resources (extrafloral nectar), o n herbivorous arthropod prey (e.g., aphids), and on other predatory or omni vorous arthropods.