Parasitoid complex of the mealybug Oracella acuta (Lobdell) (Hemiptera: Pseudococcidae), in Georgia, USA

Abstract

The parasitoid complex of the mealybug Oracella acuta (Lobdell) was examined in two field populations in Georgia in 1995-96. Allotropa n. sp. and Zarhopalus debarri Sun were the primary endoparasitoids emerging from O. acuta. Adult abundance varied seasonally, with Allotropa n. sp. numbers peaking in June and Z. debarri in September. Parasitism rates of female O. acuta exceeded 60% at one site and ranged from 24 to 29% at the other site. The adult female was the preferred host stage for parasitism (76%), though Allotropa n. sp. and the endoparasitoid Acerophagus coccois E. Smith occasionally utilized second and third instar females as hosts. These two species exhibited gregarious parasitism, with up to 5 Allotropa n. sp. or 4 A. coccois emerging from a single host. Adult longevity of female and male Z. debarri averaged 6.4 and 5.3 days, respectively, and access to a food source usually increased adult lifespan. Female Z. debarri contained an average of 119 eggs, compared to 74 eggs per female for Allotropa n. sp.