Superparasitized host

Levels of JH III in suspense superparasitized by B. longicaudatus were considerably higher than in unparasitized A. suspense (53) JH III was also found in first instars of the parasitoid. These results suggested that the elevated JH III levels in the superparasitized host may result from a decrease in JH esterase activity with a continued or elevated synthesis of the hormone in the host or from a secretion of JH III by the parasitoids. 

Parasitoid marking pheromones, according to van Lenteren (1981) (i) prevent multiple ovipositions into the same host and consequent egg wastage, (ii) prevent host wastage because superparasitized hosts often die, resulting in death of the parasitoids, (iii) save time, particularly if the process of attack and oviposition are lengthy and (iv) initiate migration to more productive habitats when several marked hosts are encountered. 

Unlike parasitoids of other insect orders that have host-seeking larvae, most parasitic hymenoptera lay their eggs on, in, or very close to a host individual [11]. This requires the adult female to find a suitable host, often with the aid of chemical cues from host frass, pheromones, plant volatiles emitted upon host feeding or egg-deposition, silk, honeydew and other secretions. She may then chemically mark the host following oviposition to reduce superparasitism by herself or intra- and inter-specific insects [11]. 

Other types of virus material have been recorded from parasitic hymenopteran species. Viral particles of parasitoid origin were reported in tissues of the suspense superparasitized by the solitary endoparasitoid B. longicaudatus (112). Rhabdoviruses were found in vesicles near the basement membrane of the host epidermal cells and pox viruses were found in hemocytes adjacent to the epidermis (Lawrence, P. 0. Akin, D. Canad. J. Zool., in press). 

The ability to discriminate also appears to be influenced by experience (van Lenteren, 1976). As shown by van Lenteren (1976), inexperienced females may superparasitize many hosts until they encounter unparasitized hosts and learn to discriminate. It also appears that location of the host may be a matter of experience. Female Cardiochiles nigriceps are more likely to search for and attack hosts if they have previously encountered a host than inexperienced females (Strand and Vinson, 1982a). 

Bragg, D. (1974) Ecological and behavioral studies of Phaeogenes cynarae Ecology host specificity search and oviposition and avoidance of superparasitism. Ann. ent. Soc. Am., 67, 931-36. 

Van Lenteren, J. C. (1976) The development of host discrimination and the prevention of superparasitism in the parasite Pseudeucoila biochei (Hym., Cynipidae). Neth. J. ZooL, 26, 1-83. 

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