Parasitization by the microhymenopteran Gryon triatomae Masner of eggs of Triatoma maculata (Erichson) in holes and mazes of artificial walls.
Oriental parasitoid wasps, Gryon triatomae, were confined for several weeks in transparent tanks (400 X 180 X 200 mm) with eggs of the neotropical triatomine bug Triatoma maculata. The eggs were lodged in moulded holes (about 50 mm deep and 15 mm diameter) of polystyrene blocks, to simulate walls. The blocks were arranged with the holes either vertical or horizontal; openings of the holes were either 5 mm or 15 mm diameter. One wall included three mazes of linked holes, each maze with one entrance. Eggs were also accessible in an open petri-dish and on top of one wall. Some eggs in the walls and the maze block were in holes sealed off from access by wasps to provide controls, in order to assess fertility of the eggs, since this favours parasitization. This was satisfactory at 82.2% and 88.5% in two tanks studied. Parasitization rates were 32% of 50 eggs exposed to one female G. triatomae, with one male wasp, in one tank, and in the other 55.9% of 136 eggs exposed to 14 female wasps, with five males. In both tanks, eggs in the open petri-dish, in accessible vertical and horizontal holes and on top of walls were parasitized, but parasitization of eggs in the mazes occurred only in the tank with 14 female Gryon and then as far as the last, 18th, hole of the longest maze, a linear penetration by a searching wasp of about 270 mm; the distance travelled could be considerably greater. Late wasp oviposition after protracted questing may have caused the observed 15.8% abortion rate of G. triatomae. The few wasps seen by night were at rest, but at daybreak many more emerged from the walls and flew actively.(ABSTRACT TRUNCATED AT 250 WORDS)
D000818:Animals; D001522:Behavior, Animal; D002940:Circadian Rhythm; D005260:Female; D005426:Flight, Animal; D006927:Hymenoptera / Q000502:physiology*; D008297:Male; D010063:Ovum / Q000469:parasitology; D012098:Reproduction; D014224:Triatoma / Q000469:parasitology*; D014225:Triatominae / Q000469:parasitology*; D014863:Wasps / Q000502:physiology*