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patterns on the wing tips. Megaloprepus contains only one species, M. coerulatus (fig. 6.3c), which has a greater wingspan (60-75 mm) than most species of Mecistogaster (usually 60—65 mm, but up to 170 mm) but a shorter abdomen (76—96 mm compared to up to 135 mm). The wings of Megaloprepus are marked subapically with a broad, dark purple band and are suffused basally with white (in the males), while in Mecistogaster, orange, yellow, or red color fields are present near the wing tips (fig. 6.3d). Wing coloration sometimes varies within a species due to age or seasonal differences. Mecistogaster often has no light-colored spot, but all the members of the family are characterized, without exception, by a multicelled pterostigma. Size has been found to vary greatly in the adults owing to differences in the quality of the nymphal habitats (Fincke 1984).

The nymphs are among the few Zygop-tera that employ bromeliad tanks and tree holes for development. Young (1981) has observed Megaloprepus ovipositing in an accumulation of water in a depression in the trunk of a fallen tree. Female Mecistogaster are known to throw their eggs singly onto the water surface in such container habitats. The very long, slender abdomen appears to be an adaptation to facilitate this procedure (Machado and Martinez 1982).

For food, the adults specialize on kleptoparasitic spiders that live in the webs of orb weavers (Araneidae such as Nephila and Gasteracantha) (Young 1980). In flight, they approach the web and flutter before it briefly prior to darting in to pluck out the prey, which they carry to a nearby perch to devour.

Males of the sexually dimorphic Megaloprepus hold mating territories around water-filled tree holes for up to two months, defending them from conspecific males and permitting only females with whom they have mated to enter and oviposit in the holes (Fincke 1984).

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