Insects and beetles frequenting cycads

It is always difficult to see cycad beetles on these plants, because their appearance period on the cones and also on the fronds is very short, and it sometimes happens during the night or at dusk (Windsor et al. 1999). PJ observed them on the fronds in Panama paying a very short visit. The insects come to the plants one week after the strong spring rains, in May normally, and their visits stop totally one month later. They seem to survive as diapausing egg and larval stages hidden somewhere. The appearance of the insects on the male cones is linked with the latter's maturity and can be autumnal, as in Florida. Some Aulacoscelinae (Chrysomelidae) appear on leaves in spring in Central America and in December in Bolivia.

As mentioned by Crowson (1989), the beetles frequenting cycads are found mostly on the male cones and on the leaves, and rarely on the trunks (only some weevils). A few have been observed on female cones, where they help fertilization, often in the evening. None has yet been found on the roots, but that is probably due to lack of careful search. Some larvae are certainly adapted to radicolous life and probably the larvae of aulacoscelines are seed borers, as those of the bruchids, but these probabilities remain to be confirmed.

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