Moths of the Amazon
Möschler's Wasp Mimic
© Adrian Hoskins
There are about 6000 known species of Arctiinae in the neotropical
region. Most are noxious to birds and have aposematic or diematic
warning coloration. The tribe Ctenuchini is entirely confined to the
Americas. It is comprised of 2 subtribes Ctenuchina and Euchromiina
which together account for a total of 2532 known species, of which
2496 are wholly neotropical in distribution. The remaining 36
species are partly or wholly North American in distribution. Almost
all of the genera within these two subtribes consist entirely of
species that mimic wasps or bees.
There are 187 known species in
the genus Cosmosoma. The moths are
restricted to the neotropics and southern limits of the nearctic,
with the greatest diversity and abundance in the rainforests and
cloudforests of Brazil, Ecuador and Peru.
is a cloudforest species found at elevations between about 500-1800m.
To be completed.
As is generally the
case with nocturnal
moths, males of
are attracted by pheromones emitted by the females. As the male
approaches a female he hovers above her and discharges a burst of
very fine filaments which swirl in the air around her, and envelop
Conner and Boada found that Cosmosoma
males are attracted to Eupatorium
plants, and sequestered alkaloids from juices seeping from the
stems. Such pyrrolizidine alkaloids are sequestered by a wide
variety of butterfly genera including Ithomia,
Lycorea and Danaus; and by
several genera of moths in the family Arctiidae. The PAs stored in
the bodies of the insects render them toxic or unpalatable to birds,
and are a primary defence method in aposematic species.
found that in the case of Cosmosoma the
toxins seemed to be directed mainly at predatory spiders. Moths
caught in the webs of Nephila clavipes
were cut free from the webs by the spider, but moths which had been
deprived of the opportunity to sequester PAs were consumed.
Conner and Boada
found that PAs were passed to females via the discharged filaments,
and also via spermatophores delivered during copulation. The toxins
conveyed to females were found to provide them with protection
against predators during the following nights, enabling them to lay
their eggs unmolested. It was also demonstrated that the toxins were
passed to the eggs, and provided them with protection against ants,
Coccinellid beetles ( ladybirds ) and Chrysopid larvae.
Villa Rica, Peru
© Adrian Hoskins