Butterflies of the
Amazon and Andes
Family - NYMPHALIDAE
subfamily - DANAINAE
Tribe - ITHOMIINI
male at bird dropping, Rio Madre de Dios, Peru ©
The Ithomiini comprises of 376 known species,
although it is likely that at least another 30 will be discovered in
the near future. All are confined to the neotropical region.
are unpalatable to birds, and are consequently mimicked in
appearance by many other species. These include other unpalatable
species ( Müllerian mimics ), not only from the Ithomiini but also
from several other butterfly families. There are also a large number
of edible species ( Batesian mimics ) which have evolved similar
patterns. Birds have the ability to memorise butterfly patterns and
so learn to avoid eating noxious species, but are also fooled into
ignoring similarly marked edible species.
characterised by having small eyes, slender abdomens and long
drooping antennae that lack distinct clubs. Males have a plume of
long androconial scales or "hair pencils" on the costa of their
hindwings. These are hidden from view when the butterflies are at
rest, but are displayed when the wings are held open during
courtship. Other Ithomiine characteristics include a very slow and
deep wing beat, and a preference for inhabiting the darkest recesses
of the forest understorey.
are basically 2 types of Ithomiine. The first type are the black and
orange-banded "tigers", many of which are mimicked by other species
due to their unpalatability to birds. The second type are the
"glasswings", recognised by their transparent or translucent wings,
prominent veins, and orange wing margins. Many genera contain
examples of both of these types, and in some cases an individual
species may produce adults of both forms according to location.
novices find the Ithomiini very difficult to identify. Using only
the patterns to identify species is very unreliable because there
are so many similar species. Also many species produce a variety of
different colour forms according to locality and season. The best
approach therefore is to use the hindwing venation and other
anatomical features to identify the genus, and to then look at the
wing patterns to short-list the likely species.
Napeogenes contains 22 known species of
small to medium sized Ithomiines, some falling into the "Glasswing"
category while others have the black, orange and yellow makings
typical of the "Tiger" mimicry complex. There are 6 genera -
Rhodussa and Hypothyris.
There is some contention between taxonomists as to whether this
species should be classified under the genus
Hypothyris or Rhodussa. It has
also at various stages of history been classified under
Ithomia. Lamas ( 2004 ) includes this and 17 other species in
Hypothyris, and regards
Rhodussa as a junior synonym. Brabant
however points out ( pers comm ) that there are minor differences in
the venation of Hypothyris and
Rhodussa, and places
cantobrica in the latter genus.
This species is found in the upper Amazon regions
of Brazil, Peru and Bolivia.
The butterfly occurs in lowland rainforest at altitudes between
about 100-900 metres.
To be completed.
The butterflies are usually observed as singletons, seen at rest on
foliage in light gaps where trees have fallen in the forest. This
probably implies that they spend much of their time in the middle or
upper canopy, only descending at places where the sunlight penetrates
to lower levels.
other Ithomiines, the butterflies spend long periods at rest on the
foliage of small shrubs in the darkness of their rainforest and
cloudforest habitats. They are extremely nervous, and if disturbed fly
immediately, only to resettle on another nearby leaf. The flight is
very slow, with characteristic deep wing beats. When feeding in the
open they behave very differently - both sexes being very placid and
reluctant to leave their flowers.
sequester pyrrolizidine alkaloids from
Myosotis ( Boraginaceae ),
Neomiranda and Senecio (
Asteraceae ). These chemicals confer toxic qualities to the
butterflies which deter bird attacks. The chemicals are also used in
the production of pheromones. Often the males of several Ithomiine
species will gather together at communal leks, where they release
these pheromones from hair-like androconial scales on the leading edge
of their upperside hindwings. These attract more males, which in turn
release further pheromones. After a few days the lek may include 50 or
more adults comprised of as many as dozen different species. Passing
females are attracted to the leks by the complex fragrances. Their
presence stimulates the males to open their wings and release further
pheromones that entice them into copulation. Females obtain sustenance
from nectar, and also visit bird droppings which provide them with a
source of nitrogen that assists with the development of their eggs.