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Butterflies of
the Amazon and Andes
Tiger Mimic Longwing
Heliconius numata
CRAMER, 1780
Family -
NYMPHALIDAE
subfamily -
HELICONIINAE
Tribe - HELICONIINI
introduction
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habitats |
lifecycle |
adult behaviour
Heliconius
numata, Rio Madre de Dios, 500m, Peru
Introduction
The Heliconiinae is
subdivided into the tribes Acraeini,
Argynnini,
and Heliconiini.
The
Heliconiini are colloquially known as Longwings, and are confined exclusively to
the neotropical region. All species have elongated wings with a dark brown or
blackish ground colour. Most of the 39 species in the genus
Heliconius
are marked with patches or streaks of bright orange, red and / or cream. A few,
such as
sara,
antiochus
and
wallacei have a metallic blue sheen over the basal area of both wings. All are
characterised by their delicate fluttering flight, long straight antennae, and
fondness for flowers.
Heliconius numata is
a member of what is commonly called the "tiger complex" - a group of about 200
species from various families which all share a common pattern of orange stripes
on a blackish ground colour.
Most of these species are
Müllerian mimics -
toxic species which benefit by sharing a common pattern, because any bird which
suffers the unpleasant experience of tasting one member of the complex quickly
learns to avoid attacking any similar looking species. Even skilled
entomologists often have difficulty distinguishing the many unrelated species in
this group.
As well as Müllerian mimics such as
the Ithomiines
Tithorea harmonia and
Melinaea marsaeus, and toxic Danaines
such as
Lycorea pasinuntia,
the tiger-complex also includes lower numbers of non-toxic
Batesian mimics.
Among these are
Heliconius numata,
Heliconius hecale,
and many members of other families such as
Perrhybris pamela ( Pierinae ),
Pterourus zagreus ( Papilioninae ), Eresia eunice ( Nymphalinae ), Consul fabius
( Charaxinae ), and even a Riodinid -
Stalachtis calliope.
Heliconius numata is
a widespread species, found from Panama to
Bolivia.
Habitats
The butterfly occurs commonly at elevations between sea level and about 1000m. It
is usually seen singly, fluttering along trails in primary rainforest, but
also occurs in more open secondary forest.
Lifecycle
The eggs are orange, and laid singly on the leaf buds or tendrils of
Passiflora.
The
caterpillar, when fully grown is white with black spots, and branched black
spines along the back and sides. The head is orange, with a pair of
black horns.
The
chrysalis is brown with gold spots on the abdomen and thorax. There is a row of
short black spikes along each antenna, and longer spines along the back. The
head is bifid. The overall
impression is of a dead twisted prickly leaf, hanging from a stem.
Adult behaviour
Heliconius butterflies, including
numata, are characterised by
having a very delicate fluttering flight, particularly when hovering
around flowers.
Unlike other butterflies,
Heliconius feed on pollen as well as
nectar.
Studies of Heliconius ethilla in Trinidad have shown that
females deprived of pollen
only lay about 15% of the number of eggs laid by females that have
access to it. This probably applies equally to other
Heliconius species including
numata. The pollen from
Psiguria,
Anguria and Gurania flowers provides amino
acids
that cannot be obtained from other food sources, and contributes
greatly to the longevity of the butterflies - some
Heliconius species are known to live for up to 8 months as adults.
Experiments have proven that
Heliconius butterflies can learn home
ranges within which they can memorise the locations of nectar and
pollen sources, host plants and communal roosting sites. They are
able to plan the most efficient route by which to visit all nectar
/ pollen sources in the vicinity by using simple calculations akin
to what mathematicians call the "travelling salesman algorithm".
Erlich & Gilbert demonstrated
that individual butterflies memorise the location of particular
Psiguria plants, which they visit daily, following a
predefined circuit through the forest.
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