Butterflies of
the Amazon and Andes
Gulf
Fritillary
Agraulis
vanillae
LINNAEUS, 1758
Family - NYMPHALIDAE
subfamily -
HELICONIINAE
Tribe
- HELICONIINI
Agraulis vanillae ©
Ken Childs
Introduction
The genus
Agraulis comprises of 2 known species
- vanillae, and a currently un-named
species which was discovered in Peru by Lamas in 2003.
Agraulis vanillae is distributed from
the USA to Paraguay and Argentina. It is found on most of the
larger Caribbean islands, and also occurs on the Galapagos Isles.
Habitats
This species is
found mainly in semi-open habitats including forest edges,
scrub, roadsides, parks and gardens, at altitudes between sea
level and about 1000m.
Lifecycle
The eggs are
yellow, and laid singly on the leaves, tendrils and buds of the
foodplants.
The caterpillar
when fully grown is greyish-black, speckled with cream dots, and
covered in black spines. Along the back is a pair of reddish
lines, and a broad broken red line runs along each side. It
feeds nocturnally on Passiflora and
Tetrastylis ( Passifloraceae ).
The chrysalis
resembles a twisted dead hanging leaf. It is marbled in shades
of olive-brown, with small silvery streaks along the dorsal edge
of the wing cases. There is a keel projecting from the thorax,
and a row of short knobbly tubercles along the back of the
abdomen.
Adult behaviour
Males sometimes
imbibe moisture from damp sand or soil, but like the females are
more often seen nectaring at Lantana
and other red flowers. Unlike many other Heliconiines, they do
not sequester pollen.
The courtship
behaviour is almost identical to that of
Dryadula phaetusa - the male chases after his prospective
mate until she settles on the ground. He then flutters and
hovers just above her, prior to settling beside her. If she is
receptive she remains motionless, and the male then half opens
his wings and flutters them very rapidly for a few seconds to
direct pheromones towards her antennae. This has the effect of
placating her. The male then curves his abdomen around to make
contact and copulate.
In cases where
the female is unreceptive she outspreads her wings and raises
her abdomen. This serves 2 purposes - firstly it acts as a
visual rejection signal, and secondly it physically prevents the
male from copulating. It is possible that at the same time the
female emits pheromones that may carry a chemical repellent to
further discourage the male.
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