Thailand, Malaysia &
Family - NYMPHALIDAE
subfamily - APATURINAE
Tribe - APATURINI
The Golden-eye, also known as the Courtesan, is
one of 3 members of the genus Euripus,
which is placed in the Apaturini - the same tribe to which the
Purple Emperor of Europe belongs.
male, illustrated above, is regarded as a Batesian mimic of the male
of Euploea radamanthus, a Danaine which
has a similar pattern of white rays in its underside. This Danaine,
known as the Magpie Crow, has been demonstrated to be toxic to
birds, and is mimicked by several non-toxic butterflies including
nyctelius and the Papilionid
female of nyctelius produces 2 distinct
forms or morphs - f. isina, on the
upperside is marked with white bars on a black ground colour, again
just like the
of Euploea radamanthus. Another of the
nyctelius female morphs is
euploeoides, which as its name suggests
is also a Euploea mimic, but in this
case it is imitating the
of radamanthus, which has extensive
areas of white on its hindwings. Both sexes of
nyctelius possess distinctive golden-yellow eyes.
Euripus nyctelius is found in Sikkim,
Myanmar, Thailand, West Malaysia, Singapore, the Philippines,
Sumatra, Borneo and Java - a range that coincides exactly with that
of Euploea radamanthus.
This species is found in primary rainforest at
elevations between sea level and about 500 metres.
I have no information about the egg stage, but
based in related genera it is likely to be spherical and laid singly
on leaves of the foodplant. The larva is green with a series of pale
diagonal stripes along the sides. It is plump, and tapers strongly
towards the tail. The head is adorned with a pair of forward curving
horns. It feeds nocturnally on Gunpowder tree
Trema orientalis ( Cannabaceae ).
The chrysalis is pale green with whitish diagonal stripes along the
sides, and bears a remarkable resemblance to a leaf, complete with a
"midrib" and "veins". It is suspended by the cremaster from a leaf
of the foodplant.
Males are not
uncommon but are elusive in behaviour. They tend like other
Apaturini to spend most of their time on territorial perches high in
the tree tops, and give chase to other males which enter their
domain. Occasionally they descend to imbibe mineralised moisture
from pebble-strewn river beaches. Females are seen much less
frequently, usually when flying around low vegetation.
male, Taman Negara, West Malaysia ©