Butterflies of the
Amazon and Andes
Family - RIODINIDAE
subfamily - RIODININAE
Tribe - EURYBIINI
Eurybia species, probably molochina,
Madre de Dios, Peru
© Adrian Hoskins
There are about 20 Eurybia Underleaf
butterflies, which occur variously throughout the neotropics from
Nicaragua and Honduras to southern Peru and Bolivia.
All have greyish or brownish uppersides with a series of squarish
submarginal markings. Several species e.g.
have a blue iridescence across the upperside hindwings. Almost all
species have a prominent orange-ringed false eyespot in the discal
cell of each forewing. Only halimede,
and the falcate-winged
and pergaea lack these eyespots, and
hence are commonly known as "blind" underleafs.
all species the upperside pattern is repeated on the under surface,
but the under surface is paler, and the markings less conspicuous.
Eurybia characteristics include
metallic green eyes and an extremely long proboscis that is almost
twice the length of the body, enabling the butterflies to reach deep
into flowers for nectar.
Eurybia molochina is found in Brazil
and eastern Peru.
This species, and others of the genus, occur in primary rainforest
at elevations between sea level and about 1000m. They are never seen
in open sunlit areas, instead preferring the darkness of the forest
I have no data
regarding molochina but the lifecycle
is likely to be similar to that of other
Eurybia species as follows: The eggs are like flattened
lozenges and are laid singly on the stems and leaves of
Ichnosiphon, Maranta, (
Marantaceae ), Costus and
Renealmia ( Zingiberaceae ). The larvae
are maggot-like, and feed on the flowers, not the foliage. Older
larvae can be found in ant nests within sheaths surrounding the
stems of the foodplants. They are constantly attended by ants which
milk them for a sugary substance secreted from a dorsal gland. The
larvae are parasitised by Rogas and
other Braconid wasps.
The proboscis on
the butterflies is very long, and there is a correspondingly
long-proboscis casing on the pupa, which extends about 2cms beyond
the tip of the abdomen.
Eurybia adults are very secretive by
nature, spending very long periods resting under the leaves of low
growing vegetation, always with wings spread open, cheekily peering
out to play peek-a-boo with only their eyes and antennae visible to
observant passers by. They are extremely wary and have excellent
eyesight. They can detect the tiniest movement and instantly dash out
at high speed to investigate any passing butterfly, then almost
instantaneously return to resettle under the same leaf, or one very
nearby. The degree of agility apparent when they fly into the
vegetation, flip upside-down and settle under a leaf is quite amazing
never observed any form of prenuptial ritual in
Eurybia species, and assume that courtship is extremely swift
and leads to almost instant copulation. I have on occasions found
copulated pairs of Eurybia at rest
beneath low foliage with wings outspread.
Eurybia species have an extremely long
proboscis which enables them to probe for nectar into the deep flowers
of Heliconia plants. The easiest way to
observe the butterfly is to find an isolated
Heliconia growing in the forest, and to wait nearby until one
DeVries records that large numbers of
Eurybia adults are eaten by Anolis and