Butterflies of
Thailand, Malaysia &
Borneo
Nigger
Orsotriaena medus
FABRICIUS, 1775
Family - NYMPHALIDAE
subfamily -
SATYRINAE
Tribe - SATYRINI
subtribe - HYPOCYSTINA
introduction
|
habitats |
lifecycle |
adult behaviour
|
 |
|
Orsotriaena medus,
Taman Negara,
West Malaysia |
Introduction
Regrettably the popular name "Nigger" was coined for this
species in colonial times, and can cause unintended offence, but
in the absence of an alternative we continue to use it here.
The genus
Orsotriaena comprises of a single
species medus. It bears a
superficial resemblance to Mycalesis
species but on the underside has only 2 ocelli on the forewing,
and 3 on the hindwing. The upperside is dark brown and unmarked.
This is a very
common and widespread species found from India and Sri Lanka to
Thailand, and south through Malaysia to Sumatra, Borneo,
Sulawesi, Timor, Papua New Guinea and northern & eastern
Australia.
Habitats
The Nigger is found in disturbed grassy habitats including
forest glades, roadsides and riverbanks at altitudes between sea
level and about 250 metres.
Lifecycle
The egg is shiny, spherical and straw-coloured. It is laid
singly on blades and stems of grasses.
The caterpillar when fully grown is a dirty whitish colour, with
a faint suffused dark stripe along the back. The body segments
are vertically wrinkled, and covered with tiny tubercules. There
is a pair of long pinkish caudal prongs projecting backwards
from the anal segment. The head is pale brown and bestowed with
a pair of long chestnut brown horns. The caterpillar feeds
nocturnally on Oryza sativa,
Saccharum officinarum and other
grasses.
The chrysalis
is yellow, stained with brownish, and has a long horn extending
forward from the head. It looks rather like a tiny banana, and
is attached by the cremaster to the underside of a grass blade,
or to a nearby stem.
Adult behaviour
The butterflies are mainly active at dawn and dusk, or on
overcast days, but can be seen also in sunny conditions.
|
