Butterflies of
Africa
Pierre's Acraea
Acraea encedana
PIERRE, 1976
Family - NYMPHALIDAE
subfamily -
HELICONIINAE
Tribe - ACRAEINI
Acraea
encedana,
Arba Minch,
Ethiopia
© Peter
Bruce-Jones
Introduction
There
are about 220 species in the genus Acraea, all
Afrotropical in distribution, with the exception of 3 species (
violae and issoria
from the Oriental region, and andromacha from Australia
& Papua New Guinea ). The vast majority of species are found in the forests and
savannahs of East Africa, while about 60 are found in West Africa.
All
Acraea species have elongate forewings and rounded hindwings. The wings
are thinly scaled and in many species are semi-transparent.
The scales wear off very easily so that insects more than 4 or 5
days old have a glassy or greasy appearance. The majority of species
have a predominantly brownish or greyish ground colour, marked with
bands or patches of red or orange. The basal area of the underside hindwings of most
species is marked with a pattern of small black spots.
Acraea encedana is distributed from Gambia to
Ethiopia and Sudan, and south to Angola, Malawi, and Mozambique.
Note : the Ethiopian form of
encedana is illustrated. A different form occurs
over much of Africa, in which the apical bar on the forewings and the ground
colour of the hindwings are both white. The latter form is considered to be a
Mullerian mimic of Danaus chrysippus.
Acraea
encedana,
Arba Minch,
Ethiopia
© Peter
Bruce-Jones
Habitats
This
localised species normally inhabits open grassy areas on lowland floodplains in
southern and western Africa. The form illustrated on this page is found at
altitudes of 1000m or higher in Ethiopia.
Lifecycle
The larval foodplant is
Desmodium salicifolium ( Fabaceae ).
Adult behaviour
Larsen, quoting Jiggins, states that
"all-female broods are common, with females constituting up to 95%
of local populations. Under such circumstances females aggregate
in narrowly limited areas to solicit males, in effect a female
lekking behaviour".
Both sexes nectar at
Tridax and other flowers.
|
