Hypolimnas bolina, the great eggfly, common eggfly or the blue moon butterfly is a species of nymphalid buttfly.
H. bolina is a black-bodied butterfly with a wingspan of about 70–85 millimetres (2.8–3.3 in). The species has a high degree of sexual dimorphism. The female is mimetic with multiple Morphs.
The upperside of the wings is jet black, offset with three pairs of white spots, two on the forewing and one on the hindwing. These spots are surrounded by purple iridescence. In addition, the upperside of the hindwing bears a series of small white dots.
The upperside of the wings of the female is a brownish black and does not have any spots like those of the male. The edges bear white markings which are similar to those of the Common Indian Crow.
H. bolina is known for maternal care, with the females guarding leaves where eggs have been laid. Males are also very territorial and site fidelity increases with age. Territories that enhance the detection of females are preferred. The female hovers over a plant to check for ants which will eat her eggs. After selecting a plant which has no ants on it, she lays at least one but often two to five eggs on the undersides of the leaves. Race bolina breeds on sida rhonbifolia, Elatostemma cuneatum,Portulaca oleracea,, Lapoprtea interrupta,Triumfetta pentandra, and Asystasia species. Other hosts include Elatostemma cuneatum ,Fleurya interrupta,Pseuderanthemum varibile, and Synedrella nodiflora. They are also known to feed on Urtica dioica and Malva species.
Hypolimnas bolina is frequently polymorphic and most forms are then non-mimetic. In areas where it resembles Euploea the butterfly has usually been designated a Batesian mimic. The supposed model feeds on Asclepiadaceae and Moraceae only, two families of plants of which various species possess emetic, toxic and purgative properties, whereas the foodplants of Hypolimnas include examples from eleven families, only a few of which are irritant or toxic.the larva of H. bolina feeds on Ipomoea batatas, the butterfly stores cardio-active substances.
The eggs are a pale, glassy green with longitudinal ridges except on the top.
After about four days the eggs hatch. The catepillars immediately disperse. They are black with an orange head. The last segment is also orange. The head bears a pair of long branched black horns. The body surface is also covered with long, branched, orangish black spines. These spines look whitish and transparent immediately after moulting, but soon become the usual orange. In later instars the spiracles are surrounded by thin, dirty orange rings. Infection by wolbachia bacteria is known to exclusively kill male specimens.
The pupa is suspended by just one point. It is brown with a grey tinge on the wings. The abdominal segments have distinct tubercles. The surface of the pupa is rough. The butterfly emerges after seven to eight days as pupae (female development is always a bit longer).
No species-specific conservation measures are currently in place for this species, although part of its restricted range lies within the Mount Nimba Strict Nature Reserve. Further research to better quantify the distribution of this poorly investigated species would benefit protection of this poorly known species and highlight the scale of threats to the species.