Ruellia prostrata is a new larval host plant for the Blue moon butterfly

Hypolimnas bolina, the great eggfly, common eggfly,varied eggfly or blue moon butterfly is a species of nymphalidae.

Blue moon male : CUBE Homelab ,Cherukkad,Kozhikode.

(Nymphalidae - Wikipedia) butterfly .(Wikipedia ).

The lifecycle comprises eggs, caterpillar, pupa, and adult stages.

After about four days, the eggs hatch.

The head bears a pair of long, branched black horns. The body surface is also covered with long, branched, orangish-black spines

Hypolimnas bolina - Wikipedia.

I have not observed the eggs of the Blue Moon butterfly; instead, I collected the caterpillar of the Blue Moon from my homelab.

UC1 caterpillar emerges with Bluemoon Male,September 2022

Check the following links for more photoes and videos :

UC2 caterpillar emerges with Bluemoon female .

UC2 butterfly
UC2 Butterfly Waving its wings .
Place:Cherukkad,Kozhikode .

UC2 butterfly
UC2 Butterfly Waving its wings .
Place:Cherukkad,Kozhikode .

I observed the lifecycle of the Blue Moon butterfly on a plant named Ruellia prostrata, which belongs to the family Acanthaceae.

Bell Weed is a prostrate perennial herb, with stems often rooting at the nodes. Ovate green leaves, 2-10 cm long. Leaf stalk is 5-30 mm long. Flowers occur solitary in the leaf axils, Sepals 5, linear, 6-10 mm long. Flowers are violet blue to occasionally nearly white, 2.4-3.2 cm long, the petals slightly spreading. Capsules club-shaped, 1.5-2 cm long, densely covered with fine hairs.

Ruellia prostrata - Bell Weed.

Identification of plant in my Homelab .

Ruellia prostrata is a known larval host plant for two butterflies:

Zizula hylax – Tiny Grass Blue

Junonia iphita – Chocolate Pansy

I observed the complete lifecycle of the Blue Moon butterfly, both male and female, in Ruellia prostrata.

I have two sets of observations: one from September 2022 and the other from September 2023.

The interesting part is that yesterday, I came across a caterpillar from the same plant, Ruellia prostrata.

When I compared this recent data with the previous data something striking:

1)Both caterpillars were found on Ruellia prostrata.

2)I collected both caterpillars in the month of September from my homeland, and yesterday, I encountered the same type of caterpillar again. Today, it has entered the pupal stage.

Place :Cherukkad,Kozhikode .
Time :10.30pm

Place :Cherukkad,Kozhikode .
Time :10am

The intersting thing about blue moon butterfly is that the female of blue moon mimicking common crow .

Common crow laying eggs on Ficus plant .

Place :Balussery ,Kozhikode .
Time :10am

Video showing male & female Blue moon butterfly ,sorry for the less clear video .

Place :Cherukkad ,Kozhikode .
Time :4pm


Have you checked all the larval host plants of the great Eggfly in website of ifoundbutterflies?

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Could not find the video Caterpillar eating the leaf of the new host plant.Caterpillar if found moving about on a plant it could be to find a site for pupation so eating the leaves of the new host plant claimed by you has to be shown @Theertha

@magpie i found butterflies shows these are the butterfly which choose Ruellia as a host plant .


Is there any other site to confirm ?

video showing leaves are eaten by the caterpillar.