Zebra Longwing Butterfly (Heliconius charithonia)

Description

These monomorphic butterflies come in a single form without any color morphs. They are medium in size with elongated, narrow wings, as evident by their name, ‘longwing,’ and long, black antennae. The dorsal part of their wings is black, marked with white and yellow stripes. The ventral side has a similar pattern but appears paler. The only addition is the red spots to the side. Their wingspan range between 70 and 100 mm.

Distribution: Central America, South America, Mexico, and certain parts of the United States like Florida and south Texas; they may inhabit Nebraska, South Carolina, and New Mexico in the warmer months

Habitat: Prefers warm, and damp tropical areas, inhabiting fields, edges, moist forests, thickets, and hammocks

Do they bite: No; the venomous spines of the larvae aren’t venomous too

Lifespan: Around a month

Predator: Bugs, mammals, amphibians

Subspecies

• H. c. charithonia (Ecuador)
• H. c. bassleri (Colombia)
• H. c. simulator (Jamaica)
• H. c. tuckeri (Florida)
• H. c. churchi (Hispaniola)
• H. c. antiques (Antigua)
• H. c. vazquezae (Mexico-Panama)
• H. c. ramsdeni (Cuba)

Behavior and Characteristics

Social

Roosting is common among these butterflies, mostly occurring at night in groups as large as 60. This unique strategy is adopted to stay safe from predators and remain warm. They return to the same roosting site each night that commences 3 hrs before sunset and ends in 2hrs post sunrise. A hierarchy is maintained, with the older butterflies getting the privilege of choosing the best roosting site. Before roosting, they communicate with community members by sitting close to each other and chasing one another during basking or fluttering. 

Vocalizations

They vocalize through a creaking sound when disturbed. These butterflies even wiggle their body simultaneously.

Intelligence

They are reputed because of their intelligence. Because of their sharp memory, these butterflies remember their host plants and return to the same food sources they previously fed on.

Sharp eyesight  

The visual purple or UV rhodopsins in their eyes help them identify the yellow pigments. Hence, these butterflies can easily spot tendrils, dry leaves, and twigs when preparing to roost. Their sharp eyesight also helps them locate conspecifics roosting in other sites. 

Chemical cues  

Chemical cues comprising volatile and nonvolatile substances help these butterflies identify conspecifics at a shorter distance.

Mating

These butterflies follow a unique technique of pupal mating. The male zebra longwing begins searching for mates even before they emerge from the chrysalis. Finding the chrysalis is challenging, yet the male tries to locate it via tactile, olfactory, auditory, and visual cues. The pupae mostly camouflage themselves among leaves and do not have sexual pheromones, leaving olfactory cues the only option for males to search them. As soon as the females emerge from the pupa, two or more males fight against each other to seek their prospective mate. They display various fighting techniques, like throwing off their foe using their antennae and head.

The winner chooses his mate and even sprays a spermatophore on the female so that she becomes less attractive to other mates trying to seek her.

Feeding

The adults feed on pollen and nectar, which helps them live for three months in the wild and about five months in captivity. Pollen feeders appear distasteful to the predators. They even look brighter and more intimidating to their enemies. The choice of their home range depends on their collection of pollen plants. While extracting the pollen, the adults coil their elongated appendages or proboscis and insert them inside the flowers. The pollen is digested immediately after ingestion. Females that don’t feed on pollen will have a low reproductive rate over pollen feeders.

The larva’s diet comprises corky-stemmed passionflower, two-flower passionflower, and yellow passionflower.

Life Cycle

1. Egg Stage

After mating, the female goes on to lay eggs on passionflower plants, around 5-15 at a time. The yellow eggs are elongated with a ribbed pattern.

2. Larva Stage

They appear white with black spots and soft black spines on their back. The caterpillars go through five molts before entering pupation.

3. Pupa Stage

The pupae have a brown body with two elongated ridges on their head.

4. Adult Stage

There is hardly any difference between males and females.

Damage Caused by Them

They aren’t that harmful, yet the caterpillars often strip the passion flowers of their protective hairs, causing some damage.