The Small Postman, Heliconius erato
The Small Postman is common and widespread throughout Central and South America. The forewings are black with a large red band, while the hindwings are black at the base and yellow along the top.
The Small Postman looks almost identical to its co-mimic, the Postman (Heliconius melpomene). The best way to distinguish these two species is to look on the ventral side of the hindwing. The yellow line extends to meet the margin of the wing on the Small Postman (H. erato), whereas on the Postman (H. melpomene), the yellow line does not meet the margin of the wing.
Adults feed on nectar from Lantana spp. and many other flowers, and collect pollen from Psiguria spp. Adults learn and memorize the location of Psiguria plants (also known as Amazon cucumber). They then return to them daily, following a pre-defined route through the forest. This is referred to as ‘trap-line’ feeding – it’s also how they earned their name of “Postman!”
The Postman butterfly belongs to the group of Longwings (Heliconius genus), which is unique for their longevity of life. Most butterflies live an average of 2 – 3 weeks, but the Longwings can live up to 6 months due to a higher protein diet than most butterflies, which can only drink nectar from flowers. When Longwings drink nectar from a flower,they can also ingest the pollen when it gets stuck to the proboscis.
Adults have a delicate, erratic flight, and can be found in the forest lowerstory. Small Postman caterpillars are white with black and orange spots. They feed on passion vine (family: Passifloraceae).