The Small Postman has many forms and subspecies over its range; most of the forms are mimicked by the Common Postman as well as other Heliconian Butterflies such as Cydno.
A large number of Longwing butterflies mimic this basic red,
rayed pattern on black as a warning to potential predators. In addition to the Postmen, H. erato (eg subspecies emma, lativitta) and H. melpomene (forms/subspecies: aglaope, malleti, penelope, thelxiope, vicinus),
the following have a form similar to some degree: H. burneyi, H. demeter, H. elevatus, H. timareta, H. xanthocles, Neruda aoede and Eueides tales. Some H. cydno subspecies/forms also have this type of pattern and Laparus doris (also called H. doris) has a passing resemblance. There are also others.
The white forewing bar(s) varies considerably.
The butterfly above is one of the several with only one white bar on each forewing rather than two.
This version above is entirely red and pink.
The red Postman-type above is relatively small.
The variation on the theme above has a Cydno-like, forked white bar and underside hind wing. It may be a Cydno subspecies form or a Postman-Cydno hybrid.