see List of species Hedylidae, the "American moth-butterflies", is a family of insects in the order Lepidoptera, formerly representing the superfamily Hedyloidea.

In 1995, Weller and Pashley[7] found that molecular data did indeed place Hedylidae with the butterflies and a more comprehensive study in 2005[8] based on 57 exemplar taxa, three genes and 99 morphological characters, recovered the genus Macrosoma as sister to the ("Papilionoidea" + Hesperioidea).

However, the most recent phylogenetic analyses shows that skippers are true butterflies and therefore within the clade Papilionoidea, whereas the hedylids are a sister group that may be closely related to the obtectomeran moths.

[10][11] Since there are no obvious gaps between supposed species groups, according to basic morphological structure, Scoble (1986) synonymised the five pre-existing genera of Hedylidae (33 of which had been described in Phellinodes) into the single genus Macrosoma.

The eggs of hedylid moths have an upright configuration and are variable in shape: in Macrosoma inermis they are particularly narrow and spindle-shaped,[17] resembling those of some Pieridae, and in the case of M. tipulata they are more barrel-shaped,[18] like certain Nymphalidae.

The abdomen is very long and slim, like many Neotropical butterflies of the subfamilies Ithomiinae and Heliconiinae, hence the name of one Macrosoma species "heliconiaria".

[19] Unlike the family Geometridae, in which they had been placed by the geometer expert L.B.Prout, hedylids lack tympanic organs at the base of the abdomen, but have them on the wings (see under Behaviour).

[36] The resting posture is often at a curious angle,[37] with the thorax tilted and the posterior edge of the hindwings nearly touching the substrate (Scoble, 1986).

The larvae which lack the prominent horns in the first instar tend to rest on the midrib of the leaf and often skeletonise leaves or at either side produce an untidy patchwork of holes.

The "green lizard caterpillar" Macrosoma tipulata[42] attacks an economically important local fruit tree "Cupuaçu" (Theobroma grandiflorum) in Brazil and can defoliate saplings; the biology of this species has been studied and illustrated in some detail.