Butterflies of Zihuatanejo

SUPERFAMILY PAPILIONOIDEA

-Subtribe Moncina

-Saturnus Skipper (Callimormus saturnus)

Callimormus saturnus, commonly known as the Saturnus Skipper, is a small-sized skipper butterfly in the family Hesperiidae. The wings are generally dark brown to black, marked with pale or translucent spots, especially on the forewings. These markings can vary but often form a somewhat scattered pattern rather than a continuous band. The underside is usually lighter brown with subtle patterning, helping the butterfly blend into its surroundings when at rest. This species occurs in Mexico and Central America, where it inhabits tropical forests, woodland edges, and shaded clearings. Adults are often seen perching on leaves or flying quickly along forest paths, occasionally visiting flowers or feeding on moisture from soil and organic matter.

Diet

Adults feed primarily on flower nectar and are typical small grass skippers, often visiting low-growing flowers.
The caterpillars feed on grasses (Poaceae).
The species is considered somewhat oligophagous, meaning its larvae use several related grass species rather than being restricted to a single host.

Range

Callimormus saturnus has a remarkably broad tropical distribution, ranging from eastern and western Mexico through Central America and South America to southern Brazil and Paraguay. Its type locality is in Venezuela.
Around Zihua, it would be a plausible species in suitable grassy habitat and should probably be considered occasional to locally common, particularly where native grasses grow in openings and along forest margins.

Habitat

Saturnus Skippers occur in tropical and subtropical woodland, forest margins, grassy clearings and secondary vegetation.
They can occur in moist forest as well as more open disturbed habitats.
Around Zihua, look for them along grassy roadsides, forest clearings, stream margins, open woodland and edges of tropical deciduous forest, especially where Panicum and other grasses are abundant.

Size

This is a small grass skipper, generally around 25–30 mm in wingspan.
The wings are brown to dark brown with subtle lighter markings, giving the butterfly a rather subdued appearance. Like many grass skippers, it can be surprisingly difficult to notice when perched among grasses.