Skippers, Family Hesperiidae

Habits and Traits of Skippers

A skipper.
A skipper butterfly, Parnara guttata. Getty Images/Moment/YunhyokChoi

The skippers can be frustrating to identify to species. They're fast moving, and many share similar marking and color patterns, making it almost impossible to identify them with any degree of certainty in the field. It's best to begin your study of skippers by learning the traits and behaviors of the family Hesperiidae, outlined here.

Description:

The skippers get their common name from their quick but erratic flight.

These small to medium butterflies look like they're skipping from place to place. Most skipper butterflies are some combination of brown, orange, and cream, so someone unfamiliar with the family Hesperiidae might confuse a skipper for a day-flying moth.

Most skippers have stout, hairy bodies, and small, pointed wings that are usually held on different planes while at rest. The hind wings rest flat, while the forewings are held slightly open at an angle (see photo). In skippers, the antennae usually end in a hook or curve, and are separated at the base, so that they appear to attach to each side of the head. The family Hesperiidae is differentiated from other butterfly families by the wing venation pattern. In skippers, the radius in the forewings consists of five simple (undivided) branches, each originating from the discal cell.

If you're looking for skipper caterpillars, you'll need to be patient and persistent.

They typically feed at night, and rest inside shelters constructed from leaves and silk during the day, where they are hidden from predators (and insect enthusiasts). Skipper caterpillars have enlarged heads, constricted necks, and tend to be slightly thicker in the middle of the abdomen.

The skipper family is divided into four subfamilies:

  • Pyrrhopyginae - firetip skippers
  • Pyrginae - spread-wing skippers
  • Heteropterinae - skipperlings
  • Hesperiinae - tawny skippers, grass skippers, and giant skippers

In some references, the giant skippers are classified in their own subfamily (Megathyminae), but I've followed the subfamily scheme found in the latest edition of Borror and DeLong's Introduction to the Study of Insects.

Classification:

Kingdom – Animalia
Phylum – Arthropoda
Class – Insecta
Order – Lepidoptera
Family - Hesperiidae

Diet:

As a group, skipper caterpillars feed on the foliage of a wide variety of plants. Spread-wing skippers feed on various legumes, herbs, and trees. Grass skipper caterpillars feed on grasses, as you probably guessed, and sedges. The larvae of giant skippers feed on agave, yucca, and similar related plants. Skipper butterflies take nectar from flowers.

Life Cycle:

Skippers undergo complete metamorphosis, just as all butterflies do. Females lay hemispherical eggs, almost always singly, on the foliage of a host plant. Skippers usually overwinter as caterpillars, tucked away in leaf shelters or in silk cocoons. Skipper pupae may hang or extend from a twig or branch, supported by a silk girdle.

Special Behaviors:

Most skipper larvae construct the leaf shelter by first chewing two parallel cuts, moving from the leaf edge to its center.

This creates a "tab" that the caterpillar can then pull and fold over, to form a pocket of sorts. The caterpillar then tacks the folded portion down using silk to secure it in place. Grass skipper larvae usually roll a leaf instead.

Range and Distribution:

The skippers number more than 3,500 worldwide, with the majority of species living in the tropics. Almost 300 species inhabit the U.S. and Canada, most of which live in the southern U.S. About one-third of North American butterflies belong to the family Hesperiidae.

 

Sources:

  • Borror and DeLong's Introduction to the Study of Insects, 7th edition, by Charles A. Triplehorn and Norman F. Johnson.
  • Kaufman Field Guide to Butterflies of North America, by Jim P. Brock and Kenn Kaufman.
  • Caterpillars of Eastern North America, by David L. Wagner.
  • Family Hesperiidae, Idaho Museum of Natural History, Idaho State University. Accessed February 12, 2013.
  • Hesperiidae, Butterflies and Moths of North America website. Accessed February 12, 2013.