Megisto cymela
little wood-satyr

Megisto cymela is one of the most widely distributed satyrines in North America. It occurs in mixed woodlands and grasslands throughout most of eastern North American, from southeastern Saskatchewan down to the southern third of Texas, and east to the Atlantic. (Glassberg, 1999; Scott, 1986)

Megisto cymela occurs in mixed woodlands and grasslands throughout most of eastern North American, from southeastern Saskatchewan down to the southern third of Texas, and east to the Atlantic. (Glassberg, 1999; Scott, 1986)

The little wood-satyr lives where grasses and trees grow together: along edges of forest, in open woodlands, and in meadows near trees. The species is most populous where this habitat is combined with relatively alkaline soils. Larvae live on the grasses they eat, and probably hibernate in leaf litter. Adults tend to fly close to cover, especially in open fields. Males patrol for females, but tend to stay in shade. (Douglas and Douglas, 2005; Scott, 1986)

Megisto cymela is a medium-sized butterfly (wingspan 30-46 mm) with rounded wings (Douglas and Douglas, 2005). The dorsal surface (wings and body) are light tan-brown to medium brown. There are two yellow-ringed eyespots on the forewing, and one similar spot on the dorsal hindwing (some individuals have a second indistinct spot too). The ventral surfaces are lighter than the dorsal, with more vivid eyespots. Males and females have similar markings.

As in all species in the Nymphalidae, the first pair of legs is reduced and serves only sensory functions, the animals walk and perch with the other four. Also like most satyrines, little wood-satyrs have hearing organs in expanded veins near the base of each forewing.

Larvae are pale to yellow brown, and covered with a dense array of small tubercles, each supporting a hair. They have a strong dark mid-dorsal stripe, and brown marks along the sides. The larval body ends in two protuberances, like two short tails. (Douglas and Douglas, 2005; Scott, 1986)

Like most insects, the timing of little wood-satyr development is strongly affected by temperature. Eggs are laid by females in spring or summer. Larvae (caterpillars) hatch and begin feeding. They molt three times before the end of the growing season. If the climate requires it, they will hibernate at this stage, as 4th instar larvae. In the spring the surviving larvae pupate, suspending themselves head down for a few weeks. During this time they metamorphose into the adult form, which then emerges in spring or summer, depending on the location. Sources differ on the number of generations that are completed in one year in the extreme southern portion of the species' range. All agree that only one generation is completed in the north, but along the Gulf coast there may be 2 or 3 generations in a year. (Douglas and Douglas, 2005; Scott, 1986)

Longevity of this species has not been reported. Since adults cannot survive freezing temperatures, individual little wood-satyrs probably do not live for more than about 16 months.

Like many satyrines, adult little wood-satyrs have a distinctive hopping style of flight, seeming to bounce around trees and shrubs. They tend to stay close to cover as they fly. This is a relatively sedentary species, adults to not migrate.

Larvae are nocturnal, feeding at night and hiding on their host plants during the day. Adults are diurnal.

Where winter temperatures are too low for growth and development, larvae in the fourth instar hibernate. (Douglas and Douglas, 2005; Glassberg, 1999; Nielsen, 1999; Scott, 1986)

Adult little wood-satyrs use vision mainly to detect movement (of predators or con-specifics). In common with many insect eyes, their eyes can detect polarized light. They have chemical sensors in their antennae that they use to detect potential mates, and the host plants that their larvae will feed on. They most likely have taste receptors that sense the sugars and other nutrients in their food. This species and some of its relatives in the Satyrinae are unusual among butterflies in having an acoustic sensor (an "ear") in the veins near the base of their forewings. It's not clear what they are hearing with this structure, probably predator sounds. They do not use sound to communicate with each other.

Larvae have very poor vision, and no antennae, but probably do have a strong sense of taste, and are likely to be sensitive to vibrations as well. (Douglas and Douglas, 2005; Scott, 1986)

Larvae of Megisto cymela have been reported to eat several grass species in the wild: Kentucky bluegrass (Poa pratensis), orchardgrass (Dactylis glomerata), centipede grass (Eremochloa ophiuroides), and St. Augustine grass (Stenotaphrum secundatum). Captive animals in laboratories have eaten other grass species as well, so the species' natural range of host grasses may be wide.

Adults feed mainly on sap flows from trees, the "honeydew" secretions of aphids, and fluids from decaying mushrooms. They only occasionally take nectar from flowers. (Douglas and Douglas, 2005; Scott, 1986)

Caterpillars of Megisto cymela have been found eating several grass species in the wild: Kentucky bluegrass (Poa pratensis), orchardgrass (Dactylis glomerata), centipede grass (Eremochloa ophiuroides), and St. Augustine grass (Stenotaphrum secundatum). They may eat other kinds of grass as well, but not broad-leaved plants.

Adults feed mainly on sap flows from trees, the "honeydew" secretions of aphids, and fluids from decaying mushrooms. They only occasionally take nectar from flowers. (Douglas and Douglas, 2005; Scott, 1986)

We have no specific information on the predators of Megisto cymela. The species is not known to have any chemical defenses, but apparently relies on camouflage coloring and its powers of flight to avoid predators. Consequently, any insectivorous animal might prey upon them. (Douglas and Douglas, 2005; Scott, 1986)

This species has no known mutualist partners. Unlike some other butterflies, it is not a significant pollinator. Populations of M. cymela can be locally abundant, so it is probably an important food source for some insect-eating predators. It may also have significant effects on the density of its host plants, but this has not be demonstrated.

There are no known adverse effects of Megisto cymela on humans.

This species has no direct economic benefits for humans. It is however a common butterfly in many inhabited areas, so may add value to the environment. It may also be an important food item for desirable animals, such as songbirds.

This is a common and sometimes abundant species in most of its range. It is not considered in need of special conservation efforts or legal protection. (Douglas and Douglas, 2005; Glassberg, 1999; Layberry, Hall, and Lafontaine, 2002; Nielsen, 1999; Scott, 1986)