Satyrodes eurydice

Type: invertebrate

Status: not ranked

Species Guide

Eyed brown

Satyrodes eurydice

Species Type: invertebrate

Conservation Status: not ranked

IDENTIFICATION

The eyed brown has a wingspan of approximately 1 ½ to 2 ½ inches. The upperside of the forewing and hindwing is pale brown, getting darker toward the body. Each wing has a row of black eye spots toward the edge of the wing. These spots are larger on the hindwing. The undersides of the forewing and hindwing are pale brown and have “jagged” dark lines across them. There is a notch pointing inward on the basal line of the hindwing. This notch differentiates the eyed brown from the similar Appalachian brown (Satyrodes appalachia).

Eyed brown larvae are a bright green with lateral yellow and green stripes. There are pairs of red horn-like structures on the head and tail.

 

Distribution & Habitat

The range of the eyed brown covers eastern North America from Nova Scotia south to Delaware and west to Saskatchewan and Nebraska. In New Jersey, the eyed brown is found in the northern part of the state, with most reports coming from Sussex County.

The eyed brown occupies open wetlands including sedge meadows and cattail marshes. It can also be found along slow moving streams where there is growth of tall grasses.

Diet

The larval host plants include various sedges (Carex spp.). Adults will occasionally feed on the nectar of flowing plants such as swamp milkweed (Asclepias incarnate). More often, they feed on rotting fruit, sap, and bird droppings.

Life Cycle

The female lays eggs singly on multiple leaves. The larvae consume the leaves of the host plant and develop until the third or fourth instar stage, then stop maturing to overwinter. When the weather warms, they form a chrysalis and emerge for a flight period that lasts from early June to late July.

Current Threats, Status, and Conservation

Despite its large range, the eyed brown is found on a local basis. Due to its special habitat needs and small range in the state of New Jersey, it is recommended as a “special concern” species. This means that it is especially vulnerable to changes in habitat. Current focus is on monitoring populations and considering conservation needs.

Most of these conservation efforts nationwide focus on a subspecies of the eyed brown, the smoky eyed brown (Satyrodes eurydice fumosa). The smoky eyed brown is found in Colorado, Illonois, Iowa, and Nebraska and is considered threatened throughout its range. Current goals involve studying the species in order to develop a conservation plan.

In 2015, the New Jersey Endangered and Nongame Advisory Committee recommended a Special Concern status for this species within the state, but no formal rule proposal has been filed to date.

 

References

  • Butterflies and Moths of North America
  • Massachusetts Audubon Society
  • North American Butterfly Association, New Jersey Chapter
  • U.S. Fish and Wildlife Service

Text written by Kathleen Wadiak in 2015.

Scientific Classification

  • Kingdom: Animalia
  • Phylum: Arthropoda
  • Class: Insecta
  • Order: Lepidoptera
  • Family: Nymphalidae
  • Genus: Satyrodes
  • Species: S. eurydice