Neonympha mitchellii mitchellii, Mitchell's Satyr Butterfly |
|---|
 The Mitchell’s Satyr Butterfly (Neonympha mitchellii mitchellii) is in the order Lepidoptera, and the family Nymphalidae. Its wingspan ranges from 1.5 to 2.0 cm, females generally being larger than the males. The dorsal, or upper side of the wings, is unmarked and dark brown. The ventral, or lower side of the wings, is most distinctly characterized by a linear arrangement of eyespots on the forewings and hindwings. Certain flight characteristics can distinguish it from similar species. Mitchell’s Satyr generally flies low in a slow, bobbing manner, as opposed to rapid and erratic flight. Populations of this butterfly have been exclusively found in fens dominated by sedges. Fens are peatlands fed by groundwater and generally are not as acidic as bogs. The distribution of fens is fairly limited, occurring in glaciated areas of North America. Little is known about the life history of Mitchell’s Satyr. The butterfly has not been seen ovipositing in nature, but the primary host plant is most likely the sedge, Carex stricta. This is based on studies that have shown females to oviposit in captivity on these particular plants. Not only that, but in the field the butterfly has always been found to be in association with C. stricta. After the larva hatches, it presumably consumes the primary host plant and then hibernates under the snow when it reaches the fourth instar. It then emerges in the spring and resumes development. Adult males emerge before females, and the life span of the adult has been recorded to be about two weeks. It is uncertain as to if the adults eat or drink in that time period. At the present, 15 populations of this butterfly are known. Thirteen of them are distributed throughout southern Michigan, and 2 of them are in Northern Indiana. Historically, thirty or more populations have been recorded, possibly occupying New Jersey, Ohio, and Maryland. Neonympha mitchellii mitchellii was listed as endangered in 1992. A recovery plan was proposed in 1998 that would span for an estimated nine years. During this time period, about 1.1 million dollars would presumably be spent on recovery. In 2007, the species may be delisted if there’s a total of 25 viable populations. There are a few possible reasons for endangerment. First and foremost is habitat loss. Second is the disruption of ecological processes such as natural fires, or wetland drainage due to human intervention. Lastly, overcollecting may have contributed to population decline. Proposed actions to help conserve this butterfly include, but are not limited to the following. First of all, existing populations should be monitored and the search for other population will continue. Also, more research must be conducted on the butterfly’s life history. This will allow conservation measures to be more effective so that populations can be reestablished in areas where Mitchell’s Satyr was known to exist historically. |
Resources:
|
Written by: Juliane Deacutis 2004 Updated: 2008 |
Image credit: Entomological Consulting Services, Ltd. |
