Megathymus yuccae (Boisduval and Le Conte, [1837])
Yucca Giant Skipper
NatureServe Global Rank: G5
Virginia State Rank: SH
VA DGIF Tier: IV
Federal Legal Status: None
Virginia Legal Status: None
Description: The Yucca Giant-Skipper is the largest species of Skipper in the area. Both sexes are mainly brown on the dorsal surface with a yellow patch crossed by brown veins near the edge of the front wing. There is a smaller white wrist bracelet marking at the leading edge of the front wing, with a similar but smaller yellow marking near the midpoint of the leading edge. The dorsal hind wing is mainly brown with yellow lining the outer margin of the wing. The females have an extra yellow spot line just inside this. The ventral hind wing is mainly brown with white frosting towards the outer margin. The leading edge of the ventral hind wing displays a white tooth-like marking.
Similar species: While the Yucca Giant-Skipper is similar in appearance to other members of the Megathymus genus, none occur in Virginia so this species should not be confused with any others.
North American Range: The range of this skipper species extends from Southeastern Virginia to Coastal Florida, across the southern US to the west coast. There is a known occurrence in Powhatan County, Virginia, however, it is likely this population was introduced on transplanted yucca plants. Evidence of breeding (larval tents) have been found in southeastern Virginia where it is likely a natural occurrence.
VA Observations by Locality: Suffolk, City of | Virginia Beach, City of
Flight season and broods: This species only has one brood that is active between the months of February and May.
Habitat and Food Plants: This skipper prefers to make its home in pine flatwoods, sand hills, granite outcrops, old fields, dunes, and coastal forests. The host plant and an open area seem to be governing factors in population success. All species in the Yucca family are considered host plants of the Yucca Giant-Skipper. Yucca filamentosa is the most common plant used in the Virginia area.
Behavior and Ecology: The males patrol at very high speeds along corridors of host plants while the females are much less active. Neither sex is known to visit flowers for nectar but males will occasionally stop in search of females or to imbibe moisture at moist earth. The larvae start by eating the vegetation of the Yucca and then bore into the stem and eat the contents of the stem and root, deep into the ground. They create 'tents' at the crown of the plant where they glue together dead leaves and deposit feces. They pupate in their tunnels and the pupa can move up and down the plant through these. When it nears emergence time, the pupa locates itself in the crown of the plant or the tent. This species can most easily be found by searching for these tents on yucca plants.
Population trend and potential threats: Although not commonly seen aside from the targeted trip, this species is relatively common in the appropriate habitat. The maintenance of open forests containing yucca would be the main requirement to keep this species stable.
Management practices: There are no current management plans for the Yucca Giant-Skipper.
References: Cech, R. and G. Tudor. 2005. Butterflies of the East Coast. Pg. 319. Princeton University Press.
Glassberg., J 1999. A Field Guide to the Butterflies of Eastern North America. Pg. 71. Oxford University Press.
Opler, P. A. 1992. A Field Guide to Eastern Butterflies. Peterson Field Guides
Pyle, R. M. 1981. Field Guide to North American Butterflies. National Audubon Society.