Butterfly Atlas Species Accounts

Butterfly Atlas data collected from 1986-1990

Dotted Skipper

Hesperia attalus slossonae

Taxonomy & Nomenclature

This and the western subspecies (H.a. attalus) may be separate species.

Identification

A variable species whose most distinctive markings are sometimes absent! It is a large species - almost as big as Leonard‘s Skipper. With luck the hindwing below will bear a constellation of prominent, more or less round, dark-edged, whitish dots. Most likely to be confused with male Crossline Skipper if spots are absent. Dotted usually shows 2 additional white spots on the underside of forewing tip. The species flies in mid-season, which aggravates confusion with several species.

Distribution

Resident sparsely along the Atlantic and Gulf coastal plain and foothills north to New Jersey. According to Schweitzer (pers. comm.), it is uncommon in New Jersey, North Carolina and Florida and generally rare elsewhere. Another subspecies (or perhaps species) ranges from central Kansas south to east Texas. There are no wholly credible New England records supported by specimens.

Status in Massachusetts

This species‘ claim to inclusion on the list of New England butterflies rests on three tenuous Massachusetts records: (1) "several individuals captured on one occasion near Belmont (Middlesex Co.)...by Mr. Roland Thaxter" (Scudder, 1889; no other details are given); (2) "Has been taken in Massachusetts by...Forbes. July." (Farquhar, 1934) and (3) Nantucket, 19 September 1938, C. Kimball (Kimball and Jones, 1943); again, no details are recorded and no specimen now exists in the collection of the MCZ where the Kimball collection now resides (Schweitzer, pers. comm.); possibly a vagrant.

Flight Period in Massachusetts

The September date from Nantucket noted above would be a vagrant from the South. In New Jersey the species flies from mid June to early August (Schweitzer, pers. comm.)

Larval Food Plants

Grasses. Has been associated with Switch Grass (Panicum virgatum), which is common here, especially coastally.

Adult Food Sources

Known to visit a variety of mid-season flowers such as milkweeds, thistles and knapweeds within its normal range. Opler and Krizek (1984) note a preference for the blossoms of Prickly Pear (Opuntia humifusa), which reaches the northern extremity of its eastern North American range on Nantucket.

Habitat

Openings in pine-oak barrens, where its host grasses grow and disturbed marginal areas with poor soils.

Life Cycle

Little has been recorded about the life history of Dotted Skipper. EGG: A Dull white, smooth hemispherical dome with a dense microscupture of tiny punctures. OVIPOSITION: Eggs are laid singly on or near the food plant LARVA: Olive green with a prominent dark head and shelters in a silk bound leaf case at the base of the food plant when it is not feeding. CHRYSALIS: No information. PUPATION: Within leaf roll. OVERWINTERING STAGE: Larva.

Notes

Of Dotted Skipper Scudder (1889) remarked that "there is...no other butterfly of our fauna of which so little is known". Arguably this assertion remains true today.

Account Author

Chris Leahy