tested. Caterpillars overwinter in the first geographical variants as the Atlantis group. instar and break diapause to complete develop- Treated as single species on the NABA Chasing Greater Fritillaries: ment the following season. Caterpillars bear Checklist, many believe that there are two (or many branching spines, and like other mem- more) species in the group which contains bers of the heliconians and fritillaries tribe of approximately 25 subspecies (see page 17 for brushfoots, lack mid-dorsal spines. However, complete list). Atlantis group populations are The Rise of Atlantis unlike others of their tribe, greater fritillary known from the east coast of the United States caterpillars lack spines on the head. and Canada, west to California, as far north Greater fritillaries are restricted to North as Alaska and south into Arizona and New America and, although absent from the south- Mexico (see maps). W. H. Edwards origi- eastern regions, are found throughout most nally described Atlantis from the northeast in of the United States and Canada. The greater 1862 (type locality now fixed in the Catskills fritillaries, along with very similar fritillaries Mountains, in Hunter, Greene Co., New York). that exist in other temperate parts of the Since that time, numerous additional Atlantis world, may be considered the temperate-zone forms have been described — clear across the counterparts to tropical heliconians. Much continent. Atlantis Fritillaries primarily inhabit of the speciation within the genus probably cool, Canadian life zone habitats; their life came about in the past ten thousand years as history requirements include either the clima- a consequence of the last glacial retreat and tological elements of northern parts of North the climatic readjustments in its wake. Great America or the numerous mountain ranges that Spangled, Aphrodite, Regal, and Atlantis occur in the West. The geographical variants by James C. Dunford Fritillaries occur in the eastern half of North tend to be isolated, and adaptations to local

America (east of the Mississippi River), each environmental conditions have created distinct Perhaps no other butterfly group is comprise the genus Speyeria. Adults are more with distributions or subspecies occurring in forms, especially noticeable in the coloration as perplexing as North America’s or less orange in color (with the exception the west, while Diana Fritillaries are restricted on the underside of the hindwings (see page of female Diana Fritillaries and some female to the eastern United States (in the Appala- 17; also see J. Glassberg’s Eyeing the Greater greater fritillaries. Many lepidopterists Nokomis Fritillaries), with darker wing veins chian and Ozark Mountains). The remaining Fritillaries, American Butterflies 2000 for eye have attempted to shed light on species rela- and spots. Silver, white, or cream hindwing species, Nokomis, Edwards’, Coronis, Zerene, color characteristics in the field. Note: HW tionships in this remarkably variable group. spots are present on the underside of most Callippe, Great Basin Fritillary, Unsilvered, ground color and silvering of spots is vari- Why do we chase after a better understanding species. Adult greater fritillaries frequent Hydaspe, and Mormon Fritillaries occur in the able within some populations. In addition, of Speyeria? Why do they continue to impress open fields, moist meadows, or open wood- western portions of North America and it is the Thomas J. Allen us with a profusion of forms across the land? lands near streams. A number of species are West where the majority of the described sub- Perhaps the sight of a Regal Fritillary visiting restricted to coastal dunes, tallgrass prairies, or species are found. Several species or subspe- your favorite flower or an Atlantis Fritillary montane habitats. Adults are strong fliers and cies have been listed as either federally/state flickering along a forest edge will remind you, are rather long lived (several weeks to months endangered or threatened, i.e., Regal, Diana, we live in Speyeria country! from May-September); all members are uni- Nokomis Fritillaries and subspecies of Zerene For those butterfliers in need of greater voltine (single brooded) each year. Females and Unsilvered Fritillaries. Greater fritillaries fritillary basics, Speyeria are medium to usually lay their eggs rather haphazardly near and the violets upon which their caterpillar large butterflies that are conspicuous North violets rather than carefully placing them on feed are amongst the best indicator organisms American brushfoots. Members of the genus the host plant as most butterflies do; however of native, undisturbed ecological communities. have been examined in great detail in the past in some cases females use their flexible abdo- They are also among the first organisms to be and continue to be a model group for studies men to place eggs directly on the caterpillar eliminated from such communities as a result of evolution, speciation, and conservation. foodplant. Caterpillars feed on several violet of human-caused disturbances. Approximately 14 species and over 100 asso- species (Viola) and under laboratory condi- No other species group of greater fritil- An Atlantis Fritillary caterpillar. Sept. ciated subspecies (or geographical variants) tions will feed on every American species lary is as tangled with different forms and 1994. Spruce Knob, WV. 14 American Butterflies,Summer 2005 15