Callippe Silverspot Butterfly (Lepidoptera: Nymphalidae)
Scientific Name: Speyeria callippe callippe
Federal Status: Endangered
State Status: None
The Callippe Silverspot Butterfly is a member of the Nymphalidae,
or brush-footed butterflies. The Callippe Silverspot has a wingspan of approximately
4.5 cm. As illustrated above, members of this species are mainly orange, tan and
brown above. The name "silverspot" refers to silvery patches of scales on the undersides
of the wings. Historically this butterfly inhabited grasslands ranging over much
of the northern San Francisco Bay region. The type locality, or site from which
the subspecies was first recognized, is the city of San Francisco. On the San Francisco
peninsula, this butterfly is now only known from San Bruno Mountain (approximately10
miles south of San Francisco). In the East Bay, it was known from Richmond in the
north to the Castro Valley in Alameda County. The only remaining population of this
butterfly in Alameda County occurs in an undisclosed city park.
The Callippe Silverspot begins its life in early summer when the
eggs hatch. The first instar larvae eat their egg shells before going into diapause
(a period of inactivity and reduced metabolism). Following the winter rains, the
larvae emerge to begin feeding on their host plant, a Violet (Viola pedunculata).
Following 2-3 months of feeding and 4 molts, the larvae make a pupation chamber
from leaves and silk and then molt into the pupal stage. The pupal stage lasts for
only about 2 weeks, at which point the adult butterfly emerges. Adults live for
approximately 3 weeks during which time they feed and mate. The main source of sustenance
for the adult butterflies is floral nectar. After mating the females seek oviposit
(lay eggs) on or near Viola plants (which, as annuals, will be mostly wilted by
this time).
The causes of the Callippe Silverspot's decline are fairly clear.
The vast majority of potential butterfly habitat lies under the cities of San Francisco,
Oakland, and Berkeley. What open areas there are within this butterflies range are
dominated by introduced plant species. Many of these areas are also grazed by cattle,
mined, or subject to heavy recreational use. The Alameda County population is particularly
small and vulnerable. The San Bruno Mountain population occurs on land that, although
private, is largely protected from development. This area is also being managed
for the conservation of several additional endangered species, including the
San Bruno
Elfin and the
Bay Checkerspot.
Source: http://essig.berkeley.edu/endins/callippe.htm