Note White Rings on Antennal Segments
Alypia langtoni Couper
Diagnosis: Alypia langtoni is the northern and montane version of octomaculata occurring in the Canadian Forest and Boreal regions of Canada and the northeastern United States and the montane forests of the western United States. The species is the only explicitly sexually dimorphic species of Alypia. The female is very distinctive and cannot be confused with octomaculata, but the male is very similar to that of octomaculata and easy to misidentify in localities both species are likely to inhabit. The antennae of langtoni have white rings around the antennal segments (see figure on left). The male and female forewing are both black with two yellow-white patches. The yellow-white patches are slightly larger and more irregular in the female than the male. The male hindwing is black with a white basal region separated by a black bridge running through the discal area from a small, round other white patch. The basal white patch is streaked with black on the cubital and anal veins but most strongly on the anal vein. The ventral hindwing pattern recapitulates the dorsal surface. The female hindwing is black with a single yellow patch in the distal part of the discal cell, although some rare specimens (particularly from California) have a small basal yellow patch as well. Wing length: (males) mean = 13.04 mm, standard deviation = 0.64 mm, n = 10; (females) mean = 13.81 mm, standard deviation = 0.76 mm, n = 10.
Distribution (See Map on Left): Alypia langtoni
has a wide distribution in northern North America. The species occurs
throughout most of Canada from the Canadian Zone forests of southern Canada
to the boreal forest and tundra regions of the Northwest Territories,
the Yukon, and Alaska. Alypia langtoni occurs in the eastern
United States in northern and central Maine, northern New Hampshire, northern
Vermont, and the Adirondack Mountains of upstate New York. The species
has been collected in northern Michigan and in Minnesota. This species
has a wide distribution in the mountains of the western United States.
The moth has been collected from the Canadian border east to western Montana
and western South Dakota and south as far as the White Mountains of central
Arizona. The distribution of the species in California reaches as far
south as Santa Cruz County. Throughout most of its range the species is
not particularly variable. The size of the white patches in the male hindwing
is variable and in some inviduals the patches can be very small. In a
few females a small yellow basal patch is present, sometimes more strongly
developed ventrally than dorsally. A few old specimens from California
have well developed basal yellow spot in addition to regular distal yellow
patch. These specimens were the basis of the name Alypia dipsaci
Grote and Robinson 1868. Scattered rare male specimens of langtoni
from Colorado, California, and Alaska have the forewing patchs nearly
white rather than yellow. The white color may be intrinsic, but in many
specimens faded specimens tend toward white. This type of specimen was
responsible for the name Alypia brannani Stretch 1872.
Identification Quality: Excellent
Larva: The larva is similar to that of octomaculata.
The ground color is white with extensive black-brown markings. The setae
are well developed and the pinaculae are large and black-brown. A large
black-brown patch is present in the dorsal region of each abdominal segment.
This large patch includes the pairs of setae D1 and D2. The black of this
large patch runs downward into the region of the spiracle on either side
of the abdomen. This large dorsal patch is followed on the caudal half
of each segment by a much smaller triangular patch. This small triangular
patch usually has a small yellow-white central area. The spiracle of each
abdominal segment is surrounded by an irregular orange patch. This patch
is enclosed on both sides by irregular black-brown lines running down
from the large black-brown patch on the dorsal surface of each segment.
Irregular black-brown patches and lines are found both caudal and cephalad
to the central region of the segment. A series of yellow-white patches
forms an irregular subspiracular line. A large white patch stretches from
seta L1 on abdominal segment 7 to L2 on abdominal segment 8. This same
patch is found in octomaculata. The ventral surface of the abdomen
is black brown with an series of white patches forming an irregular ventral
line. The head is white with black spots on the setae insertions and these
black spots are interspersed with black freckles.
Foodplants: The larva has been described by Crumb (1956) who recorded Epilobium spp. (Onagraceae) (fireweed) as foodplants. Reared adults in the USNM are all listed as reared from either fireweed or "Epilobium".
The female of langtoni is easily separated from that of octomaculata by the presence of a single yellow-white patch in the hindwing. The female hindwing of octomaculata is basically the same as that of the male with a basal white patch separated by a black bridge from a smaller white patch in the outer half of the discal cell. The male of langtoni, however, can be difficult to distinguish from a male octomaculata. The following characters, however, will almost always separate the two species. The best character separating males of the two species is the presence of white rings around each of the basal antennal segments in langtoni and their absence in octomaculata. The character can sometimes be seen with the naked eye, but it is best to examine specimens under the microscope or with a hand lens. The ventral surface of the basal antennal segments of octomaculata may have white scales, but these white scales do not form white rings and are not visible on the dorsal surface of the antenna. The distal end of the second palpal segment has a ring of yellow hair-like scales in octomaculata. Yellow hair-like scales are present in langtoni, but are much less common and usually restricted to the inner side of the second and third segments. Both langtoni and octomaculata have a rows of yellow scales on the outer margins of the front of the head. This row of yellow hair-like scales is not as strong in langtoni as in octomaculata. In langtoni this row of yellow hair-like scales is two to three times longer than wide and the lower end of the row ends near the top of the frontal process. This row is four or five times longer than wide in octomaculata and the lower end usually curves slightly around the lower end of the frontal process. Wing maculation characters for separating males of langtoni and octomaculata are useful but less reliable. The two yellow forewing patches are usually (but not always) smaller in langtoni than octomaculata. The basal white hindwing patch of langtoni is typically smaller and more heavily streaked with black than it is in octomaculata. The male genitalia of langtoni and octomaculata are not significantly different. However the female genitalia are readily distinguishable. The caudal margins of the ventral surface of the eighth abdominal segment project over the ostial region and form a definite caudal rim in octomaculata (and wittfeldii). The caudal margins in langtoni, in contrast, do not project and do not form a definite rim in the ostial region in langtoni.
Alypia octomaculata male
Alypia octomaculata female