Noctuidae - Agaristinae



Alypia maccullochii Kirby

Alypia maccullochii Kirby, 1837, in Richardson, Fauna Boreali- Americana, p. 301, pl. 4, fig. 5.

Alypia lorquinii Grote and Robinson, 1868, Trans. Amer. Ent. Soc., 1: 328, pl. 6, fig. 39.

Alypia similis Stretch, 1872, Illustrations of the Zygaenidae and Bombycidae of North America, 1: 14, pl. 1, fig. 5.

Alypia similis var. conjuncta H. Edwards, 1883, Papilio, 3: 34.

Diagnosis: Alypia maccullochii is a disparate member of Alypia and does not resemble any of the other species in the genus. The other species of Alypia have a black forewing with two yellow patchs. The forewing coloration and maculation of maccullochii, in contrast, is more complicated and is much more likely to be confused with that of Agaristinae New Genus 0001 mariposa and Agaristinae New Genus 0001 ridingsii. The forewing is black, the black extending around the entire wing, i.e. the costa, outer margin, and inner margin. The central area of the wing is yellow white with a central y-shaped black bridge stretching between the costa and the inner margin with the two arms of the y-shaped bridge running through the orbicular and reniform marks respectively. The forewing veins within the yellow or yellowish white central area are accented with black. The male forewing has the sound producing structure discussed in the introduction to the genus Alypia. The forewing outer margin fringe is accented with yellow, although the yellow fringe may be lost in rubbed specimens. The ventral forewing surface recapitulates the dorsal surface. The hindwing is also black around the inner and outer margins with a central yellow or yellowish white region. The central light region is crossed by a large black band through the discal dot from the inner margin to near the costal margin but ending on the radial vein. The veins in the light area are accented with black. The ventral surface is identical to the dorsal surface. The palpi are black-brown without any of the yellow scales found in octomaculata, wittfeldti, or langtoni. A band of yellow scales is present along the outer margin of the eye, but yellow scales are absent from the outer margins of the frons. The frontal process is large and wide, much wider than in the other species of the genus. Large tufts of orange scales are present on the prothoracic and mesothoracic tibiae (as in all members of the genus Alypia). Black tufts, lines, or scales are completely absent from the dorsal abdominal surface. The male genitalia of maccullochii differ from those of the other four species in Alypia in the placement of the clasper. The apex of the clasper reaches or exceeds the outer margin of the valve, but never reaches the outer margin in the other four species. The juxta is divided into two halves by a distinct clear, membrance central zone. This zone is absent, or not clearly present in the other four species of Alypia. Basal abdominal hair pencils are absent in maccullochii, but present in octomaculata. The female genitalia are very similar to those of octomaculata and includes the overhang of the eighth abdominal segment typical of octomaculata. However the two descending arms of the ostium are more divergent and not as parallel as in octomaculata.
Wing length: (males) mean = 11.93 mm, standard deviation = 0.51 mm, n = 10; (females) mean = 13.27 mm, standard deviation = 0.98 mm, n = 10.

The male forewing of maccullochii contains a well developed sound producing structure discussed in more detail in the introduction to the genus. The only reference I have found to sound production by this species, however, is in Stretch (1872). Stretch makes a one sentence reference to observations by Henry Edwards of the male making a clicking noise "when in pursuit of the female". I interpret this sentence to mean that the male makes a clicking noise while flying. The ability to make this sound make be under volutary control (as in Hecatesia) and is probably part of the courting ritual.

Distribution (See Map on Left): Alypia maccullochii has a wide distribution in northern North America and the northwestern United States. This species occurs either in boreal habitats or the higher elevations of mountains in the more southerly parts of its range. The species occurs as far east and the central and northern parts of Ontario, westward across most of boreal Canada and northward through the Northwest Territories, the Yukon, and Alaska. The species has been best collected in northwestern United States, British Columbia, and western Alberta. The species is common in the mountains regions of Montana, Wyoming, Colorado, Idaho, Washington, Oregon, and northern California. The species occurs as far east as the Black hills of South Dakota. Males are slightly smaller than females. The color of the clear areas of the forewing and hindwing is slightly variable. The color is usually yellow, but it sometimes fades to yellow white. A few males from the more northern localities have these clear areas nearly white. Females are more consistent in this yellow coloration than are males.

Adults fly in June and July.

Identification Quality: Excellent

Larva: The larva is very similar to that of langtoni. The body is white with yellowish shades on the lateral sides of the body. The pinacula and strong and black and each is surrounded by an ovate black pigmented region. The setae are particularly long and well developed. The dorsal line is double and reasonably continuous. An series of irregular lines and dashes occupies the lateral parts of the body dorsal and ventral to the spiracles. An wide, irregular double black line runs along the upper ventral region and enclosing the pinaculae of setae L3. The dorsal part of the proleg is black and its apex has a black spot. An orange blotch is found ventral to setae D1 and D2 on abdominal segment 8. The head is white and covered with large, black, spots. The larva is very similar to that of langtoni. The larva of langtoni, however, has orange patches on every abdominal segment, not just on segment 8. Alypia langtoni and Alypia octomaculata both have a large white patch stretching between seta L1 of abdominal segment 7 and L2 of abdominal segment 8. This white patch is absent in maccullochii. The lateral maculation of maccullochii tends to run in a cephalad-caudal direction, but in langtoni and octomaculata the lines run from dorsal to ventral. The double dorsal line of maccullochii is absent in langtoni, although some specimens of langtoni have a diffuse brown-black dorsal line.

Foodplants: The larva has been described by Dyar (1903) and Crumb (1956). Both descriptions are based on the same series of specimens reared by Dyar and recorded from Epilobium angustifolium (Onagraceae).


Alypia maccullochii

Alypia maccullochii is most likely to be mistaken for Agaristinae New Genus 0001 ridingsii. The two species are easily separated, however. First the eyes of ridingsii are hairy, but those of maccullochii are not. Yellow-orange scales are present on both the prothoracic and mesothoracic tibia in maccullochii but only on the mesothorac tibia of ridingsii. A row of yellow-white scales is present along the outer margin of the eye of maccullochii, but these scales are black in ridingsii. Finally the male forewing of maccullochii has the sound producing organ discussed in the generic description, but no such organ is present in the male forewing of ridingsii. Both the male and female genitalia of the two species are abundantly distinct as illustrated in the appropriate figures.

Similar Species

Agaristinae New Genus 0001 ridingsii