Agaristinae New Genus 1 ridingsii Grote
Alypia ridingsii Grote, 1865, Proc. Ent. Soc. Philad., 3: 521, pl. 5, fig. 1.
Diagnosis: Agaristinae New Genus 1 ridingsii is a slightly smaller version of mariposa. The length of the forewing from its base to its apex is approximately 16.5 mm in mariposa, but only about 14 mm in ridingsii. The superficial appearance of ridingsii is close to that of mariposa. The most distinctive feature separating the two species is the black accenting on the forewing veins between the reniform mark and the postmedial line is ridingsii. These veins are not accented with black in mariposa. The coronal spines of the male genitalia of mariposa are restricted to the apex of the valve, but in ridingsii the coronal spines are very dense and stretch along the outer margin of the valve almost all the way to the position of the clasper. The clasper of ridingsii has two tooth-like projections on its inner surface. These tooth-like projections are absent in mariposa. The ovipositor lobes of mariposa are unmodified, but each ovipositor lobe of ridingsii is shaped like a slightly convoluted mushroom cap. The outer ring of the ostium characteristic of so may genera of the Agaristinae is absent in mariposa by represented by a small reminant in ridingsii. Wing length: mean = 13.80 mm, standard deviation = 0.43 mm, n = 10.
Distribution: This species has a much wider distribution
than mariposa, occurring throughout much of the western United
States and southern British Columbia. Agaristinae New Genus 0001 ridingsii
occurs as far east as the eastern edge of the Rocky Mountains in
Colorado, and has been collected in Arizona and Utah. The species occurs
commonly throughout all of California and northward into Oregon, Idaho,
Washington, and into southern British Columbia. Little or no variability
exits in this species.
Identification Quality: Excellent
Larva: The larva has been described and figured by Comstock and Dammers (1942). Their description is repeated below.
The mature larvae cut holes in reeds, cork, and yucca to pupate in, and the opening of the cavity is covered with chewed fragments. The larva pupated in late May, the adult emerging the following June.
Foodplants: Comstock and Dammers (1942) recorded the following foodplants: "Oenothera" bistorta (currently Camissonia bistorta, "Eulobus" californicus (currently Camissonia californica, "Oenothera" dentata (currently (Camissonia dentata, and Clarkia rhomboidea, all members of the Onagraceae. The larvae were recorded as feeding on the seed pods.
Agaristinae New Genus 1 ridingsii
Agaristinae New Genus 1 ridingsii might be confused with Alypia maccullochii. Both species have the veins following the reniform mark of the forewing accented with black. The absence of white scales along the outer margin of the eye and the lack of orange scales on the prothoracic leg will immediately identify ridingsii. In addition orbicular and reniform marks of maccullochii form a v-shaped structure with its apex on the inner margin of the forewing. The orbicular and reniform marks fuse with the trapezoidal inner margin patch to form a square structure in ridingsii and mariposa.
The differences between mariposa and ridingsii are listed in the species diagnostic section above.
Agaristinae New Genus 1 mariposa