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The relationships of Afrotropical tiger moths remain relatively poorly analyzed (see Goodger & Watson 1995), despite some noticeable new generic descriptions (see Goodger & Watson 1995, Dubatolov 2006a, 2006b, 2009, 2009, Dubatolov & Haynes 2008). While studying series of tiger moths from the Natural History Museum and Manchester Museum, some specimens of “ Diacrisia ” epicaste Fawcett, 1915 (synonyms include “ Spilosoma ” occidentalis Bartel, 1903 and “ Amsacta ” melanogastra Holland, 1897) were found to have genitalia unlike any known Spilosomina genus, and are transferred to a newly described genus as follows.

The ground-dwelling woolly bear caterpillar Diacrisia virginica occupies a habitat characterized by low-lying forbs, grasses, and sedges where it feeds on more than 100 species of plants. The short effective range of its visual and olfactory senses restricts to 1 cm or less the distance from which it can recognize plants. Caterpillars meander randomly and blunder into food plants. Because of the dense and complex vegetational texture of the habitat, the random locomotion in the field, and the omnivorous diet of the caterpillars, only a small proportion of time need be spent wandering (2%). More than 90% of the time is devoted to inactivity which represents postprandial and trail resting. Meal size is regulated by state of deprivation and is modified by the position of the plant in the hierarchy of acceptability. With increasing deprivation larvae become less finicky and therefore seldom experience acute starvation. The effectiveness of plants in sustaining survival and optimal growth of caterpillars is only grossly correlated with acceptability. The field behavior of D. virginica seems to be well described by the thermostatic model of feeding which predicts time budgeting for animals as a function of physiological and ecological parameters.

Effects of stand density and late-season defoliation by Mexican bean beetles, Epilachna varivestis Mulsant, on three yield components of beans were estimated from field studies conducted during 1983 and 1984 in four fields of pinto beans in northeastern Colorado. Number of beans per plant, mean weight of a bean, and mean weight of beans per plant were calculated for 100 samples per field, and regressed against three independent variables: plant density, percentage of defoliation, and density × defoliation interaction. Results of the analyses showed that plant density negatively affected number of beans per plant and weight of beans per plant, but not average weight of a bean. Responses were not linear; slope decreased at higher densities. Defoliation negatively affected all three yield variables. Average weight of a bean was linearly related to defoliation. Number of beans per plant and weight of beans per plant showed linear responses above a threshold level of defoliation. A piecewise regression model indicated that yields were not affected by defoliation until levels reached approximately 19% foliage loss. Laboratory consumption studies were conducted to determine age-specific damage potential for Mexican bean beetles and two occasional defoliators of pinto beans, saltmarsh caterpillars, Estigmene acrea (Drury), and yellow woollybears, Spilosoma virginica (F.). Insect consumption potentials and field studies of yield responses to defoliation were used to estimate threshold densities.

A BL trap was operated in 1970 in Craighead County, Arkansas, and results of catches were used as a basis for construction of curves to illustrate fluctuation and seasonal trend for 12 species of moths. The forage looper, Caenurgina crechtea (Cramer), was collected in the largest numbers and was followed by the claybacked cutworm, Agrotis gladiaria (Morrison); corn earworm, Heliothis zea (Boddie); dingy cutworm, Feltia subgothica (Haworth); armyworm, Pseudaletia unipuncta (Haworth); bristly cutworm, Lacinipolia renigera (Stephens); yellow woollybear, Diacrisia virginica (F.); variegated cutworm, Peridroma saucia (Hubner); black cutworm, A. ipsilon (Hufnagel); saltmarsh caterpillar, Estigmene acrea (Drury); cotton leafworm, Alabama argillacea (Hubner); and granulate cutworm, F. subterranea (F.). The claybacked cutworm, dingy cutworm, and cotton leafworm were collected after September 10, with distinct peaks in October. Most specimens of the variegated cutworm and bristly cutworm were trapped by late June. The armyworm, yellow woollybear, forage looper, black cutworm, and saltmarsh caterpillar were relatively active throughout the period from April 3 to November 13. The trapped male:female ratios were: corn earworm 8:5, saltmarsh caterpillar 4:1, and armyworm 1:1.

Laboratory applications of 4'-(3,3-dimethyl-l-triazeno) acetanilide (American Cyanamid CL-24055) to cotton plants limited leaf feeding and reduced the larval weights of the bollworm, Heliothis zea (Boddie); tobacco budworm, H. virescens (F.); cabbage looper, Trichoplusia ni (Hubner); yellow woollybear, Diacrisia virginica (F.); and cotton leafworm, Alabama argillacea (Hubner). Feeding damage by the cabbage looper was reduced 90% when larvae were placed on leaves 2 hr after 24 hours. Injection or topical applications of CL-24055 to bollworm larvae did not reduce larval feeding as much as foliage applications. In field-cage studies a 58% reduction occurred in populations of bollworm larvae after treatment with CL-24055. Also, in a field test with CL-24055, a 22% reduction occurred in squares and bolls damaged by Heliothis spp. Tobacco budworm larvae fed leaves treated with CL-24055 weighed less, whether or not the labial palpi were removed. The following materials caused no (A1%) reduction in tobacco budworm and cabbage looper larval feeding and weight: alpha- (3-phenylpropyl) piperonyl alcohol; phenacyl thiocyanate; N-sec- butyl- p -toluamide; p -(1,1,3,3-teracnetgyt-butyl) phenyl propionate; octyl m -toluate;4 (or5)-chloro- N-N -diethy 1-2-methylcyclohexanecarboxamide; N ,2,2-trimethy1-4',5'-(methylenedioxy)-3 (2-methylpropenyl)-2'-propylcyclopropanecarboxanilide; N -butylsuccinimide; 2-methyoxyethyl 4(or 5)-chloro-2-methylcyclohexanecarboxylate; calamus oil distillate fractions; imidazole; and the plant pigment quercetin (3,3', 4'5,7-pentahydroxyffavone).

Curves showing the hourly and seasonal catches in traps equipped with black light lamps are given for 6 species of North Carolina insect pests: the army worm, Pseudaletia unipuncta (Haworth); the yellow-striped army worm, Prodenia ornithogalli Guenee; the black cutworm, Agrotis ipsilon (Hufnagel); the grape leaf skeletonizer, Harrisina americana (Guerin-Meneville); the yellow woollybear, Diacrisia virginica (F.); and the European corn borer, Ostrinia nubilalis (Hubner).