|scientific name Podisus placidus |
Evans (1983) reports this species in old-field habitats, as well as in both mixed and deciduous forests.
Adults appear in mid-April and are abundant until late-August, but can be found as late as October (Evans 1983; Oetting and Yonke 1971).
This species is lighter in coloration in comparison to other Podisus species. The dull-yellow mottling of the cuticle is much more prominent. The shape is somewhat quadrangular with the posterior of the dorsum nearly triangular shaped. The pronotal margins are straight-sided with broad, rounded projections on either side. This characteristic sets it apart from other Podisus species, as well as Apateticus bracteatus since these species generally have concave pronotal margins. The connexivum are nearly concealed under the hemelytra and the portions that are exposed have black spots along the margins of each abdominal segment. This is a relatively small species with a length of 7.5 to 9 mm (Blatchley 1926).
There appears to be some discrepancy concerning the number of generations that occur in a season. McPherson (1982) indicates that the occurrence of both univoltine and bivoltine populations may exist within northeastern N.A. Adults begin mating in early May shortly after emerging from hibernation. Females will deposit their eggs on the undersides of leaf surfaces an average of 1 egg mass per 5 days until the she dies (Oetting and Yonke 1971). Females can lay upwards of 300 eggs under laboratory settings (De Clercq 2000). Eggs take about 6 days to hatch and require temperatures of between 20° C to 25° C (De Clercq 2000; Oetting and Yonke 1971). Maturation to adult takes between 25 to 30 days (De Clercq 2000).
This species has been implemented in several failed biological control attempts in Europe (De Clercq 2000).
This species is a polyphagous predator that feeds primarily on the larvae of Lepidoptera and Symphyta (Hymenoptera) as adults. Evans (1983) reports significant numbers feeding on forest-tent caterpillar, Malacosoma americanum, colonies in Ithaca, New York, within the tents, as opposed to on the tents or in the areas surrounding them. It has been reported that they feed on plant juices as first instar nymphs (McPherson 1982).
In North America, this species ranges from British Columbia to Quebec, Canada (Maw et al. 2000), and as far South as Arkansas, though these southerly records are generally restricted to eastern states (Henry and Froeschner 1988). It is not known whether it's distribution extends beyond North America. No specimens of this species have been collected in Alberta.
Oetting and Yonke (1971) report a detailed description of the egg and nymphal stages of this species. Here they report that nymphal instars can be effectively identified based on the width of the head and pronotum.
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