Mating Red Shouldered Bugs

Subject: Bug Identification, Philadelphia
Location: Philadelphia, PA, (Aspen & 23rd Sts)
August 31, 2016 8:13 am
Hi Bugman,
These bugs are all over the ground under trees and shrubs in our Philadelphia neighborhood. None of us have ever noticed them before but now they’re profuse under the shrubbery and trees surrounding a block-size parking lot. They look like they’re mating (picture 1) but I’ve also seen signles. And there are tiny versions (picutre 2).
Thanks for solving our mystery. We’re all stumped!
Merrill Mason
Fairmount neighborhood, Philadelphia
Photos taken at 6pm, August 30, 2016
Signature: Merrill Mason

Mating Red Shouldered Bugs
Mating Red Shouldered Bugs

Dear Merrill,
Your images are an excellent documentation of both adult mating Red Shouldered Bugs,
Jadera haematoloma, and an immature, wingless nymph.  This is a species known for gathering in large aggregations.  According to BugGuide:  “Adults and larvae tend to feed in groups, and favor developing seeds and fruits of their favored hosts, but will also suck sap from foliage, flowers, buds, or oozing stems. They feed on a variety of plants primarily in and related to the family Sapindaceae. Favorites include Balloonvine (Cardiospermum species) and Goldenrain Tree (Koelreuteria sp.), both in Sapindaceae, and they regularly use Soapberry (Sapindus sp.; Sapindaceae) and Maple/Boxelder (Acer sp.; Aceraceae). Additionally, reported on a variety of other plants, especially feeding on fruit, including Chinaberry (Melia azedarach; Meliaceae), Fig (Ficus spp.; Moraceae), Althaea (Malvaceae), Plum, Cherry, & Peach (Prunus sp.; Rosaceae), Apple (Malus sp.; Rosaceae), Grape (Vitis sp.; Vitaceae), Ash (Fraxinus sp.; Oleaceae), etc. Adults sometimes gather around human food leftovers and other smashed insects to feed as well.”  Because of the preferred host tree, they are sometimes called Goldenrain Tree Bugs.

Red Shouldered Bug Nymph
Red Shouldered Bug Nymph

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