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Spined Assassin Bugs – Sinea diadema

Spined Assassin Bugs   Latin Name: Sinea diadema Common Name: Spined Assassin Bugs, Spiny Assassin Bugs, Common Brown Assassin Bug, Crowned Assassin Bug. Appearance: Spined assassin bugs are 12-16 mm long bugs and have a long head and a short three-segmented beak. The head has a pair of long slender antennae that have four segments. S. diadema is a unicolored bug having a dull red or dark brown color. They have front legs slightly thicker and covered with small spines. The wings don’t cover the whole body due to the wider abdomen at the center. Host Plants or Food: Bugs, Caterpillars, Bees, Flies, Beetles, Leafhoppers. Territory: Throughout the United States. Mode of Damage: They prey on different plant pests, so they are considered Beneficial Garden Insect Habits and Life History: Spined assassin bugs are usually found in grasslands, agricultural fields, gardens, meadows, and weedy fields. Female spined assassin bug lays eggs on the leaf surface or under loose soil. The eggs are cylindrical in shape and have a brown color. They are covered with a red-brown secretion. After egg hatching, nymphs develop through relatively five larger instars that resemble adults but don’t have wings. Nymphs hibernate during instars’ development, and the last instar develops into an adult and comes out as a reproductive spined assassin bug.