Clover and Coreids

While pretty purple Wedgeleaf Prairie Clovers were busy overspreading the warm dunes of coastal Texas, their genus-mate, Golden Prairie Clover (Dalea aurea) was standing tall in the gravelly loam of the Texas hill country.

Spreading as far north as South Dakota and a bit west into Arizona and Colorado, this warm season perennial — a member of the pea family —  prefers the sandy soils of mesas, roadsides, and shortgrass prairies. Both livestock and white-tailed deer find Golden Prairie Clover to their liking, which helps to explain why it’s often seen along roadsides, or on land free of cattle.

When I found my first group of one to two foot tall bloom stalks, they were growing alongside Texas 187, north of the Lost Maples Natural Area. The two closeups of flowers were taken on Gillespie County’s Willow City loop, where they’d established themselves in a roadside patch of gravel near a ranch gate.

When in bloom, a spiral of yellow, pea-like flowers encircles a cone-like spike; the same silky, gray hairs that cover the leaves and stem are obvious on the spike.

The flower is especially attractive to a variety of bees, but no bees hovered around these blooms. Instead, a crab spider lurked beneath a petal of the flower pictured below, and a nymph of the common cactus bug, Chelinidea vittiger, had found its way onto the stem.

Cactus bugs, also known as Cactus Coreids, are shield-shaped insects with piercing mouth parts. While adults have wings, the nymphs are wingless; both feed in groups on prickly pear cactus.

The first indications of feeding are light, circular spots on the pads which show that the insects have been at work for some time. With continued feeding, the spots become larger and coalesce, and the entire pad becomes yellowish and pitted.

Secondary invasion by fungi sometimes causes large, black spots. When the infected areas drop out, a nearly circular opening through the joint may appear, or an entire pad may drop off.

After progressing through several stages, the still-wingless nymph becomes increasingly attractive. The brown, leathery appearance of this latter stage makes the insect easily recognizable, even when it leaves its preferred prickly pear to explore the world of a Golden Dalea.


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