Insects along the Los Angeles River
Blue Damselfly, Enallagma sp. Commonly called Bluets, these are probably the most common damselfly. Males are usually bright blue and females are blue, grey or brown. Adult length 2.8 -4.0 cm. They range all across California near shallow, fresh water with plentiful vegetation. Bluets usually refrain from flying high above the surface of the water.
Bluets mating. Damselflies are related to dragonflies. Both are predators, living near water and feeding on small flying insects, such as gnats and mosquitoes. Some large dragonflies actually feed on tadpoles and tiny fish. Damselflies are smaller and more frail than their more vigorous cousins. They often perch with their wings pulled back for protection, compared to dragonflies who perch with their stronger wings extended.
Buckeye Butterfly, Junonia coenia. Adult wing expanse is 3.5 - 5.2 cm. Feeds on plantain and plants in the figwort family. Easy to recognize by its distinctive markings. Ranges throughout California. Rare in desert regions.
Female Cabbage Butterfly, Pieris rapae. Introduced from the Old World over 100 years ago. Feeds on cultivated plants and plants in the mustard family. Possibly the most injurious butterfly to the economy. Adult wing span is 3.2 - 5.2 cm.
Skipper Butterfly. Skippers are not true butterflies. They have large heads with stout bodies. Their name is derived from the erratic pattern of their flight compared to the more graceful and gliding flight of butterflies.
Unidentified caterpillar. Moths and butterflies make up the Order Lepidoptera. Butterflies are more well-known with 9 families and over 240 species found in California. However, there are over 3,000 species of moths in the state. Many moth species are probably undiscovered. Most moths are nocturnal while most butterflies are diurnal.
Lady Bug larva. These familiar beetles make up the family Coccinellidae. They are amongst the most recognized and beneficial insects. Both the adults and larvae of most species feed on destructive aphids and other pests.
Lady Bug pupa. There are over 125 species in California. Many were introduced as agricultural predators. In 1888 the Vedalia, Rodolia cardinalis, was brought to California from Australia to control the citrus pest, Cottony-cushion Scale. It became the first insect successfully introduced into another country to control a pest.
Adult Lady Bug, Hippodamia convergens, one of the most common insects in the state. After the success of the introduction of Vedalia, almost 50 more species of lady bugs were brought to California to control agricultural pests. Only four species survived. One is the Mealybug Destroyer which is still raised and released commercially.
Garden spider, which of course is not an insect but an arachnid. But it does feed on insects.
For more information on insects, the L.A. County Museum offers an on-line exhibit, An Inordinate Fondness for Beetles and explore the extensive collection of California Dragonflies and Damselflies. Check out these
Dragonfly and Damselfly Links. Visit the Book of Insect Records from the University of Florida.
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