Pollinator of the Month: Two Spotted Lady Beetle (Adalia bipunctata)

Adalia bipunctata, commonly known as the two-spotted lady beetle, is a species of beetle in the order Coleoptera. The species name ‘bipunctata’ is composed of the Latin prefix “bi,” meaning two, and “punctatus” meaning spotted. Two-spotted lady beetles are native to North America and are one of the 75 species of lady beetle present in Alberta. This includes introduced, invasive, and native species. The most common introduced species is the seven spotted lady beetle (Coccinella septempunctata). Some other examples of native lady beetles include the eye-spotted lady beetle (Anatis ocellata) and convergent lady beetle (Hippodamia convergens). Increased pressure and competition from introduced species is leading to the range of the two-spotted lady beetle to narrow.

Two-spotted lady beetles can act as pollinators when they seek shelter in flowers for short periods of time, known as accidental pollinators. Adults can overwinter by burrowing in fallen vegetation such as leaves, bark, and sticks. Two-spotted lady beetles can be found inhabiting grasslands, forests, rural, and urban environments. Both adults and larvae prefer to be in shrubs and trees, or any vegetation where there are small insects such as aphids, small insect eggs, and mites to feed on. Their life cycle starts with females laying their bright yellow eggs on the bottom of leaves in locations with sufficient food sources for the larvae. The eggs hatch into larvae which feed until they pupate, and then emerge in their adult form with wings.

Two-spotted lady beetles are 4-5 mm in length and ovoid in shape with 6 legs when at adult size. Their pigmentation and patterning is highly variable. However, the most commonly found form has orange/red elytra (wing cases) with two black spots on the centre of each elytra. The thorax and head are black with two large symmetrical white spots on the thorax, and two smaller symmetrical white spots on the head. The thorax also has two rounded white patches closer to the midline near the base of the elytra. The underside of the lady beetle is also all black.

Posted on August 21, 2023 05:20 PM by jdo77