Aclypea opaca

(Linnaeus, 1758)

dark carrion beetle, beet carrion beetle

Aclypea opaca is a carrion beetle in the Silphidae, commonly known as the dark carrion beetle or beet carrion beetle. The is native to northern and central Europe and has been introduced to North America, where it occurs in Alaska and the Northwest Territories. Unlike many carrion beetles, species in the Aclypea are phytophagous, feeding on living plant material rather than carrion.

Aclypea opaca by (c) Tina Ellegaard Poulsen, some rights reserved (CC BY), uploaded by Tina Ellegaard Poulsen. Used under a CC-BY license.

Aclypea opaca by alaskanent. Used under a CC BY-SA 2.0 license.

F6-9 Aclypea opaca (Linnaeus, 1758) (3) by NHM Beetles and Bugs. Used under a CC BY 2.0 license.

Pronunciation

How to pronounce Aclypea opaca: //əˈklaɪpiə oʊˈpɑːkə//

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Aclypea opaca can be distinguished from other carrion beetles by the diagnostic cleft —a deep notch in the "upper lip" just behind the . It can be separated from the only other North American in the , A. bituberosa (Western Spinach Carrion Beetle), by geographic range: A. opaca is restricted to Alaska and the Northwest Territories, while A. bituberosa occurs from British Columbia and Washington east to Nebraska and Manitoba. A. bituberosa also possesses raised near the rear of each , which are absent in A. opaca.

Images

Distribution

Native to northern and central Europe; introduced to North America where it occurs in Alaska, the Northwest Territories, and the Yukon. The has also been recorded in the Azores as an introduction. In Europe, its range extends from Scandinavia southward, with records from Russia (European part, Siberia, Far East), Armenia, Georgia, Iran, Uzbekistan, Kyrgyzstan, Kazakhstan, and Mongolia. In China, it is known from Xinjiang and Xizang.

Diet

Phytophagous. and larvae feed on living plant material, including spinach, beets, wheat, radish, rhubarb, potato, lettuce, cabbage, turnip, rapeseed, pumpkin, squash, and lamb's quarters. Beets and spinach suffer the most damage in May.

Host Associations

Spinacia oleracea - pestoccasional pest; one of the most damaged crops
Beta vulgaris - pestsuffers the most damage in May
Triticum aestivum - food plant
Raphanus sativus - food plant
Rheum rhabarbarum - food plant
Solanum tuberosum - food plant
Lactuca sativa - food plant
Brassica oleracea - food plant
Brassica rapa - food plant
Brassica napus - food plant
Cucurbita pepo - food plant
Chenopodium album - food plantlamb's quarters, native
Iva axillaris - food plantpovertyweed, native

Life Cycle

emerge early in spring. Females lay in soil, with larvae hatching in approximately one week. Larvae feed during the day on young leaves and shoots, hiding in soil at night. Three instars occur: the first two each last about five days, the third lasts approximately fifteen days. Mature larvae are black, 11–15 mm long. occurs 1–2 inches deep in soil, with adults emerging in about three weeks. One per year; adults overwinter.

Behavior

Larvae are feeders on above-ground plant parts, becoming nocturnally subterranean for shelter. are active from March through November.

Human Relevance

Considered an occasional agricultural pest, particularly of spinach and beets. Damage is most severe in May. The is not native to North America and was introduced accidentally.

Similar Taxa

Aclypea bituberosaOnly other North American in ; distinguished by raised on and much broader geographic range (Pacific Northwest to Great Plains)
Other SilphidaeMost carrion beetles are saprophagous on carrion; Aclypea are phytophagous, a notable ecological divergence within the

More Details

Taxonomic placement

Despite the "carrion beetle," in the Aclypea are unusual among Silphidae in being phytophagous rather than carrion-feeding. This represents a distinct ecological shift within the .

Introduction history

The appears to have been introduced accidentally to North America from Europe, with established in Alaska and the Northwest Territories. It is not known to have spread as extensively as some other introduced beetles.