Adalia decempunctata

(Linnaeus, 1758)

ten-spotted ladybird, ten-spotted lady beetle, 10-spot ladybird

Adalia decempunctata is a small predatory ladybird beetle native to the Palearctic region, recently established in Newfoundland, Canada. The exhibits exceptional color , with individuals showing red, orange, or brown ground coloration and 0–12 (rarely up to 15) dark spots on the . possess chemical defenses based on two alkaloids, adaline and adalinine, with marked in alkaloid composition. The species is an important in both natural and agricultural .

Adalia decempunctata by (c) Barry Walter, some rights reserved (CC BY), uploaded by Barry Walter. Used under a CC-BY license.Adalia decempunctata by (c) Barry Walter, some rights reserved (CC BY), uploaded by Barry Walter. Used under a CC-BY license.Adalia decempunctata by (c) Alexis Tinker-Tsavalas, some rights reserved (CC BY), uploaded by Alexis Tinker-Tsavalas. Used under a CC-BY license.

Pronunciation

How to pronounce Adalia decempunctata: //əˈdeɪ.li.ə ˌdɛ.kɛm.pʌŋkˈteɪ.tə//

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

Identification

Body length 3.5–5 mm. Body glabrous and nearly round. Highly variable coloration: ground color red, orange, or brown; with 0–12 dark spots (rarely to 15), sometimes absent entirely. Pronotum pattern varies: light forms show 5–7 black spots; dark forms have black or brown pronotum with light lateral and borders; mixed forms have black or brown elytra each with 5 orange-red spots. Legs and brown or orange. Distinguished from Adalia bipunctata by coloration of mesepimera, , , antennal club, mouthparts, and legs.

Images

Habitat

Western European broadleaf forests, eastern deciduous forests, Sarmatic mixed forests, forest edges, parks, gardens, wastelands, Eurasian Steppe, and Pannonian Steppe . Found on bushes and deciduous trees, grasses, under bark, in moss on trees, leaf litter, brushwood, coarse woody debris, and alluvial soil.

Distribution

Native Palearctic range: Europe, North Africa, European Russia, the Caucasus, Siberia, Belarus, Ukraine, Moldova, Transcaucasia, and western Asia. Easternmost record Yekaterinburg. Introduced and established in North America: currently limited to the Avalon Peninsula, Newfoundland, Canada.

Seasonality

overwinter in leaf litter and among fallen leaves; active spring through autumn. Emerges in spring to feed on aphids and other small insects.

Diet

Feeds primarily on aphids on trees and bushes. In laboratory studies, successfully reared on Aphis gossypii, Aphis fabae, and of Ephestia kuehniella; developmental rates and vary with prey quality.

Life Cycle

Complete . developmental period 18–33 days depending on food source: shortest on Ephestia kuehniella (18.33 days), longest on Aphis fabae (21.82 days). overwinter. Female highest on Ephestia kuehniella eggs (2405.12 eggs/female in laboratory).

Behavior

Predatory searching focused on colonies. Chemical defense via autogenously produced alkaloids (adaline and adalinine) secreted from leg joints. Aposematic warning coloration. aggregate in leaf litter for .

Ecological Role

in natural and agroecosystems. Part of aposematic warning coloration system with chemical defense to deter natural enemies.

Human Relevance

agent for management in agricultural and horticultural settings. Occasionally mistaken for similar ; larvae sometimes misidentified as pests by novice gardeners.

Similar Taxa

  • Adalia bipunctataSimilar size, shape, and ; distinguished by coloration of mesepimera, , , antennal club, mouthparts, and legs. A. decempunctata shows greater spot number variation (0–12 vs. typically 2 in A. bipunctata).
  • Harmonia axyridisSimilar ladybird beetle and -feeding habit; distinguished by different pronotal pattern and typically more consistent spot patterns.

Sources and further reading