Coleoptera : Coccinellidae

Coccinellidae

Ladybirds, or ladybugs. In France the Coccinellidae family comprises 100 or so species. They are known as consumers of a wide range of phytophagous species.

Adalia decempunctata : accouplement
coccinelle prépare son vol
Je laisse mes oeufs...
Adalia bipunctata : éclosion

Morphology

The Coccinellidae are terrestrial Coleoptera with elytra entirely covering the abdomen.

  • The size of ladybirds is in the range 1-10 mm
  • abdomen is round or oval, with a thorax (or pronotum) broader than long and members short
  • antennae short, swollen into a club, are inserted most often under the rim of the head.
  • maxillary palps, shorter than the antennae, end in an axe-shaped segment.
  • head is retractable and tucks under the pronotum
  • tarsi consist of four segments (except in Nephus: 3) but the third is so small that it remains hidden by the second.

Biology

Ladybirds overwinter in the adult stage. In spring, as soon as weather conditions are favorable, they mate and each female lays hundreds of eggs close to a food source. Hatching occurs after a period of 4-5 days. The larvae develop in four stages. They all resemble mini "alligator" with three pairs of legs and colored tubercles on the dorsum. Their predatory activity lasts 10-25 days. They then undergo nymphosis. The pupa is immobile, fixed on the foliage and emergence takes place about ten days afterwards. The life span of adults varies from a few weeks to several months depending on the species.

Diet

The Coccinellidae are spread between two subfamilies:

  • The first, the Epilachninae, brings together the four phytophagous species.
  • The second, the Coccinellinae, is much larger and contains species that could play a role in plant protection against certain pests. It comprises: mycophagous species (8% of the species) which consume fungi of the downy or powdery mildew type; predators of Acari and Aleyrodidae (1%); even coccidiphagous forms (10%) which prey on ladybirds; and those that feed on aphids (65%).

Aphid-feeding ladybirds

These are the most numerous in France. They belong to various different tribes:

  • the Coccinellini are generally highly colorful. They measure more than 3 mm long, their body is completely glabrous, the antennae are longer than the head. This tribe includes the following genera: Coccinella, Adalia, Harmonia, Synharmonia, Propylea, Calvia, Myrrha, Mysia, Sospita
  • the Hippodamini also cover strongly colored species whose length exceeds 3 mm: Hippodamia, Adonia, Semiadalia, Aphidecta
  • the Scymnini gather together small-sized species, less than 3 mm, dark in color, where the body is completely covered with fine hairs: Scymnus, Pullus, Sidis,Nephus

Some species :

See also

Le Monnier Y., Livory A.,2003. Une enquête Manche-Nature : Atlas des coccinelles de la Manche. Les dossiers de manche-Nature N°5, 206pp