However, recent research by Dr Ross Galbraith and Dr Peter Cameron found no evidence for the collection of the eleven-spotted ladybird in England and its deliberate release in New Zealand, and documented the process of cumulative misreporting that created the record. This would make it the earliest biological control agent to be deliberately released into New Zealand for the control of insect pests. There are also reports that this ladybird was obtained from the Entomological Society of London and were released into New Zealand in 1874 by the Canterbury Acclimatization Society. One early New Zealand Entomologist, Dr David Miller, reported the supposed 1874 introduction (release) but also commented that it could have arrived and become established as early as 1837. It was long believed that eleven-spotted ladybird was deliberately released in New Zealand. Scientific Nameīrachycaudus helichrysi (Kaltenbach, 1843) The reliability score shows the quality of evidence for the host association (0-10, 10=high quality). Table: Prey of Eleven-spotted ladybird, Coccinella undecimpunctata (Coleoptera: Coccinellidae), from Plant-SyNZ database (). Fan, 2001Ĭoccinella undecimpunctata Linnaeus, 1758 The reliability index shows the quality of evidence for the host association (0-10, 10=high quality). Table: Natural enemies of Eleven-spotted ladybird, Coccinella undecimpunctata (Coleoptera: Coccinellidae), from Plant-SyNZ database (). The still live, but very weak adult ladybird is still stuck on top of the cocoon. The adult parasitoid, after hatching form the pupa and its skin hardening, chews its way out of the cocoon. The parasitoid larva pupates in the cocoon. When it is fully grown it exit on the underside of the ladybird and spins a cocoon with the adult ladybird attached on top. The parasitoid larva develops in the live ladybird. The adult female parasitoid lays an egg in the adult ladybird. The parasitoid attacks other species of ladybird. This wasp may cause heavy parasitism in late winter and up to 85% parasitism from mid-summer onwards. The insect pathogenic fungus, Beauvaria bassiana (Balsamo) Vuillemin, may kill 56-90% of overwintering adult ladybirds in wet winters.Īdult ladybirds may be parasitized by Dinocampus coccinellae (Shrank 1802) (Hymenoptera: Braconidae). They may also be eaten by predatory insects including their own species. They are a prominent part of the diet of older sparrow nestlings. In New Zealand, adult and larval eleven-spotted ladybirds are eaten by several bird species. Legs do not appear to be used for holding food. The jaws are the primarily structures used for holding and chewing the prey. The adult and larval ladybirds eat aphids and other insects. There are at least two generations per year the first coincides with the spring flush of plant growth and high aphid populations. Larvae may be present from late September onwards. In spring (August onwards), overwintering females feed and lay eggs. The same overwintering sites may be used every year. (white cedar), kowhai, ( Sophora tetraptera), among needles on lateral shoots of Pinus radiata, under loose bark, and in cracks in old wooden fence posts. In Canterbury, they hibernate from April to September on Thuja orientalis L. The length of time of each life stage depends on temperature, being shorter at higher temperatures.Īdult eleven-spotted ladybirds overwinter, often sheltering in large groups. If disturbed, the pupa can wag up and down. The pupa remains attached to the plant by its hind end, which is usually surrounded by the moulted larval skin. When the fourth larval instar is fully grown, it attaches itself to a sheltered place on a plant and moults into a pupa. The older instars have pale spots on certain abdominal segments, the arrangement of which is characteristic of the species. As the larva grows, it moults (changes skin). They don’t appear to be used for holding prey. The three pairs of legs are used for walking. The larva is dark grey with rows of black tubercles on the dorsal (upper) side of the abdominal and thoracic segments. A long, dark larva hatches from each egg. Female ladybirds lay small groups of yellow eggs on leaves, usually near infestations of prey. The small head has a pair of compound eyes and two short antennae. Like most insects, this ladybird has three pairs of legs that are coloured black. Under the elytra is a pair of wings used for flying. The prothorax (first segment with legs) and the head are black with white areas the prothorax has a pair of white areas at the front and side. The size and arrangement of spots may vary and the small front spots may become very small, almost invisible. The elytra (wing covers) are red with the characteristic 11 black spots. The adults are mainly coloured red and black.
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