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Aphid Predator (Coleoptera: Coccinellidae)
Cream spot ladybirdOn this page: Identification & Distribution Biological Control of Aphids: Control in the field Predating sycamore periphyllus aphids Possibly cooley spruce gall adelgids
Identification & Distribution
Calvia quattuordecimguttata is a medium-sized ladybird ranging in length from 4.0-5.5 mm. In Europe the elytra are consistently maroon-brown with fourteen cream-coloured spots. In North America and parts of eastern temperate Asia other varieties also occur. Calvia quattuordecimguttata may be black with white spots, or yellow to pink with eighteen large blotches. Another variety is black with a large red spot on each elytron. The cream spot ladybird underside is black surrounded by a thin red rim.
The Calvia quattuordecimguttata larva is dark grey with pale areas on the dorsum of the thoracic segments and on the head. There is a pair of pale dorsolateral tubercles on abdominal segment I, six pale tubercles across segment IV and pale lateral tubercles bearing tubular papillae on segments IV to VII. The larva has medium length unbranched conical spines on every abdominal segment.
The Calvia quattuordecimguttata larva is dark grey with pale areas on the dorsum of the thoracic segments and on the head. There is a pair of pale dorsolateral tubercles on abdominal segment I, six pale tubercles across segment IV and pale lateral tubercles bearing tubular papillae on segments IV to VII. The larva has medium length unbranched conical spines on every abdominal segment..
The preferred prey of the cream spot ladybird is aphids, but like many coccinellids it will take other prey when available especially psyllids, but also scale insects, mites and even the eggs and larvae of Lepidoptera. Calvia quattuordecimguttata is found in a wide variety of habitats, but is especially characteristic of deciduous broadleaved woodlands, hedges, orchards, parks and gardens. It is widely distributed being found throughout Europe, most of Asia (but excluding the Indian subcontinent, south-east Asia and the southern Arabian peninsula) and most of North America.
Biological Control of Aphids
Aphid control in the field
As far as we know, Calvia quattuordecimguttata has not been used for augmentative releases, and there is surprisingly little recent information in the literature about their diet preference in the field.
Semyanov (1980) found that optimum development of the cream spot ladybird took place when it was feeding on psyllids, especially apple psyllids (Psylla mali). Fecundity was also found to depend on prey species. A female feeding on Psylla mali laid a maximum of 243 eggs, while one feeding on the aphid Hyalopterus pruni laid up to 46 eggs only. Semyanov (1996) notes that Calvia quattuordecimguttata was one of the coccinellid predators found in orchards in the Leningrad region where it played an important role in reducing the number of apple psyllids.
Godeau & Ceryngier (2013) identified prey items in the frass (=faeces) of three ladybird species living on black alder. The available aphids were Clethrobius comes and the available psyllids were Psylla alni (see picture below). Other potential prey were chrysomelid larvae, bark lice (Psocoptera), ciccadellids, thrips and mites.
Their frass analysis revealed that 75% of adult cream spot ladybirds had eaten aphids, 42% had eaten psyllids and 17% had eaten bark lice. 80% of cream spot ladybird larvae had eaten aphids.
Danilov et al. (2016) recorded Calvia quattuordecimguttata predating aphids on two plum species Prunus cerasifera and Prunus domestica in Lithuania. Although the aphids Hyalopterus pruni and Brachycaudus divaricatae were both present on the trees, the cream spot ladybird was only recorded predating Hyalopterus pruni.
Note that the experimental work by Kalushkov & Hodek (2001) on new 'essential' prey for Anatis ocellata and Calvia quatuordecimguttata is rather misleading since the prey used in the experiments were chosen on the basis of availability to the researcher, rather than those that would normally be available to the coccinellid.
Predation of sycamore periphyllus aphids
Cream spot ladybirds can often be found on sycamore trees where they feed on the rich variety of aphids and other soft bodied insects that live on sycamore.
The pair above were mating, most likely having eaten some of the Periphyllus testudinaceus aphids that were around the base of the same leaf (see picture below).
Possible predation of cooley spruce gall adelgids
The cream spot ladybird is not often found on conifers, but the ladybird below was found on Douglas fir.
This ladybird may have been eating the immature adelgids or, since the picture was taken in January, simply using the conifer as an appropriate sheltered place to hibernate.