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Aphid predator (Hemiptera : Miridae)

Deraeocoris ruber

Red-spotted plant bug

On this page: Identification & Distribution Biology & Ecology Biological Control of Aphids

Identification & Distribution

The adult Deraeocoris ruber is a rather wide medium sized bug. The dorsal surface is very shiny and varies in colour from red-orange to black (see pictures below showing variation from mainly red to mainly black). The first antennal segment and at least the base of the second are black. The body length of the adult ranges from 6-8 mm. Nymphs are crimson reddish with a characteristically wide abdomen bearing black spines.

Deraeocoris ruber black form: Copyright Didier Descouens under a Creative Commons Attribution 4.0 International License

Deraeocoris ruber is found on a variety of herbs, shrubs and trees. It especially likes the common nettle (Urtica dioica), which is where it was found in the first of the pictures above. It feeds on nettle, and is predatory on aphids and other small insects. The red-spotted plant bug is found throughout the holarctic region.


Biology & Ecology

Deraeocoris ruber has one generation per year. Eggs are laid singly in 1-2 year old wood in late summer, and hatch the following year in early summer. The red-spotted plant bug is mainly predatory (Encyclopedia of Life), but may also feed on nettle. They may attack other predators, and are cannibalistic. The black Deraecoris in the picture above is almost certainly preying on the young Uroleucon nymphs in the picture. Surprisingly we have yet to find it feeding on the common nettle aphid (Microlophium carnosum). Deraeocoris ruber has also been observed to scavenge prey from the web of a spider (Hamm, 1916 in Wheeler, 2001) and is also known to feed on the broom psyllids Arytaina spartii and Arytaina genestai (Jerinic-Prodanovic & Protic (2013))

Wheeler (2001) describes how Deraeocoris ruber uses its comblike protibial structure to push the prey remains off the end of the rostrum. After removal, the combs are pushed repeatedly down the rostrum and cleaned by rapid flicking of the forelegs. Between bouts of predation, Deraeocoris ruber nymphs eject fluids from the rostrum on to a surface and suck it in and out several times.


Biological control of Aphids

We have found Deraeocoris ruber feeding on Aphis fabae cirsiiacanthoidis on thistle (see picture below).

In apple orchards Marchal (1929) reported that Deraeocoris ruber feeds on woolly apple aphid (Eriosoma lanigerum) as well as psyllids and mites. They are mainly found in weedy orchards with nettles. Dicker, 1952 reports that Deraeocoris ruber are predators of the strawberry aphid (Chaetosiphon fragaefolii). In filbert (hazelnut) orchards Viggiani (1971) found the red-spotted plant bug to be an important predator of both the large hazel aphid (Corylobium avellanae) and the small hazel aphid (Myzocallis coryli).


For the mirid bugs we have used Southwood & Leston (1959) and British Bugs to aid in identification and for the key characteristics.

For aphids we have made provisional identifications from high resolution photos of living specimens, along with host plant identity. In the great majority of cases, identifications have been confirmed by microscopic examination of preserved specimens. We have used the keys and species accounts of Blackman & Eastop (1994) and Blackman & Eastop (2006) supplemented with Blackman (1974), Stroyan (1977), Stroyan (1984), Blackman & Eastop (1984), Heie (1980-1995), Dixon & Thieme (2007) and Blackman (2010). We fully acknowledge these authors as the source for the (summarized) taxonomic information we have presented. Any errors in identification or information are ours alone, and we would be very grateful for any corrections. For assistance on the terms used for aphid morphology we suggest the figure provided by Blackman & Eastop (2006).

Useful weblinks


  • Dicker, G.H.L. (1952). Studies in population fluctuations of the strawberry aphid Pentatrichopus fragaefolii. I. Enemies of the strawberry aphid. Reports of the East Malling Research Station 39, 166-168. Google Scholar

  • Encyclopedia of Life. Deraecoris ruber Full text

  • Jerinic-Prodanovic, D. & Protic, L. (2013). True bugs (Hemiptera, Heteroptera) as psyllid predators (Hemiptera, Psylloidea). Zookeys 319, 169-189. Google Scholar

  • Marchal , P. (1929). Les enemis du puceron lanigè, conditions biologique et cosmiques de sa multiplication. Traitements. Ann. Epiphyt. (Paris) 15, 125-181.

  • Viggiani, G. (1971). Biological observations on the predatory mirid Deraeocoris ruber (L.) (Rhynchota, Heteroptera) Bolletino del Laboritoriodi Entomologica Agraria 'Filippo Sylvestri' Portici 29, 270-286.

  • Wheeler, A.G.W. (2001). Biology of the Plant Bugs (Hemiptera: Miridae). Cornell University Press.