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Aphid predator (Hemiptera : Nabidae)

Himacerus apterus

Tree damsel bug

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

Identification & Distribution

The adult Himacerus apterus has rather short reddish-brown wings (see pictures below), not reaching beyond the 3rd or 4th abdominal segment (cf. the smaller Himacerus mirmicoides which has relatively longer wings extending over about three quarters of the abdomen). Himacerus apterus has a black connexivum with orange-red spots, clearly visible in both pictures below.

As its English name indicates, Himacerus apterus is a tree-dwelling species on deciduous and, less commonly, on coniferous trees. It feeds on mites and various small insects including aphids. The tree damsel bug is found in most of Europe, and southern and central Asia. There are also historical records of it in Nova Scotia.

 

Biology & Ecology

The nymph of Himacerus apterus is somewhat ant-like in appearance (see picture below).

However, the resemblance is not as close as in its close relative, the ground-dwelling Himacerus mirmicoides (see picture below).

Himacerus mirmicoides: Copyright Line Sabroe under a Creative Commons Attribution 2.0 Generic license. 

Himacerus mirmicoides has spiny posterior angles of the 2nd and 3rd thoracic segments, and the margins of these segments are white, giving the illusion of a narrow waist as found in ants. Ant-like appearance or mimicry (myrmecomorphy) has evolved more than 70 times among insects and spiders (Durkee et al., 2011 ). Most myrmecomorphic spiders are thought to be Batesian mimics, resembling unpalatable models. Himacerus mirmicoides is also a voracious predator, taking aphids from flower stems as shown in an image of a Himacerus mirmicoides larva eating a Uroleucon aphid on Crepis on this alamy page. 

Yanfang et al. (2012)  studied the predation of Himacerus apterus adults on adults of the psyllid Cacopsylla chinensis in the laboratory. Their functional response fitted a Holling type II model. There was evidence of mutual interference between predators when several were present.

Koschel(1971)  looked at the biology, ethology and ecology of Himacerus apterus. The mean number of eggs laid was only 20.2 per female. The eggs were deposited within the stems of lower plants where they hibernated. Himacerus apterus was very polyphagous. The young larvae fed on small insects and mites living on grasses and herbs. The older instars climbed bushes and trees and may feed on younger Himacerus. The intraspecific behaviour depends on the degree of satiation. The bugs maintain a fixed orientation to the sun. The species avoids agricultural land preferring pine woodland with grass and bushes. The use of Himacerus apterus for biological control of forest pests is problematic because of cannibalism and low fecundity.

 

Biological control of Aphids

Burgio et al. (2006)  found that Himacerus apterus was one of the generalized predators present in weedy field margins around orchards in northern Italy that were contributing to biological control of orchard pests.

Acknowledgements

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 

References

  • Burgio, G. et al. (2006). The role of ecological infrastructures on Coccinellidae (Coleoptera) and other predators in weedy field margins within in northern Italy agroecosystems. Bulletin of Insectology 59(1), 59-67. Full text 

  • Durkee et al. (2011). Ant mimicry lessens predation on a North American jumping spider by larger salticid spiders. Environmental Entomology 40(5), 1223-1231. 75-83. Full text 

  • Koschel, H.(1971). Zur Kenntnis der Raubwanze Himacerus apterus F. (Hetereptesa, Nabidae). Journal of Applied Entomology 68 (1-4), 113-137. Abstract 

  • Yanfang et al. (2012). Predation of Himacerus (Himacerus) apterus to Cacopsylla chinensis adults. (In Chinese). Plant Protection 05Abstract