Ruby-tailed wasp  (Chrysis pseudobrevitarsis)

Ruby-tailed wasp

Facts

Kingdom Animalia
Phylum Arthropoda
Class Insecta
Order Hymenoptera
Family Chrysidae
Genus Chrysis(1)

Status

This very rare species is classified as Vulnerable in Britain (2).

Description

This vulnerable and beautiful ruby-tailed wasp has a striking appearance. As the common name suggests, it has a brilliant ruby-coloured abdomen and the thorax is iridescent and brightly coloured. It is a parasitoid of the scarce eumenid wasp Ancistrocerus antilope (1) .

Range

Definite confirmed records of this species have occurred in Northamptonshire in 1947, and north Devon from 1979 to 1985, and again in 1989 (2). An old record has been reported for Woking in Surrey, but this has not been confirmed, and the host wasp is not found in this area (2).

You can view distribution information for this species at the National Biodiversity Network GatewayDisplay NBN Map Button

Habitat

The host is found in a range of habitats, but seems to have a preference for old buildings with loose or crumbling mortar and sandy and earthy banks, in which it nests (2). It is also associated with farmyards and derelict stone buildings (2).

Biology

This ruby-tailed wasp is a parasitoid of the host eumenid wasp (Ancistrocerus antilope) larvae. Females lay their eggs in the host larvae; the eggs hatch out and the larvae of the ruby-tailed wasp then develop inside the host. The host wasps lays their eggs inside cavities in walls, holes in earthy or sandy banks and in old beetle burrows in wood, and provide small caterpillars as a food source for the young. Adults of this species of ruby-tailed wasp have been recorded from May to July (2).

Threats

This rare ruby-tailed wasp appears to be vulnerable to changes in the populations of its host. Other potential threats include the decrease in availability of old buildings with crumbling mortar, dead wood and sandy or earthy banks. Agricultural intensification and increasing urbanisation may also be problems (2).

Conservation

At known sites for this species, old stone buildings and walls, and sandy or earthy banks should be preserved to retain suitable nesting sites for the host wasp. Management may be needed to keep natural succession in check (2).

Authentication

Authenticated (06/06/05) by Mike Edwards, Sussex county recorder for ants, bees and wasps.

Glossary

Abdomen: In arthropods (crustaceans, insects and arachnids) the abdomen is the hind region of the body, which is usually segmented to a degree (but not visibly in most spiders). In crustacea (e.g. crabs) some of the limbs attach to the abdomen; in insects the limbs are attached to the thorax (the part of the body nearest to the head) and not the abdomen. In vertebrates the abdomen is the part of the body that contains the internal organs (except the heart and lungs).
Larvae: Stage in an animal's lifecycle after it hatches from the egg. Larvae are typically very different in appearance to adults; they are able to feed and move around but usually are unable to reproduce.
Natural succession: The progressive sequence of changes in vegetation types and animal life within a community that, if allowed to continue, result in the formation of a ‘climaxcommunity' (the last stage in a succession where the vegetation reaches equilibrium with the environment).
Parasitoid: An insect that lives in or on a host that is also a parasite on another species. If the parasite kills the host it is commonly called a parasitoid.
Thorax: Part of the body located near the head in animals. In insects, the three segments between the head and the abdomen, each of which has a pair of legs.

References

  1. National Biodiversity Network Species Dictionary (February, 2004)
    http://www.nhm.ac.uk/nbn
  2. Falk, S. (1991) A review of the scarce and threatened bees, wasps and ants of Great Britain - Survey and research in Nature Conservation. No. 35. JNCC, Peterborough.