Caterpillar hunting wasp  (Delta dimidiatipenne)

The caterpillar hunting wasp has yet to be assessed by the IUCN.

Named for its habit of hunting caterpillars to feed its young, the caterpillar hunting wasp (Delta dimidiatipenne) belongs to one of the largest orders of insects, the Hymenoptera, which includes the wasps, bees and ants (3) (4). All of the insects in this group have compound eyes, two ocelli, biting mouthparts, and two pairs of membranous wings which are linked together during flight by tiny hooks (3). 

The caterpillar hunting wasp has a dull red head, with black markings from behind the eyes to the top of the head, which extend to the back of the neck. The thorax is black, except for two red patches on the second segment and on the upper parts of the third and last segments (2). The thorax and the first segment of the abdomen are fused together, creating a narrow ‘waist’ which is red with some black at the base (2) (3). The abdomen is mainly black, apart from a red band just below the waist. The wings are rust-coloured with grey-brown tips, and may sometimes have a purplish tinge. The tips of the antennae are usually black (2).

The male caterpillar hunting wasp is similar in appearance to the female, although it is slightly smaller and more slender, with a yellow face (2).  

A wide-ranging species, the caterpillar hunting wasp is found from northwest Africa, Egypt and Somalia, throughout the Middle East, and east to India and Nepal (2) (5). The caterpillar hunting wasp is also found in the Canary Islands, where it has recently become established and is now widespread (5). 

The caterpillar hunting wasp is known from a variety of desert habitats (6). 

Nest building is a characteristic behaviour of the caterpillar hunting wasp. The female constructs a nest from sand or mud (3), using its jaws to feed the dry material into the scooped front legs and mixing it with saliva from the mouth to form a kind of plaster (4) (6). The wasp then lays down pellets of mud by dribbling the wet clay onto the nest, moulding the material into a small mud pot (3) (4) (6). The caterpillar hunting wasp uses its antennae to gauge the shape and size of the nest, finishing it off by adding a slight lip to the entrance (3) (7). The nest is hung from walls or rocks and hardens as it dries (3) (7).

Once the nest is complete, the female caterpillar hunting wasp lays a single egg inside the chamber, suspending it from the roof by a thread of silk (3) (6) (7). The female provisions the nest with several caterpillars, which are eaten by the larva during its development inside the nest (4) (7). The adult caterpillar hunting wasp feeds on nectar (2).  

There are no known threats to the caterpillar hunting wasp.

There are no known conservation measures in place for the caterpillar hunting wasp.

Environment Agency - Abu Dhabi is a principal sponsor of ARKive. EAD is working to protect and conserve the environment as well as promoting sustainable development in the Emirate of Abu Dhabi.

Find out more about insects of the Middle East:

• Walker, D.H. and Pittaway, A.R. (1987) Insects of Eastern Arabia. Macmillan Publishers Ltd., London. Available at:
  http://www.enhg.org/resources/ebooks/IOEA/InsectsOfEasternArabia.pdf.

Find out more about conservation in the United Arab Emirates:

• Abu Dhabi Environment Agency:
  http://www.ead.ae/en