Insect of the Month

May 2022: Dasymutillini (Mutillidae), Velvet Ants

Dasymutillini are a tribe of velvet ants. The common name comes from their look, with the hairs resembling velvet and their form resembling ants, however they are actually wasps. The female (on the bottom) has no wings, while the male (on the top) is winged. Different species are either black or may also have bright orange/red and often have white or silver markings. Bright colours in insects are often signals of danger, in this case the danger is their sting. The sting can be very painful but is only used if they are threatened. Adults feed on nectar while eggs are laid into nests of ground nesting bees or wasps. The larvae attach themselves to the outside of the host (ectoparasitoid) which has been immobilised and does not develop, remaining as a larvae or pupae (idiobiont). This pair was photographed by Dr Sue Jaggar, at Nanson, WA. It is unusual to see the male active during the day.

April 2022: Paragia tricolor (Masarinae) and Hyptiogaster sp (Gasteruptiidae)

There was a mass emergence of Paragia tricolor on a property in Bridgetown, WA, with most of the 2 acre property covered by nests. P. tricolor are pollen wasps that build nests in the ground with and collect pollen and nectar from Corymbia and pack it in the nest to provision their larvae (Houston 1986). The Hyptiogaster is a parasitoid that lays it’s eggs in the nest. Photographs by Dr Sue Jaggar.

(a) P tricolor building a tunnel entrance to the nest. They flew to the river and came back with water, which they used to make mud, and shaped the nest entrance which covered the vertical tunnels that formed the main part of the nest. These horizontal tunnel entrances were up to 10cm long. You can see the wet patch on the top of the tunnel which is being shaped by the wasp. The temperature was in the 30’s so the mud dried quickly.

(b) A mating pair of P tricolor.

(c) A mating swarm of P tricolor some of these mating groups had up to 100 wasps in them. The mating groups mainly occurred in the morning.

(d) The black cloud in front of the trees an over the ground is hundred of thousands of P. tricolor. Early in the morning they all seemed to be in flight, later in the day they were mostly on the ground.

(e) H. sp flying around searching for a potential nest

(f) H. sp checking a nest to see if it contains provisions.

(g) H. sp backing into the nest to oviposit

(h) Nests covering the ground, with P. tricolor busy making extensions.

March 2022: Ceriana sp (Syrphidae)

Ceriana sp on Melaleuca, observed in Kings Park, Perth by Dr Sue Jaggar. Ceriana are wasp mimicing hoverflies, the antennae are lengthened compared to most hoverflies, similar to wasps, they resemble Eumeninae (Potter wasps). There are 23 known species of Ceriana in Australia. The larvae of some members of the tribe Cerioidini are saproxylic (feeding on dead or decaying wood), some with association with tree sap. Adult females have been observed ovipositing onto the bark of trees. Ceriana ornatam is a species (common in Queensland) that is known to attack native sugar bag bee hives (a social group of native bees) and have adapted to honeybee hives. The larvae chew through the hive. It is thought they may have moved from Queensland to other states with the movement of bee hives.

February 2022: Stomorhina sp (Rhiniidae)

Stomorhina sp on daisy, observed in Stirling Gardens, Harvey by Dr Sue Jaggar. They were originally classified as Calliphoridae (blowflies) but have been reclassified so they belong to the Rhiniidae family, commonly known as pointy nosed flies. Stomorhina are often seen on flowers and have been recorded as good pollinators of Mango (Jaggar 2015). It is possible this is Stomorhina pollinosa. Little is known of the biology of this genus, although in Africa Stomorhina lunata are known to be egg predators on locust eggs (Greathead 2009) and the larvae of Stomorhina discolor (I have observed in good numbers on Mango in Queensland) have been found in ant nests and in roots where boring beetles are present (Moophayak et. al. 2017).

January 2022: Bembicinus sp

Bembicinus sp observed in Westralia Conservation Park (near Collie) by Dr Sue Jaggar. Bembicinae are sandwasps, they dig nests in the sand, lay eggs on a sand pedicel inside the nest and collect insects (like Hemiptera (true bugs) or grasshoppers) to pack in the nests with their eggs so that the young have food when they emerge. In this image the wasp is extending the nest. They are active between 25 and 45oC. They nest in aggregation. I saw 5 or 6 wasps active in the same area.

December 2021: Neosardus paramonovi

A Bombyliidae (beefly) observed in Lesueur National Park by Dr Sue Jaggar. Bombyliidae are pollinators as adults and parasitoids of other insects during their larval stage. More research is required to determine the hosts for larvae of many Bombyliidae species. Thanks to Dr Christine Lambkin for the ID to species level. In Yeates (1996) this species is only recorded in Perth (Ascot, Upper Swan, Gnangara, Wanneroo and Bullsbrook) and the only record in Atlas of Living Australia and iNaturalist is this one in Lesueur National Park. The green coloration on the thorax is only observed in live specimens.

References used:

Greathead, D.J., (2009). The biology of Stomorhina lunata (Fabricus), predators of the eggs of Acrididae. Journal of Zoology 139(1): 139-180

Houston, T. F. (1986). Biological notes on the pollen wasp’Paragia (Cygnaea) vespiformis'(Hymenoptera: Vespidae: Masarinae) with description of a nest. Australian Entomologist, The12(6), 115-118.

Jaggar, S. (2015). Wild insects are efficient pollinators of Mango (Mangifera indica) in the Mareeba region, Qld. [Unpublished Masters Thesis] The University of New England.

Moophayak, K., Sanit, S., Chaiwong, T., Sukontason, K., Kurahashi, H., Sukontason, K. L., . . . Bunchu, N. (2017). Morphological Characteristics of Terminalia of the Wasp-Mimicking Fly, Stomorhina discolor (Fabricius). Insects, 8(1), 11.

Yeates, D.K. (1996). Revision of the Australian bee fly genus, Neosardus (Roberts). Invertebrate Taxonomy, 10(1), 47-75.