Description & Statistics

Eumeninae (Eumenidae). -- The powder wasps construct mud or stick shelters. These wasps sting many pest insects to death, and can store 6-8 caterpillars in each cell.

Eumenidae are solitary insects, showing much variety in the location and manner of forming the cell to receive prey. Some build vase-like or spherical cells of mud, clay, sand or masticated leaf tissue that are fastened to twigs or other objects. Other species utilize tubular cavities in stems and partition off each successive cell. A number of species make burrows in the soil, and a few utilize the abandoned cells of other wasps (Clausen 1940/1962).

Most eumenids provision the nest with larvae of Lepidoptera, although some also utilize larvae of Tenthredinidae and Chrysomelidae. The family is regarded as completely beneficial. Each cell is provided with a number of paralyzed larvae, the egg being laid just before the cell is closed. Species of the genus Synagris exhibit some departures from the normal behavior of the family. Female S. cornuta L. places the egg in the cell as soon as it is completed, and no provisions are brought in until after hatching (Roubaud 1910). Caterpillars are never brought to the nest, but the parent female feeds the larva periodically with chewed bits of the body contents of freshly killed prey. Caterpillars are placed in the cell at certain intervals by S. sicheliana Sauss, and it is closed when the larva is about 3/4ths mature, this behavior of maternal care being recorded in several other genera.

Eggs are usually elongated and have a stalk at one end which in some species is longer than the egg body and by means of which it may be suspended from the cell wall. The hatched larva may retain its attachment to the eggshell for some time after hatching.

Hunting behavior of Odynerus herrichi Sauss. was studied by Spooner (1934), who found that the female searches for a tortricid larva, on which it preys, in its web, bites a hole in the top and then thrusts its stinger through the web. Because of this disturbance, the caterpillar emerges through the hole and drops to the ground. Then the wasp drops perpendicularly to the ground also, captures the caterpillar and carries it to the nest. If not found on the first attempt, the wasp returns to the plant, finds the hole in the web, and again drops to the ground to search for the caterpillar (Clausen 1940/1962).

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References: Please refer to <biology.ref.htm>, [Additional references may be found at: MELVYL Library ]

Carpenter, J. M. (1986). "A synonymic generic checklist of the Eumeninae (Hymenoptera: Vespidae)" (PDF). Psyche 93: 61–90. http://psyche.entclub.org/pdf/93/93-061.pdf.

Carpenter, J. M. & B. R. Garcete-Barrett. 2003. A key to the neotropical genera of Eumeninae (Hymenoptera: Vespidae). Boletín del Museo Nacional de Historia Natural del Paraguay 14: 52–73.

CSIRO Entomology Division. 1991. The Insects of Australia: a textbook for Students and Research. 2nd Edition. Melbourne University Press and Cornell University Press. 1137 pp.

Giordani Soika, 1989. Terzo contributo alla conoscenza degli eumenidi afrotropicali (Hymenoptera). Societa Veneziana di Scienze Naturali Lavori 14(1) 1989: 19–68.

Giordani Soika, A. 1992. Di alcuni eumenidi nuovi o poco noti (Hymenoptera Vespoidea). Societá Veneziana di Scienze Naturali Lavori 17 1992: 41–68.

Giordani Soika, A. 1993. Di alcuni nuovi eumenidi della regione orientale (Hym. Vespoidea). Bollettino del Museo Civico di Storia Naturale di Venezia 42, 30 giugno 1991(1993): 151–163.

Gusenleitner. 1992. Zwei neue Eumeniden-Gattungen und -Arten aus Madagaskar (Vespoidea, Hymenoptera). Linzer Biologische Beiträge 24(1) 1992: 91–96.