Ibalia leucospoides

These two subspecies belong to the species Ibalia leucospoides:^[2]

• Ibalia leucospoides ensiger Norton, 1862
• Ibalia leucospoides leucospoides (Hochenwarth, 1785)

This species is widespread in Africa, Australia, most of Europe and Northern Asia (excluding China), North America, and Southern Asia.^[1][3][4][5]

These ibaliid wasps mainly can be found in forests dominated by various conifers genera (Abies, Cupressus, Libocedrus, Picea, Pinus and Tsuga species).^[6] This species has been introduced into conifer plantations of various countries to exert biological control pressure on pest populations.^[6]

Ibalia leucospoides can reach a body length of about 15 mm (0.59 in). These small wasp have black head, thorax and legs. Abdomen is dark red, rectangular, pronouncedly compressed laterally and unmarked.^[4] Antennae are filiform, with 13 antennal segments in males (11 in females). The wings are transparent, with semitransparent apical ends.^[6] This species is rather similar to Ibalia anceps, that shows a different color pattern.^[4]

This species has one generation a year (univoltine), typically coinciding with host emergence. Adults can be found from April to December, depending on location. Females lay eggs on the egg or first instar larvae of siricids. In fact, these wasps are solitary parasitoids of woodwasps (Siricidae family),^[6] especially Sirex, Urocerus and Xeris species.^[4][6][7] The oviposition sites of siricids presumably are located through the sense of smell. When the parasitoids emerge, they feed on the remains of larvae of the woodwasps, until they pupate.^[6]