Description of four new species of Eadya (Hymenoptera, Braconidae), parasitoids of the Eucalyptus Tortoise Beetle (Paropsis charybdis) and other Eucalyptus defoliating leaf beetles

Abstract

EucalyptusL’Héritier, 1789 (Myrtales: Myrtaceae) plantations are a global economic resource with a wide array of uses. As this forestry crop grows in popularity around the world, the exotic introduction of pests such as the leaf beetles belonging to the generaParopsisOliver, 1807 andParopsisternaMotschulsky, 1860 increases in frequency. These pest introductions have spurred a need to understand the natural enemies of these pests for use in classical biological control programs. One such enemy,EadyaparopsidisHuddleston & Short, 1978 (Hymenoptera: Braconidae), has shown potential as a biological control agent againstParopsischarybdis, an exotic pest of New ZealandEucalyptusplantations. However, observations made by biocontrol researchers have raised concerns thatE.paropsidisis a complex of cryptic species. A comprehensive large-scale phylogenetic study utilizing both host and molecular data (Peixoto et al. 2018), as well as a morphological multivariate ratio analysis, was utilized to ensure accurate delimitation of the species ofEadya. Here we formally describe the three new species (EadyaannleckieaeRidenbaugh, 2018,sp. n.,EadyadaenerysRidenbaugh, 2018,sp. n.,EadyaspitzerRidenbaugh, 2018,sp. n.), and one additional new species discovered in the Australian National Insect Collection (EadyaduncanRidenbaugh, 2018,sp. n.). All distributions and host associations forEadyaare listed as well as a redescription of the originally describedE.paropsidisandE.falcata. An illustrated key to all known species is included to assist biological control researchers. The value of citizen science observations is discussed, along with the need for a further understanding of mainlandEadyapopulations given the recent spread of paropsine pests. Finally, we discuss the subfamilial placement ofEadya, and suggest it belongs within Euphorinae based on morphological characters.