Ophelimus bipolaris sp. n. (Hymenoptera, Eulophidae), a New Invasive Eucalyptus Pest and Its Host Plants in China

Simple Summary Eucalyptus species have become one of the most commonly planted trees worldwide, including China. However, the productivity of Eucalyptus plantations has been threatened by the recent increase of invasive insect pests. Gall inducers of the genus Ophelimus (Eulophidae) are among the most important invasive species in Eucalyptus plantations. Based on the combined analysis of biological, morphological and molecular evidence, we here describe a new invasive species, Ophelimus bipolaris sp. n., from China. This wasp induces galls only on the leaf blade surface of four Eucalyptus species. It can complete a life cycle on E. urophylla in approximately 2 months under local climatic conditions in Guangzhou, China. Eucalyptus species have become one of the most commonly planted trees worldwide, including China, due to their fast growth and various commercial applications. However, the productivity of Eucalyptus plantations has been threatened by exotic invasive insect pests in recent years. Among these pests, gall inducers of the genus Ophelimus of the Eulophidae family are among the most important invasive species in Eucalyptus plantations. We report here for the first time the presence of a new invasive Eucalyptus gall wasp, Ophelimus bipolaris sp. n., in Guangzhou, China, which also represents the first species of the genus reported from China. The identity of the new species was confirmed by an integrative approach combing biological, morphological and molecular evidence. The new species is described and illustrated. This wasp induces galls only on the leaf blade surface of four Eucalyptus species: E. grandis, E. grandis x E. urophylla, E. tereticornis and E. urophylla. Our preliminary observation showed that O. bipolaris could complete a life cycle on E. urophylla in approximately 2 months under local climatic conditions (23.5-30 degrees C). Considering the severe damage it may cause to Eucalyptus production, further investigations of its biology and control are urgently needed in China.

Automated summary

Eucalyptus species are among the most commonly planted trees worldwide, including China, due to their fast growth and various commercial applications. However, the productivity of Eucalyptus plantations has been threatened by recent increase of invasive insect pests, particularly gall inducers of the genus Ophelimus. A new invasive species, Ophelimus bipolaris sp. n., inducing galls on the leaf blade surface of four Eucalyptus species, has been described from China. This wasp can complete a life cycle on E. urophylla in about 2 months under local climatic conditions in Guangzhou, China. Further investigation on its biology and control are urgently needed in China to mitigate the potential damage to Eucalyptus production.