First reports of Quadrastichus erythrinae in Guadeloupe and Martinique
The presence of Quadrastichus erythrinae (Hymenoptera: Eulophidae) has recently been reported from Guadeloupe and Martinique. In May 2012, this gall wasp was found in Fort-de-France (Martinique) and Baie-Mahault (Guadeloupe) on Erythrina variegata var. fastigiata (Fabaceae). On both islands, these trees were introduced 30 years ago essentially to be planted as windbreaks around banana plantations. Extensive tree mortality has been observed and growers are now recommended to plant Dracanea fragans to replace their destroyed hedges.
The erythrina gall wasp, Q. erythrinae was first described in 2004 from specimens collected from Erythrina spp. in Singapore, Mauritius and Réunion. Erythrinas (coral trees) are tropical and sub-tropical trees which are used as ornamentals, shade trees, trellis support (e.g. to grow betel nut, black pepper, vanilla, yam), windbreaks, for soil and water conservation, as well as for traditional medicine. Q. erythrinae induces galls on the leaves, petioles, twigs and shoots of several Erythrina species. Severe infestations can cause curling of young shoots, defoliation and tree death. Following its initial description, Q. erythrinae spread very rapidly and across huge distances to several countries in Asia, the Pacific (e.g. Hawaii), North America (Florida, US) and most recently in the Caribbean (Guadeloupe and Martinique). This invasive species is causing severe damage and threatens endemic Erythrina species (e.g. E. sandwicensis in the Pacific). Since the beginning of the invasion, it has been suspected that Q. erythrinae originates from Eastern Africa. Recent studies have shown that it occurs naturally in Tanzania where its populations are limited by several parasitoids. However, its detailed distribution in Eastern Africa and the geographic origin of the invasion remain unknown. Research projects are on-going to identify potential biological agents which could be used to control Q. erythrinae.
The currently known distribution of Q. erythrinae is as follows:
Africa: Mauritius, Réunion, Seychelles, Tanzania (native).
North America: USA (Florida, Hawaii).
Caribbean: Guadeloupe, Martinique.
Asia: China (Aomen (Macau), Fujian, Guangdong, Hainan, Xianggang (Hong Kong)), India (Karnataka, Kerala, Maharashtra, West Bengal), Japan (Ryukyu Archipelago), Malaysia, Philippines, Singapore, Sri Lanka, Taiwan, Thailand, Vietnam.
Oceania: American Samoa, Guam.
Etienne J, Dumbardon-Martial E (2013) Quadrastichus erythrinae Kim : un redoutable ravageur pour les érythrines de Guadeloupe et de Martinique (Hymenoptera, Eulophidae, Tetrastichinae). Bulletin de la Société entomologique de France 118(2), 155-158.
CABI (2009) Quadrastichus erythrinae. Distribution Maps of Plant Pests no. 722. CABI Wallingford (GB).
Gerlach J, Madl M (2007) Notes on Erythrina variegata (Linnaeus 1754) (Rosopsida: Fabaceae) and Quadrastichus erythrinae Kim 2004 (Hymenoptera: Chalcidoidea: Eulophidae) in Seychelles. Linzer Biologische Beiträge 39(1), 79-82.
Messing RH, Noser S, Hunkeler J (2008) Using host plant relationships to help determine origins of the invasive Erythrina gall wasp, Quadrastichus erythrinae Kim (Hymenoptera: Eulophidae). Biological Invasions 11(10), 2233-2241.
Lit IL Jr, Caasi-Lit MT, Balatibat JB, Palijon AM, Larona AR, Borja AJD (2010) Postscript to an invasion: the erythrina gall wasp, Quadrastichus erythrinae Kim (Hymenoptera: Eulophidae), in the Philippines. Philippine Entomologist 24(2), 100-121 (abst.).