Phenacoccus miruku: an invasive mealybug in Florida (US)
Phenacoccus miruku (Hemiptera: Pseudococcidae) was first described in 2022 from Japan. This new mealybug species was found in Okinawa Island (Kyushu) on Bidens pilosa var. radiata (syn. B. pilosa) (Asteraceae).
In 2019, an unknown mealybug was observed on the roots of Bidens alba (a common roadside perennial), in Lake county, Florida, USA. In subsequent months, this mealybug rapidly spread to other locations and expanded its host range, thus showing an invasive behaviour in Florida. At that time, this mealybug was identified as Phenacoccus sisymbriifolium, and it was only in the light of the new description made in Japan, that the pest could be finally identified as Phenacoccus miruku.
From 2019 to 2024, P. miruku was found in 20 counties of Florida (Alachua, Brevard, Broward, Collier, Dixie, Hernando, Hillsborough, Indian River, Lake, Marion, Okaloosa, Orange, Palm Beach, Pasco, Polk, Putnam, St Johns, St. Lucie, Sumter and Volusia). It was observed feeding on more than 20 host plants from 10 families, the most common host being Bidens alba. P. miruku was found on tomato (Solanum lycopersicum), aubergine (S. melongena), Capsicum and sweet potato (Ipomoea batatas) in both outdoor gardens and greenhouses. As this mealybug shows a preference for Solanaceae and Asteraceae, it is considered that it has the potential to become a pest of vegetables and ornamentals. In Florida, P. miruku was mostly found on the roots and sometimes on the crown of its host plants. It was also frequently observed in association with the red imported fire ant, Solenopsis invicta. On B. alba, P. muruku was found in mixed infestations with other scale insects: Phenacoccus solani and Pseudococcus sorghiellus. Mixed infestations with Planococcus citri were also observed on Solanum quitoense and S. lycopersicum, as well as on the invasive alien plant Ambrosia artemisiifolia. It is concluded that P. miruku should continue to be monitored in Florida to evaluate its potential damage to crops.
A distribution map and a list of host plants of P. miruku have been added to the EPPO Global Database:
https://gd.eppo.int/taxon/PHENMK/distribution
https://gd.eppo.int/taxon/PHENMK/hosts
Sources
Powell EC, Deeter LA, Moore MR, Ahmed MZ & Miller DR (2024) Taxonomy, hosts, and distribution of an emerging invasive mealybug, Phenacoccus miruku (Hemiptera: Coccomorpha: Pseudococcidae), in Florida. Florida Entomologist 107(s1), 20240024. https://doi.org/10.1515/flaent-2024-0024
Tanaka H, Sasaki D, Choi J, Husnik F & Kamitani S (2022) Two new species of mealybugs (Hemiptera: Coccomorpha: Pseudococcidae) from Japan. Zootaxa 5168(3), 306–318.