An iridescent virus and a microsporidium in the biting midge Culicoides barbosai from Florida.
An iridescent virus and a microsporidium (Nosema sp.) were found infecting larvae of the biting midge Culicoides barbosai collected in Boynton Beach, Palm Beach County, Florida. Larvae were extracted from mud collected weekly during a 22-month period from March 1998 to December 1999. Virus-infected larvae were present in 4 collections made in March, April, and May 1998 and the average infection level was 4.7% (range 2.3-7.1%). The virus infected the fat body and produced an iridescent blue color in larvae because of the crystalline arrays of the particles. These virus particles were hexagonal, measured 99 nm from side to side, and had an electron-dense inner core. The site of infection of the Nosema sp. also was the fat body of the larva, which became opaque white. These opaque areas were the result of masses of oval binucleate spores measuring 2.7+/-0.1 x 4.4+/-0.3 microm (n = 25). The Nosema sp. was present in larvae of 14 collections made during the 22-month period, with an average infection level of 6.1% (range 0.3-21.4%). Although individual larvae infected with the iridescent virus and Nosema sp. occurred in 4 collections, no dual infections were observed. Larvae patently infected with the iridescent virus and Nosema sp. died before pupation.
Fukuda
Tokuo
T
Center for Medical, Agricultural and Veterinary Entomology, Gainesville, FL 32604, USA.
Kline
Daniel L
DL
Day
Jonathan E
JE
D000818:Animals; D002519:Ceratopogonidae / Q000469:parasitology* / Q000821:virology*; D005431:Florida; D017994:Iridovirus / Q000502:physiology*; D007814:Larva / Q000469:parasitology / Q000821:virology; D008854:Microscopy, Electron; D016818:Nosema / Q000502:physiology*