Evidence of Uranotaenia sapphirina (Diptera: Culicidae) feeding on annelid worms in the Northeastern United States.

Abstract

Mosquito host-feeding behavior is an important parameter for determining the vector potential of mosquito species in a given locale. Despite the recent discovery of Uranotaenia sapphirina Osten Sacken feeding on annelid hosts in Florida, host association studies for this mosquito species in the United States remain limited. To investigate the blood-feeding pattern of Ur. sapphirina in the northeastern United States, mosquitoes were collected from Massachusetts, Connecticut, and New Jersey using CDC miniature light traps, peat fiber resting boxes, gravid traps, and backpack aspirators. Vertebrate and invertebrate hosts of this mosquito species were identified through PCR amplification and nucleotide sequencing of portions of the mitochondrial cytochrome b gene and the 28S ribosomal RNA gene, respectively. Of 21 (24.7%) specimens successfully identified to host species, 47.6% contained solely annelid blood, 14.3% mammalian blood, 14.3% avian blood, and 23.8% with mixed blood of annelid and avian origin. The mud earthworm, Sparganophilus tennesseensis Reynolds (Haplotaxida: Sparganophilidae), was identified as the most common host (n = 14, including mixed bloods), followed by American robin, Turdus migratorius (n = 7, including mixed bloods). Testing of these blood engorged mosquitoes for West Nile virus and eastern equine encephalitis virus did not result in any positive specimens. This is the first report of Ur. sapphirina feeding on annelids and on both vertebrate and invertebrate hosts in mixed bloodmeals in the northeastern United States. Our findings support the recent report of Ur. sapphirina feeding on invertebrates and further emphasizes the inclination of some mosquito species to feed on a wider range of hosts spanning nontraditional taxonomic groups.