The BVD stands for Back Vertex Distance, this is a measurement that is included on any prescription where the sphere or cylinder powers are higher than + or - 5.00D and to a lesser extent some prescriptions where it is less than this power.
Winged Drone | Alate | Male Ant. Drones are the only male ants in a colony. They are born from un-fertilized eggs. Drones are not like typical ants. They donât do any work in their nests, and they look more like wasps than ants. They are reproductive winged ants and so are alates.
These are the house-invading ants, nuisance ants or simply house ants. Common house ant species are: odorous house ant, Argentine ant, pharaoh ant and a few other species. Most ants that invade homes are yellow, red, brown or black in color, constricted at the waist, and 1/8-1/4 long. If you find ants that are larger than about 3/8 (in the US) you've probably found carpenter ants.