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.
Pogonomyrmex barbatus is a species of harvester ant from the genus Pogonomyrmex. Its common names include red ant and red harvester ant. These large (5â to 7-mm) ants prefer arid chaparral habitats and are native to the Southwestern United States. Nests are made underground (up to 2.5 m deep) in exposed areas.