The Aedes Aegypti, Yellow Fever Mosquito
History and Specifications
The Ae. Aegypti, Yellow Fever Mosquito has been in the United States for centuries but it has not always lived her. Entomologists believe European exploration ships to the new world brought the mosquito here. The species was first named Culex Aegypti in 1757 by Fredric Hasselguist. He gained the names and descriptions by his mentor Carl Linnaeus. Later (around the early 1900’s the name changed to Aedes Aegypti.
An adult Yellow Fever Mosquito is small to a medium-sized bug, about 4 to 7 millimeters in size. The pattern of the Aegypti is much like the Albopictus, and to untrained eyes, they are mistaken for one another. Differences between the two species is a slight difference in size and the thorax pattern. Ae. Aegypti has white scales on the dorsal (top) surface of the thorax that form a violin shape. Ae. Albopictus has white stripes down its thorax. Both the Aegypti and Albopictus have white bands on the hind legs and dark brown to black abdomens.
The female mosquito is larger than the with small palps (the sensory organ she uses to track and find its prey) tipped with silver or white scales. Males have plumose antennae while females have sparse short hairs. The male mosquito has mouthparts changed for nectar feeding while the female has mouthparts that designed for blood feeding. This mouthpart is called a proboscis and both sexes have dark proboscis with a clypeus (part right above the proboscis). The Clypeus has two clusters of white scales. Unlike any other species of mosquito, the tip of the abdomen on the Aegypti comes to a point.
For a full breakdown of the mosquito anatomy, go to our General Mosquito Anatomy blog post.
The left picture is the spread of the Aedes Albopictus, Asian Tiger Mosquito across America. The right picture is the spread of the Aedes Aegypti, Yellow Fever Mosquito across America.
Breeding Habits and Life Cycle
Ae. Aegypti is a holometabolous insect which means it goes through a complete metamorphosis where each part of the egg, larvae, pupa, and adult look different. The average lifespan of the adult yellow fever mosquito can last from two weeks to a month depending on environmental conditions.
The Yellow Fever Mosquito is a container breeder that prefers to use untreated, stagnant water to lay its eggs. This could be anything from an unused flower pot, spare tires, drainage ditches, or even stagnant unmaintained pools. Much like the Aedes Albopictus (Asian Tiger Mosquito) the Ae. Aegypti prefers to breed and live around humans. Unlike, the Ae. Albopictus the Aegypti is a night time flier.
Laying the Eggs:
Also, like other mosquitoes, the male is a nectar feeder while the female feeds on nectar and blood. The female mosquito uses blood she gains from her hosts for the laying of her eggs. It takes a female mosquito 3 days to use all the blood she gets from her feeding to lay all of her eggs. Once she lays her eggs, it will take anywhere from 7 to 10 days for them to develop and hatch. Eggs can survive desiccation (total drying out) for a long time (up to about 6 months is normal). This gives the eggs the ability to transport to new locations without damaging the larvae inside. Once water contacts the egg it can hatch.
The Ae. Aegypti lies on average 100 to 200 eggs per batch but this varies based on the amount of blood she can get. She can produce around 5 batches of eggs in her lifetime. That is around 1,000 eggs just from one mosquito! The female mosquito will lay her eggs on damp surfaces likely to flood at a later time. She most likely won’t lay all of her eggs at one time, instead choosing to spread them out across a wide range of places.
Stages of Growth:
The eggs of Ae. Aegypti are long, smooth, and one millimeter long. They are white when laid but turn a shiny black within minutes. In warm climates the eggs can develop in as little as two days while in cooler climates it can take a week.
Larvae hatch from the eggs and spend their lives in water. They feed on organic particulate matter (algae and microscopic organisms) in the water. They spend most of their life near the top of the water but will swim down to the bottom of the water if they feel they are in danger. Development of the larvae (just like the eggs) relies on temperature. Larvae pass through four instars (phases between two period of molting) in its development to pupae. The larvae spend most time in the fourth instar (up to three days). The male will pupate earlier than the female.
After the fourth instar the mosquito enters the pupal stage (also called “tumblers”). The pupae are mobile and respond to stimuli which varies from many other holometabolous insects. The pupae do not feed on anything and take about two days to develop to an adult.
The Aedes Aegypti mosquito is one of the most dangerous mosquitoes for the spreading of disease. This mosquito killed more people with Yellow Fever during the Spanish-American War than enemy fire.
The first step to protecting your family is to manage the space around your home to prevent the breeding of mosquitoes. Complete the below steps:
- Overturn empty flowerpots to prevent pooling.
- Maintain swimming pools to prevent stagnant, untreated water.
- Aerate birdbaths to prevent pooling.
- Clean gutters to prevent the buildup of particulate matter or blockings.
- Clean pet dishes every day.
- Continue to check your yard for any pooling of water in containers.
The second step is to protect your family when you leave the home. Follow these steps to prevent being bitten:
- Wear long sleeve shirts or pants to decrease the amount of skin available to mosquitoes to bite.
- Apply repellents such as DEET to the skin you cannot cover. Be careful to use DEET with a concentrate between 20 to 30%.
- Use a mosquito net over infant carriers, cribs or strollers.
Remember to check the screens on your windows; especially if you like to keep the windows open around your home.
The final step to protecting your family around your home is something that Tactical Mosquito Control can provide.
- Install a mosquito misting system around your home to kill the Yellow Fever Mosquito population at your home.
- Take part in our special yard treatment program that sterilizes the Aedes Albopictus(Asian Tiger Mosquito) and keeps it from breeding around your yard.