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Mosquito of the Month: Aedes pullatus - the Alpine Snowmelt Mosquito

Posted by The VDCI Team on Mar 30, 2016 12:07:48 PM
Written By Michael “Doc” Weissmann, Ph.D., Chief Entomologist
 
Aedes_pullatus_from_Carpenter__LaCasse_1955-2.jpgHigh in the Rocky Mountains, under the snow and ice, eggs that were laid by mosquitoes last summer lay dormant, waiting for spring. As soon as the ice becomes liquid, the first of the eggs will hatch. 

Known as the snowmelt mosquitoes, these species have a short season in which to grow. In order to get a head start, the larvae are adapted to survive in very cold water, including snowmelt ponds and overflow pools from frigid mountain streams. The cold water slows down their metabolism as well as their development into a flying, biting adult mosquito, which can take several weeks.

One of the most widespread, and arguably most beautiful of these cold-adapted species, is the Alpine Snowmelt Mosquito, Aedes pullatus. This mosquito is often abundant throughout the summer in mountainous areas of western North America, Europe, and Asia. They occur mainly in higher elevations, although also found less commonly as low as sea level in the colder northern latitudes.
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Topics: Mosquito of the Month Series

Mosquito of the Month: Sabethes cyaneus – the Paddle-legged Beauty

Posted by Daniel Markowski, Ph. D. on Feb 4, 2016 11:03:00 AM
Written By Michael “Doc” Weissmann, Ph.D., Chief Entomologist
 
Valentine’s season is upon us -- whether we like it or not, our obsession with courtship seems to take center stage. Indoor creatures, like humans, are not deterred by the winter; but, for most insects in the Northern Hemisphere, it is still too cold outside for mating. Meanwhile, in the tropics, many species are active throughout the year. Outside of a geeky entomology laboratory, it is quite rare for a discussion about courtship to include any mention of mosquitoes; the vast majority of species don’t display any behavioral patterns complex enough to even qualify for the term. For most mosquitoes, mating is a fast and haphazard occurrence with swarms of males circling around and waiting for the sound of female wing-beats. Once detected, the male rushes after the female and immediately attempts copulation mid-air without so much as a “how do you do?” – this is not courtship. 

paddle_mos.jpgThere is one notable exception, the paddle-legged beauty, Sabethes cyaneus. This tropical forest species lay their eggs in shaded natural and artificial containers such as tree-holes, bamboo hollows, and even fallen banana leaves filled with rainwater. Sabethes larvae develop in these small source pools and feed on bacteria, algae, and other organic material. The beautiful adult Sabethes mosquitoes are usually encountered in close proximity to the small habitats of their youth.
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Topics: Mosquito of the Month Series

Mosquito of the Month: Aedes albopictus – the Asian Tiger Mosquito

Posted by Daniel Markowski, Ph. D. on Jan 7, 2016 9:04:46 AM
Written By Michael “Doc” Weissmann, Ph.D., Chief Entomologist
 
Asian TigerAs if we didn’t have enough mosquitoes in the USA to deal with already, someone had to go and import one from across the ocean.  Great – thanks a lot!.  
 
Nobody is really sure exactly when the first of these invaders arrived into the USA , but the original recognized North American specimen of the Asian Tiger Mosquito, Aedes albopictus, was collected in June 1983 from a cemetery in Memphis, Tennessee. The species has since become one of the most challenging mosquitoes to control, and brings with it a host of other disease-related challenges.   
So what makes this invader such a challenge for mosquito control programs? While most mosquitoes are vampire-like in their avoidance of the sun, waiting until after sunset to seek a blood meal, the Asian Tiger Mosquito can more likely be found actively biting during the daytime in full sunlight. That’s not good. Most modern adult mosquito control occurs after sunset in order to avoid negatively impacting day-flying insects like bees, butterflies, and other popular pollinators. Any pesticides sprayed at night are dissipated by the time the Asian Tiger Mosquitoes take to the wing the next day.   
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Topics: Mosquito of the Month Series

Mosquito of the Month: Culex pipiens - Northern House Mosquito

Posted by Daniel Markowski, Ph. D. on Dec 2, 2015 10:06:38 AM
Written By Michael “Doc” Weissmann, Ph.D., Chief Entomologist
 
Culex_Pipiens.jpgIt is winter and all the mosquitoes have died, right? Well, not exactly.  
 
While many species of mosquitoes laid eggs last summer or fall and then died, others including the Northern House Mosquito, Culex pipiens, overwinter as an adult, waiting until next spring to lay their eggs. Throughout temperate zones of North America, Europe, and Asia, there may be snow on the ground outside, but these mosquitoes can still be found if one knows where to look for them.  
 
In late summer and early autumn, these mosquitoes forego the blood meals and instead fuel up on nectar or other sugary fluids, storing it as fat in their body. Before human construction, they likely spent the winter in caves or hollow trees – protected from the worst of the winter elements.  In such shelters they remain warm enough to keep from freezing to death, but cool enough that they don’t burn up all of their fat reserves before spring.  Humans have provided them with additional safe winter hiding places, including culverts, barns, stables, garages, basements, and sheds.  Some populations have even developed the ability to be active year-round in warmer structures such as the London Underground railway system, where they were notorious for attacking the city’s citizens who were seeking shelter in the subway tunnels during bombing air-raids of World War II.  If you find a mosquito flying around your garage on a warmer-than-normal December day, or resting on the wall of your shed in the middle of winter, it is likely this species.  
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Topics: Mosquito of the Month Series

Mosquito of The Month Series, General Overview

Posted by Daniel Markowski, Ph. D. on Nov 4, 2015 9:27:00 AM
Written By Michael “Doc” Weissmann, Ph.D., Chief Entomologist
 
mosquito2“Seriously?  You get paid to identify mosquitoes?  How many kinds of mosquitoes are there?” 
 
Years ago when I started working in a mosquito control surveillance laboratory, some of my non-scientific relatives and friends were surprised to hear that there were so many different species of mosquitoes, and that there was a need to tell one kind of mosquito from another.  In fact, according to the Walter Reed Biosystematics Unit/Smithsonian Institution, there are nearly 3,300 named mosquito species currently recognized worldwide.   In the United States alone, more than 175 species have been recorded. 
 
With so many species of mosquitoes discovered so far, it would take almost 275 years to run out of species to write about for a Mosquito of the Month blog posting.  However, for many mosquitoes, we only have a name, physical description, and location where they have been discovered – little or nothing is known about their biology, natural history, and behavior.  A relatively few species have been studied in more detail, yet for those species that we do know more about, mosquitoes turn out to be a highly diverse and fascinating group.  
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Topics: Mosquito of the Month Series