KrakenQueen
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I'm not sure if this has been discussed in the past, but I figured JUST in case, I would bring it up.
Cricket Gnats, AKA parasitic tachinid fly Ormia.
I observed mass die-offs with my crickets over a period of two years and always noticed these tiny, speedy little gnats (flies) scuttling about the containers where the crix were located. At the time, I never took any time to figure out why they were there- I just assumed they were normal gnats. I was wrong!
Months ago I took out several crickets showing odd signs, rubbing near the spiracles, back legs not working or splaying, swollen bodies and darkening of coloration. So, I took a few of these crickets and placed them in a plastic ziplock bag. A day after they died, the larva emerged, pupated and eventually became those exact same gnats/flies that would be found in the tanks. YUCK. What happens is the fly drops its eggs near the spiracle, which hatch and the larvae crawl into the spiracle and make their homes inside their cricket host, killing it.
These buggers are the worst: (Wikipedia)
"In 1975, Dr. William H. Cade discovered that the parasitic tachinid fly Ormia ochracea is attracted to the song of the male cricket, and uses it to locate the male in order to deposit her larvae on him. It was the first example of a natural enemy that locates its host or prey using the mating signal[2]. Since then, many species of crickets have been found to be carrying the same parasitic fly, or related species. In response, a mutation leaving males unable to chirp was observed amongst a population of field crickets on the Hawaiian island of Kauai."
http://en.wikipedia.org/wiki/Ormia
http://en.wikipedia.org/wiki/Ormia_ochracea
http://evolution.berkeley.edu/evolibrary/news/061201_quietcrickets
"Ormia ochracea is a small yellow fly, a parasitoid of crickets. It is notable because of its exceptionally acute directional hearing. The female is attracted by the song of the male cricket and deposits larvae on or around him, as was discovered in 1975 by the zoologist William H. Cade[1]. The fly is found throughout the southern the US and into Mexico, though its exact range is not known.
The mating call of the male field cricket is used by Ormia ochracea in locating the cricket. Once a female fly finds a host (male cricket) she deposits a larva which then quickly burrows into the host, emerging about 7 - 10 days later, killing the host. Flies have been observed responding to a variety of cricket songs[2], but seem to be limited to the genus Gryllidae.
Ormia ochracea has become a model organism in sound localization experiments because of its unique "ears", which are complex structures inside the fly's prothorax near the bases of their front legs. The animal is too small for the time difference of sound arriving at the two ears to be calculated in the usual way, yet it can determine the direction of sound sources with exquisite precision. The tympanic membranes of opposite ears are directly connected mechanically, allowing resolution of nanosecond time differences[3][4] and requiring a new neural coding strategy.[5] Efforts to build directional microphones based on the structure of the fly's ear are underway."
Unfortunately a lot of cricket breeders are shipping these crickets out with this parasitic insect- now, as far as I am aware the gnats aren't a problem for our pets. They're a major pest for both crickets and their relatives the roach. I lost a great deal of my roaches and crickets to the Ormia.
I managed to eventually wipe them out by culling all freshly dead and suspect crickets and roaches in the toilet. Anytime I saw the gnats I'd squash them, they tend to prefer to scuttle along the tank rather than fly.
Hope this is useful to the unaware!
Cricket Gnats, AKA parasitic tachinid fly Ormia.
I observed mass die-offs with my crickets over a period of two years and always noticed these tiny, speedy little gnats (flies) scuttling about the containers where the crix were located. At the time, I never took any time to figure out why they were there- I just assumed they were normal gnats. I was wrong!
Months ago I took out several crickets showing odd signs, rubbing near the spiracles, back legs not working or splaying, swollen bodies and darkening of coloration. So, I took a few of these crickets and placed them in a plastic ziplock bag. A day after they died, the larva emerged, pupated and eventually became those exact same gnats/flies that would be found in the tanks. YUCK. What happens is the fly drops its eggs near the spiracle, which hatch and the larvae crawl into the spiracle and make their homes inside their cricket host, killing it.
These buggers are the worst: (Wikipedia)
"In 1975, Dr. William H. Cade discovered that the parasitic tachinid fly Ormia ochracea is attracted to the song of the male cricket, and uses it to locate the male in order to deposit her larvae on him. It was the first example of a natural enemy that locates its host or prey using the mating signal[2]. Since then, many species of crickets have been found to be carrying the same parasitic fly, or related species. In response, a mutation leaving males unable to chirp was observed amongst a population of field crickets on the Hawaiian island of Kauai."
http://en.wikipedia.org/wiki/Ormia
http://en.wikipedia.org/wiki/Ormia_ochracea
http://evolution.berkeley.edu/evolibrary/news/061201_quietcrickets
"Ormia ochracea is a small yellow fly, a parasitoid of crickets. It is notable because of its exceptionally acute directional hearing. The female is attracted by the song of the male cricket and deposits larvae on or around him, as was discovered in 1975 by the zoologist William H. Cade[1]. The fly is found throughout the southern the US and into Mexico, though its exact range is not known.
The mating call of the male field cricket is used by Ormia ochracea in locating the cricket. Once a female fly finds a host (male cricket) she deposits a larva which then quickly burrows into the host, emerging about 7 - 10 days later, killing the host. Flies have been observed responding to a variety of cricket songs[2], but seem to be limited to the genus Gryllidae.
Ormia ochracea has become a model organism in sound localization experiments because of its unique "ears", which are complex structures inside the fly's prothorax near the bases of their front legs. The animal is too small for the time difference of sound arriving at the two ears to be calculated in the usual way, yet it can determine the direction of sound sources with exquisite precision. The tympanic membranes of opposite ears are directly connected mechanically, allowing resolution of nanosecond time differences[3][4] and requiring a new neural coding strategy.[5] Efforts to build directional microphones based on the structure of the fly's ear are underway."
Unfortunately a lot of cricket breeders are shipping these crickets out with this parasitic insect- now, as far as I am aware the gnats aren't a problem for our pets. They're a major pest for both crickets and their relatives the roach. I lost a great deal of my roaches and crickets to the Ormia.
I managed to eventually wipe them out by culling all freshly dead and suspect crickets and roaches in the toilet. Anytime I saw the gnats I'd squash them, they tend to prefer to scuttle along the tank rather than fly.
Hope this is useful to the unaware!
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