Yesterday, when I arrived for the weekly nature walk of the Friends of Sabino Canyon the temperature was in the fifties. Much too cold for mid-April morning in Tucson and too cold for most insects and lizards that I wanted to see. In addition, a fierce wind was howling down into the canyon from the Catalinas. The other naturalists decided to look mostly at plants, I guess because those can't hide from the elements. Two saguaros, one with an imposing crest, looked indeed positively defiant.
|Eastern Collared Lizard, who stayed hidden yesterday (Photo Ned Harris, April 2012)|
|View into Sabino Canyon from Esperero Trail|
|Ash-throated Flycatcher, who was out and about|
|Some of the hill-topping flies and butterflies|
At first I payed little attention to a big black fly that landed as if to bask in one of the sparse sunny spots because I mistook it for a Mexican Cactus Fly, a common syrphid. But then I heard a very deep basso buzz when the fly changed to another boulder, only about 5 m from the first. That sound is one of the loudest and deepest flight noises I've ever heard here in Arizona - not easy to forget. Through my new little Papillon binoculars I could also verify that the fly was not all black but had silvery grey flanks - a bot fly in the genus Cuterebra. (Later identified by Jeff Boettner as C. austeni)
|Rodent Bot Fly, Cuterebra austeni, Esperero Trail, Sabino Canyon, Pima County Arizona, April 2013|
|Deer Bot Fly, Cephenemyia jellisoni infects the alimentary tract of ungulates like white-tailed deer, mule deer, moose or elk. Photo by Philip Kline Pusch Peak, Catalina Mountains, Pima County, Arizona, March 2009|
|Pack rat with 2 nearly grown Cuterebra larvae Photo Jan Emmings|
|Cuterebra sp. larva ready to pupate found crossing Sabino Canyon Rd. on Feb. 22, 2011. Photo by Fred Heath|
|Rodent Bot Fly, Cuterebra sp., Pima Canyon, Catalina Mts. Pima County, Arizona, September 2009|
While feeding from the host subcutaneously for several weeks the larvae have to behave reasonably well. They seem to prevent inflammation even though they need to keep a hole in the host's skin open to be able to breath periodically. They probably have anti inflammatory and antibiotic capacities. I have two good friends who both got parasitized in Central America, are now in their eighties, and live and love to tell about it. If not removed prematurely, the larvae will eventually leave the host, drop to the ground and pupate. In time a new generation of mature adults will hatch. These big flies are born without mouth parts. From their time as maggots in the flesh, they are provisioned with enough energy reserves to survive for about 10 days, time enough to start the cycle again.
|Catching the redeye to Amhesrt, MA|
Here is a link to photos of the removal of a human bot fly larva (Peruvian Amazon)
Arthropoda (Arthropods) » Insecta (Insects) » Diptera (Flies) » Calyptratae » Oestroidea » Oestridae (Bot Flies) » Cuterebrinae (New World Skin Bot Flies) » Cuterebra (Rodent and Lagomorph Bot Flies)