This blog is another collage of my posts to our Facebook group SW US Insects and Arachnids. Robyn Waayer chose the theme for this week. I was surprised how many very divers contributions I was able to pull out of my files. even leaving Robber Flies, Bee Flies and Syrphids out because they were represented well enough in other posts.
Hill-topping Cuterebra arizonae, Rodent Botfly
9-19-9 pima canyon, Catalinas, Pima Co, AZ
Jeff Boetner det.
'Females typically deposit eggs in the burrows and "runs" of rodent or rabbit hosts. A warm body passing by the eggs causes them to hatch almost instantly and the larvae glom onto the host. The larvae are subcutaneous (under the skin) parasites of the host. Their presence is easily detected as a tumor-like bulge, often in the throat or neck or flanks of the host. The larvae breathe by everting the anal spiracles out a hole (so they are oriented head-down inside the host). They feed on the flesh of the host, but only rarely does the host die as a result.' In some populations 80% of all rodents are parasitized. The drone of these big flies is louder than most insects' flying-sounds
Therevidae (Stiletto Flies) - genus Brachylinga Sabino Canyon, Pima Co, AZ USA 4/4/2012
Related to Robberflies, Stiletto Flies are less well known. But in dry, sandy areas they are probably ecologically rather important. Their larvae live in sandy soils as arthropod-predators
http://wwx.inhs.illinois.edu/research/therevid
Trichopoda indivisa, (Feather-legged Flies), Tachinidae
10-1-2012 Buenos Aires National Wildlife Preserve, Pima Co, AZ, USA
Small brightly-colored flies that frequent flowers. Sexes dimorphic (e.g. abdomen orange in males vs dark or dark-tipped in females). Calypters covered with yellow scales. Distinctive fringe on hind tibiae....
Life history of T. pennipes and T. plumipes in Swan & Papp
Mating may occur near nectar sources (P. Coin, pers. observation). Females hover over plants that attract their hosts (e.g., squash). Eggs are typically laid on underside of host. Only one larva per host will survive, though more than one egg may be laid on a given host. Newly hatched maggot bores into body of host and feeds on host's fluids for about two weeks. Eventually, it grows to almost the size of the host's body cavity. Maggot emerges at III instar, killing the host, and pupates in soil. Adult emerges in ~2 weeks. Second instar larva overwinters in the host's body.
Larval hosts are mostly true bugs (Heteroptera: Coreidae, Pentatomidae, Scutelleridae, Largidae), but also Dissosteira pictipennis (Acrididae), and a mantid (frm Bugguide.net info)
Nemomydas sp. - multiple Males and Female
Catalina State Park, Pima County, Arizona, USA
August 13, 2007
Mydas Flies are large, often wasp mimics with prominent, clubbed antennae. They move more slowly than many other flies. Larvae in decaying wood, soil, may be predatory
Neorhynchocephalus sackenii,
Nemestrinidae (Tangle-veined Flies)
Doug Yanega det.
in Copper Canyon south of the Huachucas, Cochise Co, AZ, Aug 2014
I was In Copper Canyon last August with Arthur V. Evans searching for beetles for his next beetle book, but these flies distracted with their constant loud buzz. Their larvae are parasites of grasshoppers, but some spp. also use scarab beetles as hosts. Supposedly rare in NA, but certainly very common then and there.
Odontoloxozus longicornis (Longhorn Cactus Fly)
Picture Rocks, Pima Co, AZ, March
Larvae in demposing cacti, a typical desert insect
Pseudotephritina Picture winged flies.
On mushrooms in Patagonia Creek Preserve (AZ, Santa Cruz Co) in October
Hermetia illucens (Black Soldier Fly)
Tucson
University Blv...
8-15-2011
Fascinating or not, this little bathroom guest with the suggestive scientific name is also a fly: Clogmia albipunctata (FilterFly)
Originally mostly tropical, now found in human habitats in much of North America. Larvae feed in water with decaying organic matter -- tree holes, stagnant ponds, drains, etc.
We tend to think of flies as those house flies that are a nuisance and can be a health threat even when they just land on our food. In this blog I've tried to show some of the extreme variety in looks and behavior that really makes flies (Diptera) one of the more interesting orders of insects.They are certainly among the most important ones to human economy. They transfer diseases, but they also sanitize the environment. They are important pollinators for many generalist plants. As parasites, they control other insect groups that compete with humans for food. Having a short generation sequence and few, nice big chromosomes, Drosophila Fruit Flies were among the most important models in genetic research. With big accessible eyes and large ganglia in their brains, Sarcophaga is used in electrophysiology research and teaching. The list goes on ...
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Cuterebra arizonae, Rodent Botfly |
9-19-9 pima canyon, Catalinas, Pima Co, AZ
Jeff Boetner det.
'Females typically deposit eggs in the burrows and "runs" of rodent or rabbit hosts. A warm body passing by the eggs causes them to hatch almost instantly and the larvae glom onto the host. The larvae are subcutaneous (under the skin) parasites of the host. Their presence is easily detected as a tumor-like bulge, often in the throat or neck or flanks of the host. The larvae breathe by everting the anal spiracles out a hole (so they are oriented head-down inside the host). They feed on the flesh of the host, but only rarely does the host die as a result.' In some populations 80% of all rodents are parasitized. The drone of these big flies is louder than most insects' flying-sounds
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Brachylinga sp. Therevidae (Stiletto Flies) |
Related to Robberflies, Stiletto Flies are less well known. But in dry, sandy areas they are probably ecologically rather important. Their larvae live in sandy soils as arthropod-predators
http://wwx.inhs.illinois.edu/research/therevid
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Trichopoda indivisa, (Feather-legged Flies), Tachinidae |
10-1-2012 Buenos Aires National Wildlife Preserve, Pima Co, AZ, USA
Small brightly-colored flies that frequent flowers. Sexes dimorphic (e.g. abdomen orange in males vs dark or dark-tipped in females). Calypters covered with yellow scales. Distinctive fringe on hind tibiae....
Life history of T. pennipes and T. plumipes in Swan & Papp
Mating may occur near nectar sources (P. Coin, pers. observation). Females hover over plants that attract their hosts (e.g., squash). Eggs are typically laid on underside of host. Only one larva per host will survive, though more than one egg may be laid on a given host. Newly hatched maggot bores into body of host and feeds on host's fluids for about two weeks. Eventually, it grows to almost the size of the host's body cavity. Maggot emerges at III instar, killing the host, and pupates in soil. Adult emerges in ~2 weeks. Second instar larva overwinters in the host's body.
Larval hosts are mostly true bugs (Heteroptera: Coreidae, Pentatomidae, Scutelleridae, Largidae), but also Dissosteira pictipennis (Acrididae), and a mantid (frm Bugguide.net info)
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Nemomydas sp |
Nemomydas sp. - multiple Males and Female
Catalina State Park, Pima County, Arizona, USA
August 13, 2007
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Mydas sp. |
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Neorhynchocephalus sackenii, Nemestrinidae (Tangle-veined Flies) |
Nemestrinidae (Tangle-veined Flies)
Doug Yanega det.
in Copper Canyon south of the Huachucas, Cochise Co, AZ, Aug 2014
I was In Copper Canyon last August with Arthur V. Evans searching for beetles for his next beetle book, but these flies distracted with their constant loud buzz. Their larvae are parasites of grasshoppers, but some spp. also use scarab beetles as hosts. Supposedly rare in NA, but certainly very common then and there.
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Odontoloxozus longicornis (Longhorn Cactus Fly) |
Picture Rocks, Pima Co, AZ, March
Larvae in demposing cacti, a typical desert insect
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Pseudotephritina sp. |
On mushrooms in Patagonia Creek Preserve (AZ, Santa Cruz Co) in October
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Hermetia illucens (Black Soldier Fly) |
Tucson
University Blv...
8-15-2011
Larvae live in compost, dung, rotting vegetation and are commercially distributed for composting. Therefore: Wide ranging in Western Hemisphere, also in Australasia, Africa, Japan, Europe.
Interesting: Very rarely, accidentally ingested larvae cause intestinal myiasis in humans and domestic animals.
Thecophora sp. Conopidae (Thick-headed Flies) Martin Hauser det.
Picture Rocks
4-12-2011
Interesting: Very rarely, accidentally ingested larvae cause intestinal myiasis in humans and domestic animals.
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Thecophora sp. Conopidae (Thick-headed Flies) |
Picture Rocks
4-12-2011
Female Conopids ambush bees or wasps. They attack their targets in mid-air, often tumble to the the ground with it, and drive an egg between the bee’s abdominal segments of the victim. The larva that hatches from the egg then feeds as an internal parasite of the host, eventually killing it in about ten to twelve days. The larva then pupates inside the hollow exoskeleton of its host. Eric had a blog about them: http://bugeric.blogspot.com/…/wasp-wednesday-not-wasp-ii.ht…
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Clogmia albipunctata (FilterFly) |
Originally mostly tropical, now found in human habitats in much of North America. Larvae feed in water with decaying organic matter -- tree holes, stagnant ponds, drains, etc.
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Flesh Fly (Sarcophagidae) on a dead dove. |