Fly Day Friday: The Good Mosquito

Believe it or not, there is a mosquito species I look forward to seeing every year. You may think I'm crazy, but hear me out. There are at least three reasons to love elephant mosquitoes in the genus Toxorhynchites. They are pretty, beneficial in the larval stage, and do not bite as adults.

A male Elephant Mosquito

Elephant mosquitoes are also known as giant treehole mosquitoes, so you can sense a theme here. They are indeed large for mosquitoes, averaging about seven millimeters in body length. That does not include the mouthparts and antennae. Their long legs make them appear larger still. Why the name "elephant mosquito?" It may be a reference to the long, upcurved palps of the males, which suggest elephant tusks.

Notice the tusk-like palps (part of the mouthparts), and bushy antennae on this male.

There is no denying the beauty of our single North American species, Toxorhynchites rutilus. They are iridescent blue and purple, with silver and gold highlights, and white tips on the hind legs. It seems that no one photo captures all the colors all at once. Despite their brilliance, they are surprisingly cryptic in the dimming light of dusk, when they are most active (though they are considered day-fliers).

As their other name indicates, elephant mosquitoes breed mostly in water-filled treeholes. The larval stage, at least in later instars, is predatory on other aquatic insects, including....wait for it....the larvae of other mosquitoes. Yes, you heard that correctly, they are a natural biological control of the mosquito species that pose a threat to human health. The larvae are reddish in color, with a short anal siphon (bearing the spiracle that permits intake of air at the water surface), and a broad, black head with strong mandibles. There are four larval instars, an instar being the interval between molts.

The female Elephant Mosquito has straight palps, and simple bristle-like antennae.

The adult elephant mosquito has a distinctive proboscis, bent strongly downward near the middle of its length. Instead of using their beaks to draw blood from other animals, elephant mosquitoes of both sexes feed only on flower nectar. As flower visitors, they are also pollinators of wildflowers. Some other species in the genus may also feed on fruit juices, and honeydew (the sugary liquid waste of aphids, scale insects, and various planthoppers).

The female again, showing that long,sharply-curved proboscis.

Here in northeast Kansas, on the Missouri border, I have found Toxorhynchites rutilus only in late autumn, and only on the flowers of White Snakeroot. I have only seen them in our yard, in fact, but I am not usually exploring elsewhere as sunset approaches. The species ranges from the eastern half of Texas and Oklahoma diagonally northeast to southern Pennsylvania, Connecticut, and Delaware.

Can you tell which sex this one is?

There are roughly eighty species of Toxorhynchites, occuring mostly in tropical regions around the globe. Due to their unique appetite for other mosquitoes, they have been employed as biological controls for container-breeding mosquitoes in Japan, southeast Asia, the Caribbean, and in some cities in the United States.

Are you a new fan of elephant mosquitoes yet? If not, please see the resources and links below for additional information on the biology of these remarkable flies. Mosquitoes, like most insects, and people, defy neat categorizing as "bad" or "good." Entomology is a great place to learn lessons like that.

So handsome!

Sources: Alomar, Abdullah A. and Barry W. Alto. 2022. "Elephant Mosquito Toxorhynchites rutilus Coquillett, 1896 (Insecta: Diptera: Culicidae)," Ask IFAS EENY-787/IN1380. University of Florida.
Coin, Patrick, et al. 2004. "Species Toxorhynchites rutilus - Elephant Mosquito," Bugguide.net
Donald, Claire L., Padet Siriyasatien, and Alain Kohl. 2020. "Toxorhynchites Species: A Review of Current Knowledge," Insects 11(11): 747.
McAlister, Erica. 2017. The Secret Life of Flies. Buffalo: Firefly Books. 248 pp.
Ricciuti, Ed. 2019. "Meet the Mosquito With a Big Appetite - for Other Mosquitoes," Entomology Today.

First Night of Blacklighting

Since I posted about my last night of blacklighting last year, it seems only fitting that I post about the first night of blacklighting this year. We had an unseasonably warm and humid night on March 31, 2024, so I put up a sheet and light in our fenced-in back yard here in Leavenworth, Kansas, USA. The effort turned up a handful of nice moths, and a couple of surprises.

Birch Dagger moth

A lovely and surprising moth was a freshly-minted Birch Dagger moth, Acronicta betulae. It looked like the front wings were made of two layers. Striking! This is a widespread eastern U.S. species, but eastern Kansas is at the western fringe of its range. We also do not have any River Birch, the host tree for the caterpillar, to my knowledge, so perhaps it is feeding on a different tree here.

Intractable Quaker moth

Another kind of owlet moth in the family Noctuidae that showed up was the Intractable Quaker. Ok, who makes up these names? The caterpillar of this moth is more straightforward: Four-lined Green Fruitworm. The scientific name of the species is Kocakina fidelis, but known formerly as Himella fidelis. This is another early-appearing eastern North American moth. The caterpillar stage feeds mostly on the leaves of oak, elm, and flowering crabapple, but is also known from hickory and cherry.

Distinct Quaker moth

The final noctuid of the night was the Distinct Quaker, Achatia distincta. It is a spring species ranging mostly east of the Great Plains, but with scattered records farther west. The caterpillar is a generalist feeder on most common deciduous trees, plus grape.

An expected species was an owlet moth in the family Erebidae, the Forage Looper, Caenurgina erechtea. It is abundant here locally, but is common throughout the U.S. and Canada. Caterpillars feed on grasses, clover, and alfalfa. Walking through your lawn will flush these moths during the day, especially if it has beeen awhile since you mowed.

Common Gray moth(?) male

One geometer moth was tucked in a fold in the sheet: what I believe to be a Common Gray, Anavitrinella pampinaria. The lack of clear markings makes identification even more difficult than usual, but the early spring flight period is typical. This is another widespread species across the continent. The super-slender caterpillars (inchworms) are known to feed on clover, ash, elm, willow, pear, and apple.

Lucerne Moth

One moth of the family Crambidae flew to the edge of the sheet. The Lucerne Moth, Nomophila nearctica, is found nearly everywhere in North America, farther north in the west. Its narrow silhouette makes this moth one of the easiest to recognize. The caterpillars feed on a wide variety of grasses and sprawlilng legumes like clover and alfalfa.

Smaller moths were more common, including a single individual of the Red-banded Leafroller Moth, Argyrotaenia velutinana. This species of the family Tortricidae is common east of the Rocky Mountains, from Louisiana to Saskatchewan. There is hardly any foliage and fruit that is not on the menu for the caterpillar stage, and it is an occasional pest in apple orchards.

Unidentified tortricid moth

Maple Twig Borer Moth

A couple of other tortricids defy identification, and I am rusty at photography after the winter hiatus. Wait, one of them was confirmed as the Maple Twig Borer Moth, Proteoteras aesculana. As the name suggests, it occurs where maple trees are found, and the caterpillar stage tunnels in the twigs and petioles, and seeds of the host tree.

Twirler moth, genus Chinodes?

Finally, there was a solitary little twirler moth, family Gelechiidae, that I figure is one of the 190 North American species of Chinodes.

Ichneumon wasp, Ophion sp.

A bit surprising was the diversity of wasps present at the blacklight. Ichneumonid wasps in the genus Ophion are regular visitors, as they are nocturnal, but a beautiful Rhyssella nitida also showed up.

Ichneumon wasp, Rhyssella nitida

This is a diurnal insect. The female uses her long ovipositor to drill into logs and dead trees to reach the larva of its host, wood-wasps in the genus Xiphydria. She lays a single egg on the grub, and the larva that hatches feeds as an external parasitoid, eventually killing the wood-wasp larva.

Braconid wasp

Braconid wasp, Phanerotoma sp?

Braconid wasp

Wasps in the family Braconidae, closely related to ichneumons, also flew in. They are almost impossible to identify from images of living specimens, but their diversity and abundance is encouraging in an age of insect decline.

A particularly attractive non-biting midge, tribe Macropelopiini

Typical non-biting midge, tribe Chironomini

As expected, flies were the most diverse insects on the sheet. Non-biting midges in the family Chironomidae can be found almost year round. They are usually asssumed to be mosquitoes, and they are certainly mosquito-like in appearance, but totally harmless. Most live in aquatic habitats in the larval stage, where they are usually scavengers.

One of the larger gall midges I've seen

Early spring is the time for gall midges in the family Cecidomyiidae. These small, delicate flies are recognized in part by the reduced number of veins in their wings, and their usually long antennae. They are tiny enough that they can account for the most commonly found insects indoors, accumulating in light fixtures and on windowsills.

Fungus gnat

Fungus gnats are also springtime flies, of the family Mycetophilidae. They look like mosquitoes, too, but their legs usually sport long spines, at least at the tip of the tibia segment. The larvae of many species occur in mushrooms, and are identified by their black heads. The adults of some species pollinate the flowers of Jack-in-the-Pulpit, but frequently die after becoming trapped in the corolla.

Leaf miner fly, Cerodontha sp.

More obviously fly-like were little leaf miner flies, in the genus Cerodontha, family Agromyzidae. Their larvae bore between the layers of grassblades, and leaves of sedges and rushes. We have both grasses and sedges in our back yard, so that tracks. Identifying insects is often a matter of putting different clues together and seeing what shakes out.

Shiny Blue Blow Fly, Cynomya cadaverina

A big, bumbling blow fly bounced around the light, too, and it was difficult to get an image of it. I think it was a Cynomya cadaverina. No dead bodies in the backyard, so its presence is a mystery.

Birch Catkin Bug

The other mystery was the appearance of a Birch Catkin Bug, Kleidocerys resedae, a tiny member of the seed bug family Lygaeidae. As in the case of the Birch Dagger Moth, the absence of birch trees raises questions about what these bugs are eating.

All thirty insects that I documented can be found on iNaturalist here. It has been windy and cooler this last week, so I'm not sure when I'll put the light out again, but I look forward to doing so. Weather permitting, I will at least try again during the City Nature Challenge, April 26-29. Check and see if your town is registered for the event. Happy bugwatching to you in any event.

Strange Flies on a Fish Carcass

Spring has been dragging her heels here in northeast Kansas, USA, but my partner and I managed a brief outing to take advantage of a certifiably warm and sunny day this past Saturday. Finally, there were a few insects to be seen, even if they were mostly non-biting midges, a few other flies, one butterfly, and several Eastern Boxelder Bugs. Heidi spotted the remains of a large fish just off the trail, and I noticed some small, unusual flies dashing over the head of the dead piscine. I managed a few images, and saw that I had something unfamiliar and pretty interesting.

One female (top, left) and two male waltzing flies

The location of our short hike was the Mill Creek Streamway Park in Johnson County, Kansas, north of Shawnee Mission Park. We were on Nelson Island in the Kansas River for most of the time, and that is where we found the fish remains. The overstory was mostly cottonwood trees, the understory just beginning to green up.

A blow fly and at least two waltzing flies

There were the obligatory blow flies on the fish, too. I suspect the deep metallic blue insects were either Phormia or Protophormia. Without collecting specimens, fly identification is problematic. It comes down to patterns of setae, the color of thoracid spiracles, and other miniscule characters that are not usually visible in mere photographs of wild, mostly moving targets.

The smaller flies were another matter. They were so unique that once I returned home I was immediately able to identify them to species. More importantly, I learned about their bizarre behavior. About twice the size of your average kitchen-inhabiting "fruit fly," Drosophila sp., these flies were slender and long-legged, the better for running around and chasing each other, as was apparent in the field.

Male waltzing fly

Surprisingly, my hunch that they were members of the "skipper flies" family Piophilidae was correct. The most famous members of the family are the cheese skippers, named for the "jumping" maggots that infest rancid cheese, "skipping" away from danger by grasping their rear end in their mouths and suddenly releasing it, catapulting themselves vertically and horizontally. As a whole, the larvae of most species feed on decomposing fatty tissues in carrion, often after the corpse begins drying out.

Female (top) and male waltzing flies

The flies I had been observing were "waltzing flies" of the species Prochyliza xanthostoma. Their most distinguishing aspect is the sexual dimorphism between males and females. Males have greatly elongated heads, with a torpedo-shaped face and remarkably long atennae originating from the tip of the cone. Females are more....demure, or at least less comical in appareance, with a head of more normal dimensions.

Why the long face on the males? Stephen A. Marshall, in his epic tome Flies: The Natural History and Diversity of Diptera, explains:

"One of my favorite piophilines is Prochyliza xanthostoma, a Nearctic species that appears in abundance in early spring when melting snow exposes the carcasses of winter-killed animals. Males of P. xanthostoma have long antennae and a greatly elongated head that is used in ritual male-male battles for territory, during which these striking insects stand on their hind legs and engage in vigorous head-butting contests."

Dr. Erica McAlister, in her fascinating book The Secret Life of Flies, also notes the ferocity of these sparring matches:

"The males in another of the group, the waltzing fly, Prochyliza xanthostoma, have quite wonderful heads - almost conical in shape with very large and thick antennae - and they feed on animal carcasses. As their name suggests the males dance to woo the females. But they also have to defend their territories (carcasses) from other males and can have the most amazing fist fights - they really reign down punches on each other.

A female ignoring two competing males

I am now regretting not to have taken a video or two while I was there, though Heidi had long since made her way far ahead of me on the trail. Should I encounter waltzing flies again, I won't make that error of omission. Meanwhile, you might want to search for them. The species occurs over most of North America, especially the eastern half of the continent. If you are sufficiently intrigued, this Wikipedia article goes into extraordinary detail about the behavior and biology of the species.

Fungus Party-y-y!

Sometimes, with luck, you stumble upon a wonderful circumstance of insect abundance. My partner, Heidi, did so this past Saturday afternoon, September 17, along a trail through Wyandotte County Lake Park, Kansas, USA. She happened to notice a thick mass of mushrooms at the base of a tree. It was literally crawling with insects.

Everybody on the dance floor!

The fungus in question may be a species of “oyster mushroom” in the genus Pleurotus, according to Ben Sikes at the University of Kansas, and with the Kansas Biological Survey. He was kind enough to offer an opinion on my photo of it on iNaturalist. At least some species are fit for human consumption, too, but please do not forage without expert guidance, at least initially. Your experiment in wild culinary arts could end abruptly and permanently if you do not know exactly which mycological fruiting bodies to avoid.

"Get down to it....get down to it...."

Insects, on the other hand, do not seem to care, especially the many varieties of beetles that are collectively known as fungus beetles. There are pleasing fungus beetles (family Erotylidae). There are handsome fungus beetles (Endomychidae), hairy fungus beetles (Mycetophagidae), tooth-necked fungus beetles (Derodontidae), silken fungus beetles (Cryptophagidae), polypore fungus beetles (Tetratomidae), cryptic fungus beetles (Archeocrypticidae), minute tree-fungus beetles (Ciidae), and several genera of darkling beetles (Tenebrionidae) that are found almost exclusively on or in fungi, including woody shelf fungi. I may be forgetting some….

Triplax thoracica, but there may have been another species with a dusky or black belly instead of an orange underside.

The most abundant insect on this particular mushroom cluster is probably a pleasing fungus beetle, Triplax thoracica. That genus, certainly, but that species apparently loves oyster mushrooms. It occurs across the eastern half of the U.S. and adjacent Canada. At only 3-5.6 millimeters in length, they are difficult to spot as individuals, but there were dozens flying in, flying out, and running about.

Uh, oh [abrupt, scratched record sound].

In a prehistoric analogy, Triplax are the herd of plant feeders. Sure enough, there were vicious carnivores prowling through the gills and over the caps of the mushrooms.

Sharp dresser, anyway.

A sleek, serpentine, black rove beetle with metallic blue-green elytra (wing covers) popped into view periodically. Meet Philonthus caeruleipennis, 12-15 millimeters long. Were it a vertebrate, it would no doubt be a weasel, mink, ferret, or other mustelid. It is transcontinental in Canada, but occurs only in the northeast quarter of the U.S. It also occurs in Europe.

Pull the fire alarm! Call 9-1-1!

The equivalent of Tyranosaurus rex in this micro-scenario would be the Brown Rove Beetle, Platydracus maculosus. Measuring 22-35 millimeters, it dwarfs its prey, which in this case was the Triplax fungus beetles.

Serial killer making mincemeat of partygoers.

By now, oblivious to the monsters among them, the Triplax party was becoming something of an orgy, with love trains of males following females. It was quite amusing.

Gettin' busy.

Some of the fungus beetles also had passengers in the form of phoretic mites. The mites, which are probably “mesostigs” in the order Mesostigmata, cause no harm to the beetles. Instead of being parasitic, the mites are hitchhikers, using the beetles as transport to a location where they can feed on insect eggs or other tiny prey.

Mites being a little voyeuristic....

Along with the beetles were pomace flies, family Drosophilidae. These are the “fruit flies” you see in your kitchen around overripe fruit, fermented beverages, and other foods. Drosophilids sare surprisingly diverse, and a good variety can be found around rotting fungi “in the wild.”

Pomace fly disappointed that the mushroom is not spoiling already....

The latecomer to the party was a worker Tennessee Spine-waisted Ant, Aphaenogaster tennesseensis. She was simply looking for dead or injured insects she could take back to her colony to feed her larval sisters.

"Just passing through!

At last, it was time for me to say farewell. Heidi had already progressed down the trail by about fifty yards.

"I'm blowin' this fruit stand!"

Now is a perfect time to go out looking for mushrooms and their associated insects. We left these mushrooms alone, but sometimes it is necessary to tear apart the fungus to find insects. It is best to do so over a white enamel pan, or some other kind of tray so that it catches the insects falling out. Be quick to grab the rove beetles before they take flight. If you do know your mushrooms, then bonus! You can take uninfested specimens to the kitchen instead of the lab. Enjoy your autumn no matter what you do.

Nom-nom-nom-nom....

Sources: Rhine, Lyndzee. 2020. A Pocket Guide to Common Kansas Mushrooms. Wichita: Great Plains Nature Center. 69 pp.
Evans, Arthur V. 2014. Beetles of Eastern North America. Princeton, New Jersey: Princeton University Press. 560 pp.

Fly Day Friday: Biting Midges, No-See-Ums, Punkies

The list of aliases for the biting midges of the fly family Ceratopogonidae is seemingly endless, but most are apt descriptions of how tiny these insects are. I suppose I could emphasize their diminutive size by not illustrating this post at all, and leaving their appearance to your imagination....These flies certainly stretch the limits of my Canon PowerShot SX50 (and more recently SX70), so I encourage you to visit other photo resources to see the insects' true majesty.

Adult female Culicoides sp.from Colorado, USA.

Were it not for the few species of biting midges in the genus Culicoides that habitually bite humans, we might know little about them at all, aside from those that bite livestock. The majority of ceratopogonids apparently feed mostly on the hemolymph (blood) of other insects, believe it or not.

Biting midges feeding on the hemolymph (blood) of an Arizona Sister butterfly in the Huachucha Mountains of Arizona, USA

Only the females take blood meals, and in some species the females have atrophied mouthparts and do not feed on blood. Both sexes feed on nectar and other sugary liquids as well, to fuel their flights. There are at least 39 genera, with over 600 species, of Ceratopoginidae in North America north of Mexico.

© Judy Semroc

I was prompted to finally do a post about no-see-ums, in part, by an e-mail I received from my friend Judy Semroc, an accomplished wildlife photographer. She sent me images of peculiar "larvae" around the nostrils of a snapping turtle. It wasn't until the final close-up image that I was able to discern that the creatures were actually adult female biting midges, some so engorged with blood that they looked more like mites.

© Judy Semrock

Not all ceratopogonids are that small. They collectively range from one to six millimeters in body length. They are not always easy to tell apart from other families of non-biting midges, but with a little practice one can often discern the "long face" that includes a short proboscis and associated palps.

This biting midge has killed a non-biting midge in Wisconsin, USA

No-see-ums can be more than a mere nuisance. Some are known to transmit disease-causing microbes to humans and livestock. They are a principal vector of bluetongue, a virus which afflicts cattle and sheep.

In this specimen from Colorado, USA, you can see the proboscis and palps.

There is, however, at least one redeeming member of the family. A species in the genus Forcipomyia is the sole pollinator of cacao trees, the plant from which we get chocolate. Unfortunately, when tropical forests are turned into cacao plantations, the tiny flies lose the humid conditions and moist soil needed to complete their life cycle.

The life cycle of ceratopogonids usually revolves around aquatic or semi-aquatic habitats, or excessively moist conditions in otherwise dry habitats. Larvae may live under bark of decaying logs, in mosses, treeholes, sap flows, or soil. There, most feed on floral debris, algae, or fungi. Larvae in fully aquatic habitats are mostly or exclusively predatory on other small organisms.

Male biting midges, like this one from Illinois, USA, often fold down the setae on their antennae, giving them the appearance of having a mustache.

Adult male midges of many species form aerial swarms over a prominent object or landmark, to attract the attention of females. The plumose (feather-like) antennae of males function as "ears," tuned to the wingbeat frequency of approaching females. Mating usually takes place while airborne, though some species alight to copulate.

Clinohelea bimaculata, Leavenworth, Kansas, USA

Another encounter that fueled my curiosity about ceratopogonids happened just yesterday. I spotted what I initially thought was a small, skinny mirid plant bug on the surface of a leaf in our back yard. I had serious difficulty getting an in-focus image with any detail whatsoever. Reviewing the images it became clear it was not even a true bug. On a hunch I explored Bugguide.net for ornate punkies. Lo-and-behold, I found a match: Clinohelea bimaculata. It will be a state record for Kansas for both Bugguide and iNaturalist, provided I have identified it correctly.

Oh, my, I think it has prehensile "toes" (tarsal claws)!

The preceding is at best a snapshot of a highly diverse and complicated family of flies. Much is known, especially about species of economic and public health importance, but there remains much to learn.

Sources: McAlister, Erica. 2017. The Secret Life of Flies. Richmond Hill, Ontario: Firefly Books. 248 pp.
McAlpine, J.F., et al. 1981. Manual of Nearctic Diptera, Volume 1. Ottawa, Ontario: Agriculture Canada. 674 pp.
Bugguide.net
a href=http://campus.belmont.edu/cienews/cie.html>The Ceratopogonid Web Page.