Wednesday, January 19, 2022

Winter Stoneflies


Tonya Smith sent this on winter stoneflies she filmed, seen racing over the ground in this video, during a hike at Shoal Creek.  I haven't come across these hearty insects that go out on a jog during freezing weather.  One reason for this, as the late naturalist H.B. Noel Hynes suggested, is that they are "most abundant early in the season before the average entomologist has emerged from hibernation."

Winter hike - Click to enlarge
Stoneflies are in the order Plecoptera.  The winter stoneflies have their calendar completely reversed from other macroinvertebrates living in our streams.  The nymphs spend much of their life in the hyporrheic zone, the water flowing beneath the rocks and gravel bars on the bottom of streams with the adults emerging in late winter.

The critters Tonya found are out looking for love when they emerged from their final molt.  Although equipped with wings, many species prefer walking along the edge of the water.  In Tonya's video they are running.  

The males tap their abdomen against the surface and if the female is in the mood she will tap back.  After that.....well this is a family blog but you know what happens. Then the female returns to the water to deposit her fertilized eggs.

Shortly after hatching, the nymphs essentially hibernate through the spring and summer.  In the fall they become active again, molting between 10-24 times before emerging as a winged adult.  The nymphs of most species are grazers, going through multiple molts while scraping aquatic vegetation or decaying organic matter from the stream bed.   

Like some frogs and other winterized insect species, the secret to their success is antifreeze in the form of glycerol and a mix of proteins and sugars.  This prevents the water in their bodies from forming ice crystals.  I wonder if the reason Tonya's specimens below are running is to keep warm.

Wednesday, December 15, 2021

Life in a Looper


Last month, Barb put some cuttings from her Swedish ivy, Plectranthus australis, in a vase on top of our piano. The plant is in the Lamiaceae or mint family. A few days later we found frass all around the base and spotted this looper caterpillar crawling along the leaves. 

We identified it as a soybean looper, Chrysodeixis includens.  It is found all over the western hemisphere and even the Galapagos.  It is a soybean pest but its diet includes a number of plant families including Lamiaceae above.


 
A few days later it had wrapped up a leaf in silk and formed a pupa.  We sealed the pupa in a baby food jar with a dampened little piece of paper towel to raise the moth for confirmation. When we returned to town a week later we found the leaf/pupa case seemingly intact and the jar filled with 200-300 little 1.5 mm winged creatures.   
Our best guess is these are parasitoid wasps, probably in the superfamily Chalcidae.

The silk case around the leaf had these wasps on the outside but none inside or on the pupa as seen below. Without a microscope I wasn't able to get any better photographs than this one. I kept the jar of wasps until Barb ruled that the household Statute of Limitations had run out and the dead bodies were committed to the kitchen drain.

There are over 22,500 known species of Chalcid wasps (who keeps track of them?) and most are under 3mm in length, the smallest being 0.14 mm! Most are parasitoids of insect species ranging from lepidoptera (butterflies and moths), flies, bugs and beetles, and even a few spiders. Ours probably emerged from the caterpillar pupa although I can't see the exit holes and none are inside the silk web.

Wasps all outside the silk enclosure

I am holding on to the pupa until spring in the unlikely possibility it wasn't the source of the wasps. Don't tell Barb.

Sunday, December 12, 2021

Long-legged Fly


Last May I got this photograph of a long-legged fly from Courtney Reece of the WOLF School.  We now have "research grade" confirmation on INaturalist that it is Condylostylus longicornis, possibly the most wide spread species in its genus, found from the US down to Paraguay and even Polynesia!

Head on - Ken Schneider CC
Long-legged flies range in size from 1 to 9 mm and are usually a shining metallic color ranging from green to blue to bronze. They are generally characterized by their slender bodies and long legs.

They are commonly found in moist woodland areas.  Larvae develop in wet to dry soil and pupate in cocoons made up of soil particles cemented together. The larvae are predators, feeding on soil or bark-dwelling invertebrates.  Adults mate after elaborate and unique behavior, involving the males displaying their legs to the female.  Bugguide

Long-legged flies belong to the family Dolichopodidae (try saying that three times rapidly!) which has thousands of species worldwide.  Typically they have large, prominent eyes and a metallic cast to their appearance.

"Long-legged flies (Figure 1) are small (1-9 mm), but easy to recognize because of their metallic green, blue or gold coloration, slender body shape, and not surprisingly, rather long legs! Often you can find them scurrying about on vegetation in the sunlight during the day. They are excellent fliers, but usually run or fly short distances from leaf to leaf when disturbed, making them a lot of fun to observe in your own backyard!"

They are considered beneficial for pest control, feeding on small arthropods, including other flies, thrips, aphids, mites, springtails, leafhoppers, whiteflies, beetle larvae, and even termites! They will carry their prey around with them in flight as they secrete digestive enzymes into it and ingest the liquefied contents (similar to spiders). Ohioline.osu

Ready to pronounce Dolichopodidae? Here you go! 

Sunday, December 5, 2021

Jumping Spider

I saw the little quarter inch cutie in the back of my truck with a pile of firewood.  It moved carefully with a few tiny steps, typical of a jumping spider (JS, family Salticidae) which will reserve its leaps for dinner or defense.  Although it was only a quarter inch long, I could make out the little hairs covering the body and legs. When challenged they may face the danger and back away in short spurts.  

When a JS makes its jump it usually leaves a silk thread to dangle from if needed.  When I bumped it with a stick it jumped and hung from the thread as I nudged it into a bug box.  A few hours chilling in the refrigerator let me get a good facial photograph.

JS can be recognized by their eye pattern. All jumping spiders have four pairs of eyes, with the anterior middle pair being particularly large.  They have binocular vision that allows them to measure the distance to their prey, necessary when they pounce on a victim.  The small pair on the top of their head seen above gives them 360 degree vision to movement with a slight turn of the head.

 

You have to love the face of my jumping spider.  Spiders have mouth parts called chelicerae and on JS species they are often metallic blue-green.  These function like fingers, the upper portion fixed and the lower flexible. They can contain glands for the toxic fluid to paralyze prey and manipulate their dinner.

There is a lot more to like about jumping spiders.  For one thing, you can play with them, getting them to chase a laser light as shown in many Youtube videos.  As described in this Atlantic article, their eyes are shaped like little telescopes, a tube with a lens at each end just like Galileo created.  "Only three groups of animals have similar eyes: falcons, chameleons, and jumping spiders."

Bug Lady* describes the advantages of their hirsute body and legs:

"JS’s are relatively short-legged. Each leg ends with many tiny hairs, and each of those tiny hairs is further split into many more hairs, and each of those hairs is equipped with an “end foot.” With all those mini-feet, jumping spiders can boldly go where no spider has gone before—like straight up a pane of glass with the end feet gripping, just like a climbing wall, the “imperfections” in the glass."

There are an estimated 5,000 species of JS and mine doesn't have enough distinctive features to identify it further. The good news is that they can make the identification for mating.  As in many other spider species, sex is dangerous as the female may decide that the first meeting is going to be a "dinner" date.

*Bug Lady's blog has a lot more interesting details of JS at this link.

Sunday, November 21, 2021

Pretty Little Gall

Lynette Elliott CC

This little beauty showed up on our hike through Wilson's Creek National Battlefield, spotted in the leaf litter by a sharp-eyed WOLF student.  It is a small oak apple gall, and a quick trip to INaturalist confirmed its original owner as a speckled gall wasp, Cynips mirabilisAn egg is laid on a leaf in a newly opened bud, along with a dose of a plant stimulating chemical which causes the leaf to grow a protective structure around the egg. There a larva will grow, protected and fed by the leaf.

Parasitoid wasp - Lynette Elliott CC

The female wasp is actually an engineer which provides several other services to nature.  In addition to the tiny wasp that may develop, a parasitoid, such as the wasp above, may drill into the gall to lay its own egg.  That larva will feed on the original owner, eventually killing it.  Once either one of these emerge, other insects (called inquilines) such as ants and spiders may take up residence in the empty gall.

Cynipid parasitoid wasp - CC

Oak galls usually create only mild cosmetic damage to the leaves.  Most online information on them is how to get rid of them including insecticides which can destroy tiny ecosystems that we don't even know exist on our oak tree.  If you see them as a wonderful slice of nature, you can learn more at this site.  For more on the wonderful world of parasitoid wasps, check out this Amateur Anthecologist site.  

(I didn't know either.  Anthecology is the study of pollination.)

Thursday, November 18, 2021

WOLFs to Wilson's Creek

A WOLF field trip always produces lots of discoveries I would miss as my young colleagues are sharper eyed and built lower to the ground.  A student found this beauty in the leaf litter, a 3/4" lichen on an oak twig.  INaturalist confirmed it as a golden-eye lichen, Teloschistes chrysophthalmus Lichens in general are sensitive to air pollution so these are good news.


This North American least shrew, Cryptotis parvus, was spotted dead on the trail.  These measure less than 3 inches from nose to tail tip.  The shrew's eyes are small and its ears are completely concealed, stuffed with its short fur.  Although it resembles a mouse, it's in a completely different order.

Shrews and moles are featured in this month's Missouri Conservationist.  They are predators that specialize in insects and invertebrates such as worms.  Their saliva contains a venom that not only paralyzes its prey but also acts as a preservative.  Since they remain active in winter and need to eat over 50% of their body weight daily, keeping a stored supply of food is important.

Last up is this little stinker, identified by Ruby who had one of Mark Bower's  books in her backpack.  It is a common stinkhorn, Phallus impudicus.  The species name impudicus translates as shameless, immoral, impudent, lewd, etc.  It covers its spores in a foul smelling goop called a gleba.  This attracts flies which think they are landing on ripe carrion, only to be disappointed as they fly off with spores to plant at a distant location.  More on this at this Wikipedia link.

Tuesday, November 9, 2021

Antlered Flutter Fly

This little 4mm fly landed on the arm of my chair on the deck above Bull Creek.  It wandered around slowly, raising and lowering its wings every few seconds as it patiently waited for me to get out my camera.  INaturalist identified it easily as an antlered flutter fly, Toxonevra superbaMinnesoteseasons.com describes it:

 "Toxonevra superba is is a widely distributed but rare flutter fly. It is sometimes called antlered flutter fly, but not by any authoritative sources. It occurs in the United States from Maine to Minnesota south to Georgia and Nebraska, and in southern Canada from Nova Scotia to Alberta. Adults are found on flowers and on low branches of trees and shrubs. Larvae may feed on plant material, or they may prey on the larvae of bark beetles, or both. "

T. superba is a member of the Pallopteridae fly family, so named because of the way the males extend and vibrate their wings.  This earns them common names of trembling-wing, waving-wing or flutter-wing flies.

With its distinctive antler pattern on the wings there are lots of photographs of them on the web but not much more definitive information on the species.

Over 70 species in about 15 genera are found in the temperate regions of the Northern and Southern Hemispheres according to Wikipedia.   With one last look at it below you can see why its 1/6" size is its only protection during deer season.