Sunday, May 30, 2021

Big Head

Big Headed Ground Beetle

On our WOLF School field trip to Bull Mills last week, one of the boys grabbed this beetle, a courageous act considering the size of it's jaws.  This is a big headed ground beetle (BHGB), Scarites subterraneous.  It is just as dangerous as it looks, if you happen to be a caterpillar, maggot, ant, aphid, slug or even a snail.  The student risked only a small painful pinch.

Most of the 40,000 species of ground beetles in the Carabidae family are carnivores in both life stages.  That is not a typo.  Recall that there are 390,000+ beetles in the order Coleoptera, leading Haldane to comment that the Creator must have been “inordinately fond of beetles.” The Carabidae family includes the bombardier beetles which can spray defensive gases and chemicals including formic acid out their posterior glands, giving meaning to the term "bad gas."

BHGB on the move

We frequently get the "What good are .......(fill in the blank)?" question as if all of nature is supposed to meet our human needs.  Ground beetles are good for farmers and vegetable gardeners as they are fast predators and relish the wireworms (click beetle larvae) that attack corn and potatoes.  Some species also eat seeds of lawn and garden pest plants like lambsquarter, pigweed, foxtail, and crabgrass.  The larval forms are also efficient predators and can move quickly as seen in this video.

Dorsal view of BHGB playing dead - Note jaws

Back to BHGB; it is one of the largest ground beetles and its range extends from the US to Central America and the Caribbean.  It is fairly distinctive because it has a wide, flat head and prothorax and a narrow, articulated “waist” between the prothorax and abdomen. The closest match is a stag beetle except for the lack of clubbed antennae.  If touched, they often "play dead" by folding in their legs and arching their backs.

Sunday, May 23, 2021

Dogwood Spittlebug

Four spittlebugs and a visitor sipping latte - REK

Walking the lane, I noticed tiny globs of white froth on the petioles of gray dogwood leaves.  This time of year we see lots of spittle bugs on grasses and soft bodied plants but I had never seen them on woody species.  Googling "dogwood spittlebug" I immediately came up with the cleverly named ........ dogwood spittlebug, Clastoptera proteus.

Wiped clean - REK
We wrote about spittlebugs in a 2015 blog, describing their sucking up dilute plant xylem and converting it to a viscous bubble solution to cover their bodies.  On most grasses and field plants they hang upside down to let gravity do the work of covering them up.  I usually find them singly on a plant, but several of these C. proteus were clustered together along a petiole.

Larva on the left still in foam - REK

Spittlebugs are the nymphs of order Hemiptera (true bugs) in the superfamily Cercopoidea (Spittlebugs).  There are more than 300 genera and 3,000 distinct species.  In addition to the common findings in our fields, there are specialists species that live on pine, alder, and of course dogwood.  All will turn into froghoppers when they grow up.  The adults are more colorful, dare I say cute, but are harder to find.

Froghoppers get their name for the frog-like facial features.  They are world class hoppers with some able to jump 28 inches vertically, higher per body weight than even fleas.  This is 100 times their length - think of you jumping 600 feet from a standing start!  physorg.com  With that tremendous acceleration they would be challenged to avoid slipping on a smooth leaf.  They overcome this by a special adaptation.

"When accelerating for jumps, froghoppers produce traction by piercing plant surfaces with sharp metal-enriched spines on their hind legs, deforming the cuticle plastically and leaving behind microscopic holes, like a biological nanoindenter. This mechanism depends on the substrate’s hardness, and requires special adaptations of the cuticle at the spine tips."  PNAS

The minuscule nymphs need to be wiped before you can photograph them.  Even then you can see them flipping their nozzle around in this video, trying to get their bubble machine started like a tiny Lawrence Welk.

 C. proteus adult, note wings - Claude Pilon
Like grasshoppers, their body shape resembles their parents although they are not exactly "spitting images."  They develop wings and fertility only when they reach adulthood in the 5th instar.   All resemble leafhoppers and most are colorful.  They measure about 1/3 inch long with wings tented over the body in a V shape. Adults feed on a range of host plants, including ornamental perennials.

Most sources point out that spittlebugs do not cause serious damage to plants.  Their pest status depends on where you live.  Along Bull Creek we have hundreds of dogwoods and I have found only 2 trees with a few spittlebugs.  On the other hand if you were in the city and it was a lone dogwood hybrid in your yard, it might warrant treatment.

If you were patient enough to get this far, here is your reward.  Ant Lab has this slow motion video of hoppers hopping.  If you still need more, check out this froghopper gallery from around the world.  Enjoy!

Wednesday, May 19, 2021

Exploring a Little Gem

 

The 5th grade WOLF class attacked La Petite Gemme Prairie last week with their usual vigor.  We found lots of the usual suspects and some great new finds.  My favorite was the beauty above that was on the prairie roses in great numbers.  First, what do you think it is?

The rose occurred in small 1-3 foot clumps scattered across the prairie.  This is Carolina rose, Rosa carolina This prairie rose is found across the US, ranging from glades, open woods, prairies, to wet soils along streams and swamps and low areas.

I was sure that these spiky balls were galls but with my half-vast gall knowledge I field tested it with INaturalist and came up with the spiny rose wasp gall - Diplolepis bicolor.  Cutting one open revealed a lively larva that was constantly jumping and impossible to photograph.  I had to settle for a frame grab from my shaky video seen here.


 

Much of what is written about rose galls focuses on how to get rid of these "pests."  Apparently a rose-growing purist doesn't see the same beauty as my 5th grade colleagues did on the prairie.  There are roughly 50 Diplolepis sp. which are in the Cynipid wasp family.  Their larvae induce galls on wild roses, and rarely on domestic roses.

SRW - Charley Eiseman

The insect overwinters as a larva in the gall.  In early spring the adult wasp matures and chews out through the gall, just as the first cells of leaf tissue appear. After mating it looks for fresh expanding leaf tissue to lay eggs on. The eggs attach to 1-2 plant cells and this induces gall formation begins before the eggs hatch. Once hatched, the larva feeding stimulates gall formation even further.  This provides food and shelter until the next spring.  There is only one generation per year.

Diving deeper, Diplolepis sp. have their own special problems.  While safely hiding in the gall, there are interlopers that can move in with them.  Most Diplolepis galls are known to host inquilines - species that invade and occupy a gall but do not feed on the larva. They may however harm the larva by competing for their resources like a hungry roommate.

As if life wasn't tough enough,  Diplolepis species and their inquilines can be attacked by a wide variety of parasitoid wasp species.  With this complex intra-gall food chain, I no longer feel bad about opening mine up. 

Saturday, May 15, 2021

Frog in an Orchid

In a 3" pot - Ruth Grant
Ruth Grant sent this picture of a tiny (½ inch) tree frog taking shelter in the stem of a native orchid in her yard. She discovered it while removing some protective mulch from around the orchid (not yet in bloom). It is either a gray tree frog, Hyla versicolor, or Cope's gray tree frog, Hyla chrysoscelis. They are often green when they are small.

One of my favorite sounds of night is the call of the gray tree frog. Heard singly it is identifiable, while in a chorus it can even drown out conversation. These calls filling the woods are frequently mistaken for crickets. Here is that memorable call.

Gray tree frogs may have a wide variety of colors from dark brown to green and can actually change color in response to their environment and activities They typically have some irregular dark blotches on the back like our friend in the picture. A large white spot which is present below each eye escaped the camera. The belly is white and the inside of its hind legs is yellow or orange-yellow with gray or black mottling.
The two species of gray tree frog, Hyla versicolor and H. chrysoscelis, are virtually identical in appearance and can only be identified in the field by differences in their call.

Starring me down - REK

Although they share the same terrain and habitat they have maintained separate species. Here's an amazing fact! In spite of their great similarity, H. versicolor has has only half as many chromosomes as H. chrysoscelis.

They feed on insects, spiders and other invertebrates, caught with a quick flick of their stick tongue.  They are in turn preyed upon by bullfrogs, wading birds, and snakes.  They produce a toxic skin secretion that can cause extreme discomfort to the eyes, lips, mucus lining of the nose, or open cuts and abrasions. Careful hand washing is advised for anyone after handling gray tree frogs and never kiss one as there is no record of one ever turning into a prince.

We recently lost a friend of nature, Dr. Bob Lovett. He created the Lovett Pinetum and was an active member of many conservation organizations. He had a long and complicated illness the last few years that made this story he sent me in 2019 all the more touching.
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Franklin “the Frog” - by Bob Lovett

 

He came three days after we first turned on our front yard waterfall. His croak was so loud that we could hear him from any room of the house, beginning each night at about 9:15. It took us two nights to locate him visually because he was so much smaller than his croak and he blended in with a variety of backgrounds.
The first photo was at midday on his favorite perch on the stone and mortar surface on the front of the house about 7 inches above ground and 5 inches from the nearest shallow water at the top of the waterfall.

The second picture is at the same location at night where he turns, without changing location, from coarse textured mottled gray to smooth dark green- black. As he became more familiar with us, he would croak with the flashlight trained on him..... his throat and sides would double in dimension just before he let out each roar.




The third photo is at night semi-emerged in the shallow water and croaking in his brown uniform matching the rock on which he is perched.

Then about 2-1/2 months after he came to us, he vanished.   Since we saw and talked to him every day and evening, we miss him greatly.  Prior to Franklin I never could have imagined falling in love with a frog.

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The next time you are outside among the trees on a sultry night, just picture a one to two inch wonder with the big voice. It might be Franklin, talking to Bob about nature.

Monday, May 10, 2021

Battling Skinks


These two five-lined skinks fought continuously on our deck for five minutes before one escaped over the edge.  You can see a little of the battle in this Youtube video.  Their orange heads identified them as males which were competing for territory.  Why the orange head?  In breeding season, the males develop their bright orange color, presumably as a way of attracting females.  They fight other males aggressively to defend their territory and the females within it.

This could easily be confused with mating behavior.  In courtship the male grasps the necks of a receptive female in his jaws after approaching them from the side. "Using the tail to align cloacal openings, males initiate copulation by inserting one of the two hemipenes into the female's cloaca. Copulation events typically last four to eight minutes." Wikipedia

In addition to sight, skinks rely on their vomeronasal or Johnson's organ to "taste" male chemicals.  This organ is located at the base of the nasal cavity in all lizards and snakes.  It is divided by the nasal septum, allowing the animal to know the "odor" comes from the right or left.  This is what a snake is doing when it is flicking its tongue in and out as in this video.  The tongue doesn't taste, it is transferring the odor to the Johnson's organ.


Freshly hatched five-lined skink

"Now where did I leave my tail?"

Young skinks have very prominent white stripes and a bright blue tail.  Like many other lizards, five-lined skinks will break off its tail when it is grabbed.  The tail will continue to thrash about vigorously, distracting the predator and allowing the lizard to escape.  You can see this in action in this Youtube video.  The skink will frequently regrow a smaller tail.

In the south, blue-tailed skinks are frequently referred to as "scorpions" and are believed to have a venomous sting. While this belief is completely false, maybe it will keep kids' hands off their tails. 


Female skinks are very attentive mothers, guarding and nursing their eggs. They will frequently coil their body above or around the eggs to warm them.  They will roll displaced eggs with their head and consume rotting eggs.  They even urinate in the nest and turn the eggs to maintain humidity.  No one has studied what the young skinks think of the last fact.


Update 5-18-2021

This pair was mating at the same location as the fight aboveThey were very patient and gave me permission to post this video.  Youtube asks if it is "made for kids" and I answered yes as the were "making kids".  You can see it at this link.

Friday, May 7, 2021

Skullcap Skeletonizer

 
  
SSM - INaturalist CC

Tonya Smith sent me this picture of a beautiful little moth which she identified on INaturalist as the skullcap skeletonizer moth (SSM), Prochoreutis inflatella.  Downy skullcap was growing at the Springfield Lake Boathouse right where she discovered the little SSM. The moth's wings have beautiful silver streaks with a wingspan less than half an inch. Adults are said to be on wing from June to September. but this was photographed in May.  There are several generations per year.


Downy Skullcap-Wikimedia

Downy skullcap, Scutellaria lateriflora, is a pretty wildflower in the mint family.  It is showy, a nice addition to a garden.  It also is packed with a lot of chemical punch. It produces many chemicals which have been promoted as herbal medicines for sleep or a mild sedative.  Cherokee women may have used it to induce abortion.  Because the foliage is bitter-tasting and possibly toxic, mammalian herbivores usually don't bother eating it.


Leaf skeletonized by SSM - Moths of North Carolina

The SSM larvae feed on Scutellaria species, including downy skullcap. They skeletonize the leaves, bending the leaf upwards and the edges together. They feed under slight webbing. The first larvae appear in March, only shortly after the host plant begins growth.  Pupation occurs in a fusiform, multi-layered cocoon of white silk. 

Skullcap Caloptilia leaf mines*
Another moth with a taste for skullcaps is Caloptilia scutellariella, the skullcap caloptilia moth. These larvae are leafminers, spending their childhood inside the lower side of the leaf epidermis.  They then crawl out to pupate in the rolled up leaf base.

*Leafminers are cool.  Spending their infancy crawling between the upper and lower surfaces of a leaf, they leave a trail of frass.  Charley Eiseman's Leafminers of North America is encyclopedic and takes no shelf space as a continually updated huge PDF, highly recommented.