Saturday, December 7, 2019

Grapefern



Hiking along the Mail Trace Road, Barb spotted a solitary green fern poking out of the drab floor of dried leaves.  It had what appeared to be green leaves spread out around the base and a 12" bright green stalk with light green bumps lining the underside of stems like little grapes.

When she touched the stalk there was a tiny cloud that drifted away.  The cloud of spores was released with each touch, as shown in this video.  We went back home to identify it.  What in the past would have been a nearly impossible task of thumbing through books became a one minute exercise with the photo above sent in to Inaturalist.

Wikipedia
This is a cutleaf grapefern, Sceptridium dissectum, a common fern, although easy to overlook when hiking as it is frequently found in overgrown disturbed areas.  It is a perennial but is easier to find this time of year because of its strange growing season. To grow it depends on a mycorrhizal fungus association in the soil.  Ferns are different from our common flowering plants and don't get as much respect, the Rodney Dangerfields of the plant world.  Stick with me as we muddle through this difference.

This grapefern produces a single frond (large, divided leaf) which spreads out at ground level, usually with lacy edges.  This often turns from green to a bronze color during the winter.  In fall, mature plants grow a single fertile section, which stands on a long stalk above the sterile part.  They are named for the round, clustered sporangium (spore cases) extending from the top of the stalk which have some resemblance to a bunch of grapes.  When we touched the stalk, the cloud you saw was the spores drifting away to the ground.

From here the fern life cycle gets very technical and hard to describe in simple terms.  Rather than confuse you further, I would suggest reading the best description I have found, here from UPenn.edu.

Resurrection fern during dry period
 Add water, no stirring required.
Another common fern species that can be overlooked is this resurrection fern, Pleopeltis polypodioides.   Gala Solari shared these photographs before and after a rain.  This is an epiphyte or air plant, meaning that it gets its nutrition and water from the air and the bark surface of a tree.  It is able to survive long dry periods and lose up to 97% of its water.  It does this by curling up its fronds, turning gray-brown and appearing dead.  Add rain and viola! it greens up.  It can survive drought for many years this way.  You can watch one revive in this time-lapse video.


From now on I will give a lot more respect to the ferns I encounter, even if I am still struggling to understand their strange life cycle.

You can read about the Christmas Fern in this month's Missouri Conservationist 
at this link.

Sunday, December 1, 2019

Insect-loving Fungi


During a recent WOLF School field trip at Bull Creek, one of the fifth graders turned over a rotting log and discovered the grisly crime scene above.  By carefully excavating it, he exposed the remains of a lepidoptera pupa case, its contents consumed by a parasitoid fungus.

These white powdery structures are the fruiting bodies of an entomopathogenic fungus, Cordyceps tenuipes. (Greek entomon=insect).  If one of its spores comes in contact with an unlucky moth or butterfly pupa or larva, it will germinate, penetrate the cuticle and then grow inside the host. This eventually leads to the death of the insect. Then the spore-bearing fruiting bodies emerge from the cadaver.  Remnants of the victim can be seen in this photo.

There are a great number and variety of entomopathogenic fungi. In fact, 5 of the 8 fungal phyla contain species which have evolved to feed on insects.  C. tenuipes and some other species have been studied for possible medical applications which are popular in China.

Cordyceps militaris in the soil - Mark Bower
Cordyceps militaris on a dead caterpillar - MB
A common Cordyceps species is C. militaris which Mark Bower shared with me.  Michael Kuo of Mushroomexpert.com describes it as "pretty much the coolest mushroom ever," but to identify it you need to dig a little deeper.  It parasitizes puffball mushrooms as well as insects, so simply plucking it from the ground leaves the underground origin a mystery.  In general it is always a good idea to dig down when collecting any mushroom because the substrate may help you identify it if only to know that it grows on wood.
 
Some species simply enter their host and devour it from the inside.  Incredibly, a few species can infect the creature’s brain and muscles and compel it to perform certain tasks.  For example, Ophiocordyceps unilateralis and C. lloydii fungi may direct an infected ant to climb a tree to a specific height so that the fungal spores will rain down on the unsuspecting ants below.  In an example of familiarity breeding contempt, Kuo states:
"Some ants and termites that have evolved the ability to detect Cordyceps-infected compadres; sentry soldiers guarding the Queen kill the infected insects and take their bodies far from the nest before they can threaten the colony."
Spider succumbed to Torrubiella arachnophila -MB
Now for a specialist in action we have Torrubiella arachnophila.  The species name arachnophila comes from arachno, "spider," and phílos, dear, beloved."  I suspect this is a case of unrequited "love," more likely an abusive relationship, as the fungus gets all the affection.   According to Mushroom Observer its "deprecated synonym" is Gibellula leiopus (Vuill. ex Maubl.) Mains, a debate we will leave to the taxonomists.
Beauveria bassiana on a wasp - MB
A final fungus that Mark photographed is "Beauveria bassiana," a species found around the world growing in the soil and parasitizing insects.  It is being used as a biological insecticide.  Studies showed it was highly effective in controlling bed bugs.  If you get the itch to try it you can find it at your nearest Amazon link.

Saturday, November 9, 2019

Dermestids in a Skull

Dermestid beetle larvae
So, reaching for a new height in the ridiculous pursuit of weird tiny insect life, I present you with dermestid beetle larvae found in a deer skull.  We have taken this skull to WOLF the last 3 years while it spent the rest of the time in a bag upstairs at the creek house.  When Barb took it out at WOLF some powder fell out of the base of the skull and a student noticed that something tiny was moving.  Magnification with a digital microscope showed cute fuzzy larvae.

Chris Barnhart identified the photograph as Dermestid beetle larvae.  There are over 500 species of beetles in the Dermestidae family with a variety of lifestyles.  Most of the larvae are scavengers, living on dry plant and animal matter, sometimes with very specific tastes.  Dermestid larvae are profoundly covered with varying lengths of hairs (setae) that gave them a distinctive appearance. The larvae are generally dark brown to black and go through complete metamorphosis.  Adults are less commonly found and feed on flowers and shrubs.

Ventral view of exuvia within their dried frass
Some dermestids are famous for their forensic connections, living on dead animals and giving clues of the time of death.  They are available on line to use in cleaning skulls and bones of animals in laboratories for the study of anatomy.  Our larvae had been surviving in a deer skull for several years.  Fortunately they like to eat dry dead stuff.

Home on the frass
Above you can see the results of life in a deer skull, lots of larvae moving around in their world of frass and molted skins (exuvia).  This prompted me to make  this video for a closer look.  For more information on the value and risks of using Dermestids to clean bones, watch this educational PBS video showing the beetles at work.
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More species are discussed at Bugwood.org/

Wednesday, November 6, 2019

Yellowjacket Nest

Syrphid fly, Milesia virginiensis on my arm

I was chasing a tiny skink through the leaf litter six feet from our front door when I saw several yellow flying insects.  We have Syrphid or flower flies on our deck regularly, scaring visitors as they look like yellowjacket wasps but I wasn't fooled..... yet.  I got out my pocket camera to get some closeup videos, a big mistake.  Just then I saw five swarming around in the grass and then more hovering around a finger sized hole.  I thought "Do Syrphid flies nest communally?"  just 2 seconds before the first of several stings - "Yellowjackets!"


I ran backward swatting them off and the attack stopped as the swelling started under three stings.  We love nature but occasionally nature gets too close and our house qualifies as unnatural.  After applying ice to the stings with unimpressive results, I got a can of "kills on contact" wasp spray and soaked the hole from a distance several times.  I returned 20 minutes later with my telephoto camera. (Note to self - video wasp nest = telephoto).
 

In spite of the insecticide, the hole was busy with wasps coming and going for the next 8 hours.  Many of the outward bound were carrying something in their mouths.  They were moving too fast to see what they were carrying.  It looked like they were panicked and evacuating the hole.  So much for the "kills on contact" on the spray can.  Apparently Ozark yellowjackets can't read.


YJ with a mouth full of rock - REK
After converting the video to 8x slower playback* it became obvious that they were not planning on leaving.  They were actually carrying out small pebbles, enlarging their quarters, carrying on like nothing had happened.  I had a lot to learn about yellowjackets.  This intriguing Youtube video by Bret Davis, aka Hornet King** was a great introduction to the subterranean world of yellowjackets.

Outer bottom layer with side holes - B. Davis
YJ usually build their paper nests underground, starting in a small hole created by a mouse or something similar.  As they create the cells for the offspring of their queen, they work around the outside edges of the paper nest, excavating rocks and soil to enlarge the nest.  As the colony grows they create several side holes (starting at 20:30), slowly digging a larger hole which will be filled with new layers of the nest.

Seven layer yellowjacket nest -  Hornet King, B. Davis
So how big do they get?  This one was removed from a 14" X 9" hole fully excavated by the wasps themselves!  I don't know about records but Bret's weighed an estimated 10 pounds.  (Taking a nest with scattered yellowjackets on it to the bathroom scale in the name of science probably isn't a good idea.)  His nest was seven layers deep.

Weaving a cap -Click to enlarge  (HK)
His video is 27 minutes long but well worth the time.  Unlike many videos focusing on the excitement and danger of stings, Hornet King vividly shows the process of nest building.  Here for instance he shows the larvae beginning to weave a silk cap to to paper homes where they will pupate.

As I nursed the swelling over the next 5 days, I identified my new neighbors as eastern yellowjackets, Vespula maculifrons.  Baldfaced hornets (Dolichovespula Maculata) are yellowjackets with a pale makeup.  Both are colonial nesters but hornets nest above ground while YJ are usually below ground or in enclosed spaces like the soffit of a house.  We have that problem with our red Polistes wasps, but at least they aren't quite as irritable.

Additional thoughts from Hornet King:
There are many subspecies of wasps in the Dolichovespula grouping. Another of the Aerial nest builders is the Dolichovespula Arenaria, which look very similar to the subterranean YJ (Southern Yellow Jacket - Vespula Squamosa) species. This subject is always a area of confusion for my many of my viewers as they think "Yellow Jacket" is a term only given to yellow and black wasps. However, there is more to the classification than just its yellow body (Bald faced hornet being a prime example)

 Promachus hinei with YJ

I did have some slight consolation as I sat on the porch swing balancing ice on my stings.  A loud and coarse buzz announced the arrival of a robber fly, Promachus hinei, on the swing chain.  It was holding a yellowjacket in its jaws and seemed to be showing off its catch.  I photographed it and watched it fly away.  It pierces the body of its victim and sucks out the insides, appropriate justice in this case.

Slow motion video of yellowjackets rock excavation
**  The Hornet King Youtube channel has many more detailed explanations of the nests of other colonial nest builder wasp species.
Yellowjackets on Bugguide.
Yellowjackets and Hornets on University of Florida.edu

Monday, November 4, 2019

Frost Flowers Revisited

Early frost Flowers - Mark Bower
We are at the beginning of frost flower season although few botanists will ever see them.  The "blooms" extrude around the lower stems of Verbesina virginica on nights where the temperature drops well below freezing and they fade after a few minutes of direct sun or as the temperature reaches the mid thirties. 

The delicate sheets of ice split the stem's epidermis lengthwise, thin enough that you can see your finger print through them.  Early in the season they may extend 12 to 24 inches up from the base but as the winter rolls on they become shorter and eventually somewhat thicker.  A hard freeze for several days which freezes the roots will end the season prematurely.  Our personal record was 40 nightime blooms over a winter.

The mechanism of FF is the ability of water to "supercool," that is to drop below 32 degrees without crystallizing.  This is what allows clouds to hold liquid water in the colder atmosphere.  When supercooled water is shaken or encounters a foreign particle it freezes rapidly, accounting for the icing on aircraft wings when they fly through cumulus clouds.  This also accounts for the large accumulation of ice on trees and powerlines in ice storms that are so memorable to those of us in the Ozarks.

This is what happens when the supercooled water extrudes from a V. virginica  and contacts the outer stem's epidermis.  You can see the dramatic ice crystalization of supercooled water in this demonstration on Youtube.


Mark Bower
FF asks a question - Mark Bower
As frost flower season progresses the "blossoms" are lower to the ground and take on many extraordinary shapes.  Stems may be damaged or horizontal but the ice marches on.  Cups, curls and spirals are created, demonstrating nature's varied designs and sometimes a sense of humor.


















White crownbeard - MDC
This is the time of year to be watching for frost flowers along the weedy edges of fields and roadsides.  These most commonly occur along the stems of Verbesina virginica, a plant with small white flowers on 3-5 foot stems that are winged along the edges.  It has a confusing list of common names including frostweed, white crownbeard, iceplant, iceweed, and wing stem.
Frost flowers on dittany
FF also can be found around the base of Cunila origanoides, whose common names include dittany, wild oregano, stone mint, and frost mint, and Pluchea camphorate. also known as stinkweed.  These are smaller plants that are common in Missouri but less likely to cover a field edges.*


You can see some of the exquisite shapes that Mark Bower photographed before this last Friday's WOLF School field trip in this Flickr album.
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* Reports of FF on yellow crownbeard (Verbesina alternafolia) are probably due to confusion with Verbesina virginica as they frequently grow together and are hard to separate in winter time when the flowers are off.  We have been monitoring tagged yellow crownbeard for years and have never seen FF on them.

Thursday, October 31, 2019

Leopard Slug


This story is from Alee Huerta who has returned to the MN fold after an absence while pursuing her education.

This past weekend we had a Leopard Slug crawl across our porch. My 1st thought was to grab the salt... and I did.  But as my 7 year old buddy and I plopped down with the salt, my inner Naturalist was like.... "hold up."  I'm glad I took the time for education because I found out that these slugs don't actually destroy living plants, a common misconception.  Leopard Slugs (Limax maximus) eat fungi, rotting plants and even other slugs. They need to keep their bodies damp in order to breathe, so are usually found in dark, damp places, particularly among rotting logs.

Mating Slugs - Wikipedia
All slugs are hermaphrodites, meaning that each slug has both male and female sexual organs. They still need to mate with another individual though and LS have quite a spectacular way of doing this. The two slugs climb a tree or other structure, then hang from a branch on a thick strand of mucus, intertwined with one another.   Their sex organs protrude from their heads and intertwine to exchange sperm.  These are bluish colored shown in the photograph.  Editor's note:  This is a family blog but we will recommend this graphic BBC video as it is narrated by the very proper Richard Attenborough.



After mating, each slug lays clutches of transparent, round eggs in damp places.  As slug babies, they are a primary food source for lightning bugs! I love lightning bugs, so the way I see it, to love any one certain thing you need to respect everything that one certain thing needs.  They reach sexual maturity in 2 years and can live for 3 years.


Limax maximus, literally biggest slug, originally were native to Europe and Mediterranean countries of Africa and were first found in Philadelphia in 1867.  In spite of their top speed of 6" per minute they really get around and are now found around the globe! They are almost always found near human habitation — usually in lawns, gardens, cellars, outbuildings or in other damp areas.

LS is generally a nocturnal slug that feeds mostly on rotting plant matter and fungi as well as other slugs. In Texas and Oregon it can sometimes be a pest of gardens, greenhouses, cellars, and mushroom beds.  On the other hand, by eating dead and rotting plants, as well as fungi, Leopard Slugs recycle nutrients and fertilize the soil.
 
Our LS like many other slug species have a small disc of shell inside their body. Slugs evolved from snails and this disc is a remnant of what used to be the snail’s shell.  They can come in a wide range of shades although these leopards never change their spots.

Finally, research by Christie Sahley and colleagues have demonstrated associative learning in LS by aversion therapy.  Carrot and potato juice normally attracts them.  After they have been exposed to them flavored with an additional bitter dose of quinine sulfate, these attractants subsequently lose their gustatory charm.  Yes, it appears you can teach old slugs new tricks.
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Dr. Chris Barnhart and MDC have just published Land Snails and Slugs of Missouri, available in many different formats at this Archive link.  You can download it as a PDF or Kindle document.

Sunday, October 13, 2019

Twig Girdlers

Twig girdler, Oncideres cingulata - Dave Rintoul
This is the time of year our forest floor becomes littered with small tree branches with a distinctive break at the end.  They look like they have gone through a blunt pencil sharpener, ending in a jagged tip.  This is the work of twig girdler beetles, Oncideres cingulata.  These are long-horned beetles of the Cerambycidae family.  



In the summer after mating, the female straddles a small branch and chews a V-shaped groove in the outer portion around the twig, leaving the center portion intact.  Her feet grip the tender bark, leaving a series of horizontal grooves in the distal branch.

Hole for egg - Chris Barnhart (CB)
Next she chews a small hole in the bark of the outer half of the branch and deposits an egg under the bark.  
The eggs are long and narrow, fitting into a tiny hole usually at the site of a side branch.
Egg in its chamber - CB  Click to enlarge

The number of eggs per twig normally ranges from 3 to 8 but may range up to 40. Adults live 6 to 10 weeks. 

Each female deposits 50 to 200 eggs which hatch in about 3 weeks.   OKstate.edu

Larva writhing around in its frass chamber - (CB)
This will be her offspring's home until next summer, slowly enlarging its chamber while living in its woody poop (frass for insect connoisseurs).  Her larvae require dead wood to develop and the cut effectively cuts off the twig's circulation.  They cannot fully develop in green twigs with high moisture content. 

The legless grub will live in the twig all winter whether it falls to the ground or occasionally dangles from the tree. The chamber hollows to provide a winter home as the grub rests.  It starts feeding again in the spring and grows up to an inch long, living in a world of its frass which provides some insulation.  Eventually it chews an exit hole for the future, then pupates in the frass before emerging as an adult beetle in late summer.

You can see some of the action in Dr. Chris Barnhart's video here.  Meanwhile a couple of beautiful final portraits from Chris of the emerged adult, Oncideres cingulata.  
Note: 2013 blog updated with video.