Monday, May 18, 2015

Rhubarb Weevil

Rhubarb weevils (Lixus concavus) also known as Rhubarb Curculios are commonly found throughout the Eastern United States and portions of the Western United States such as Utah, Idaho and Texas. There are known populations in Ontario, Canada as well. 

They use plants in the genus Rheum as their host plant, much to the detriment of their offspring (more on this below). This includes Rhubarb, from whence this beetle gets it's common name. But they also use other plants including dock, thistle and sunflower. I find them frequently in May on curly dock that grows near our garden. In March and April when the curly dock is young and tender it attracts a completely different beetle called a Green Dock Beetle. When those beetles leave, the weevils show up and feed on the dock in its much larger state. 

Adult beetles overwinter in leaf litter and become active in May. They will begin laying eggs in host plants, typically one egg per plant. Even though these beetles share a common name with the rhubarb plant, they cannot complete their life cycle within the stalks of rhubarb. Eggs laid within the stalks of rhubarb are quickly consumed by a sticky sap-like substance that the plant produces in response to a foreign object or injury. This destroys the egg(s). Instead the weevil will use sunflower, thistle and dock most often as a suitable host. About 10 days after the eggs are laid the larvae will hatch and begin feeding. They work their way down the stalk to the ground where they will pupate. This process takes approximately 9 weeks. Right before pupating the larvae will chew an exit hole into the plant that the adult can emerge from after completing pupation. The adults will feed for a few weeks on the leaves of the plants before the colder temperatures drive them into sheltered areas where they will spend the winter. 

This species of weevil is one of the largest in North America, reaching up to 1/2 inch in length. They are black beetles covered in a fine golden dust. Like many beetles when they are alarmed they will roll over and play dead often rolling off the leaf or plant that they are feeding on. This must work well for the beetle, as I've had them do this and they virtually disappear once they hit the ground never to be seen again. 

If you have these beetles feeding on your sunflowers or rhubarb, usually handpicking the beetles and destroying them is sufficient to get rid of them as they rarely show up in large numbers. It is also recommended to kill plants like dock or thistle, which may be nearby your garden plants, that are also used as host plants. This can go a long way in reducing their numbers. Make sure to kill the plants in June when the larvae will be inside the plant feeding. Since we do not grow sunflowers or rhubarb I don't worry about them at all. The curly dock they feed on here is a pest plant and they are welcome to it. Plus I find them attractive and interesting beetles.


Wednesday, May 6, 2015

Northern Paper Wasp

Young female paper wasps (Polistes fuscatus) are actively building their nests right now. They will seek almost any sheltered place to start their hive, including under large limestone rocks like the one pictured here. You will also find them in the eaves of homes and garages, inside old sheds and outbuildings, inside chicken coops, barns, etc. This single pregnant queen will form the nest and lay her eggs. When the eggs hatch they will be all infertile females, that will take over expanding the nest and feeding the offspring of the original queen. As the hive expands and becomes full of female minions they will often become very defensive and stings routinely occur if you venture too close to the nest. Give them space and you shouldn't have any problems at all. Wasps are able to sting over and over again which means an encounter with an angry hive can be a very bad experience. I've personally not had much trouble with them, but I know many people who have. Stings are painful and often cause swelling, itching and in rare cases anaphylactic reactions in those who happen to be allergic to bee or wasp venom. 

Reaching lengths up to 21 mm (or nearly 1 inch) makes them a fairly large wasp. There are four recognized color forms of this species depending upon the region where they are found. In our area, females are darker in color than males and have a reddish colored face. Males appear in late summer and early fall and will have a greenish-yellow color with greenish colored eyes. Males cannot sting as they lack a stinger. They do not protect the hive, or feed the queens offspring therefore they do not need stingers. Their only purpose is reproduction. Once mated the males will die and so will any females that have not reproduced. Newly bred queens will overwinter in leaf litter, under rocks, under the bark of trees or any sheltered area out of winters cold temperatures.

(A harmless male hanging out on my hand last fall)

Adults feed on nectar and sugary foods such as apples, grapes and other fruits. They will also show up at Oriole and hummingbird feeders. The females responsible for rearing the young will seek caterpillars and other soft bodied insects that they will chew up and feed to the developing larvae. This preference for caterpillars and other pests helps control nuisance insects like a wide variety of moth caterpillars that may feed on corn, soybean, cotton and other agricultural crops. Biological control at it's best. 

Females chew wood to utilize in making their nests. They will tear off tiny pieces of wood and chew it in their mandibles with a mixture of water they've collected that makes it malleable and easy to form into the distinctive hexagon-shaped papery nests we are all familiar with. Some of these nests may contain dozens, if not hundreds of protective females and additional dozens of larvae. Members of the same nest recognize intruders by how they approach the hive and will chase off any wasp that does not belong to their colony. If a wasp approaches the hive in a rapid, purposeful manner it is assumed she belongs there. If a wasp hovers in a slow manner near the hive, it is assumed she does not belong and is treated accordingly. If the intruder manages to get past any females guarding the nest, her visit won't last long. Usually within a few minutes her presence will have been found out and she will be aggressively invited to leave.

Towards the end of summer the queen will release a strong sexual pheromone, made of venom, on the hive once it has been deserted. This intoxicating "perfume" will send the males into a mating frenzy. Males will perch on a higher platform basking in the sun, waiting for reproductive females that they can force their attentions upon. Females will struggle against the males and sometimes escape their grasp, only to find themselves pursued again and forced to submit to the males attention. 

Once mated, bred females look for sheltered areas to spend the winter. In spring she will join aggregates with other bred queens for a period of time before they disperse and begin hive building. The initial offspring of the queen are all infertile females, later males will be produced followed by reproductive females and the cycle will start all over again. 

While stinging insects are rarely anyone's favorite insect; and if these wasps decide to build their nest right outside your back door or some other location where you will be in constant contact with them, destroying the nest may be the only option to avoid painful stings. However, if the hive is safely away from human contact, they are best left alone. They are excellent pollinators, great biological control and should be considered beneficial to humans.

Thursday, April 30, 2015

Emerald Euphoria Beetle

Emerald Euphoria (Euphoria fulgida) are beetles in the family Scarabaeidae that are native to North America. They are not especially common east of the Rocky Mountains and can be highly variable in their coloration.
 There are 59 described species within the genus Euphoria and all are native to the Americas. Most are found in Central and South

The one pictured here was found yesterday under a rock and was already dead. I'd never seen a beetle quite like it and I'm not sure what killed it. It did not appear to be harmed in anyway and was completely intact. When I first found it I thought it was a Green June Bug (Cotinis nitida) which are very common around here. The coloring wasn't quite right for a Green June Bug so I suspected it was something different and decided to keep it until I could get an ID on it. Once I figured out it was a new species for me I decided to keep it to add to my collection. It's always fun to find something new, a lifer if you will.

The range for this particular species is listed as New Mexico east to Florida, and Maine west to Colorado. There is a blue form that is found from New Mexico to Colorado. They are a medium sized beetle reaching lengths from 12 to 19 mm. Overall greenish in color with bright shiny elytra and pronotum. There may be some amber, reddish-brown or gold coloration along the edges of the wings.

Adults are often found in meadows, or fields full of flowers where they consume nectar or pollen. They may also be found in timbered areas where they will also feed on sap leaking from trees. In flight they are often mistaken for bees. They are most often encountered from May through July, but may be found as early as March or as late as November.

The larva are found a few centimeters under the surface of rich soil, and organic matter like manure, and compost. May also be found in pack rat middens, and ant nests. Larvae feed on manure. Depending upon the species, some will overwinter as adults and others spend the winter underground as larva.

If you'd like to read more on this beetle please visit my friend Eric's blog post at Bug Eric

Goes to show that you never know what you will find when you flip rocks, almost always it is sure to be interesting.

Sunday, April 19, 2015

Northern False Widow

Northern False Widows (Steatoda borealis) are very common in Missouri, and they happen to be one of the spiders I receive a lot of inquiries about. They are native to the Eastern United States (mostly in the Northern states) but are now found in many Southern states. As its name suggests it resembles a widow with a very round, bulbous abdomen and dark colored body. When faced with a spider that looks like a black widow, people want to know if these spiders are dangerous. I am happy to let them know that this spider is completely harmless and poses no serious threat to humans whatsoever. I point out that true black widows are "black" and have red markings on the underside of their belly, usually in the shape of a hour glass. Although there is a species of Northern Black Widow in Missouri that has a broken hour glass, or something that looks like two triangles with points that don't quite touch. While black widows can give a painful bite that can land you in the emergency room, bites are rare as these spiders generally remain in or near their web and aren't prone to traveling much to seek prey, which means encounters with humans generally don't happen.

 There are a few spiders in the genus Steatoda which possess venom capable of causing medically significant responses in humans, but most do not. The majority of people who may be bitten by one of these spiders would not experience any reaction at all. Like all spiders they have venom which is used to subdue prey, it is not designed to cause harm to human tissue, but if you are allergic to the proteins in the venom a very serious reaction may occur.

This species has a dark brown body, and a lighter brownish-red abdomen with a yellow or cream color "T" marking. The underside of the abdomen is much lighter than the top.

 Reaching lengths up to 7 mm, females are larger than males, as is the case with most spiders. Females construct messy webs that males will tap on to signal to the female that he is nearby and interested in mating. The male will tap on the web in a specific little dance that hopefully the female will find enticing in terms of mating and not dining. If she is not in the mood for mating, she will capture him and treat him like any other unfortunate arthropod that finds itself in her web. However if she is receptive mating will occur. After mating, the female will form two or more egg sacs that she  places at the edge of her web and will guard. Egg sacs hatch in the fall when many dozens of spiderlings will disperse into the environment. Some females will overwinter if the weather is warm enough or if they are able to find a sheltered area.

These spider will often build their webs in the corners of our homes, especially in cellars and basements, as well as outside under logs, rocks or other debris. Like all spiders they are beneficial because of their preference for many insects that may become pests like flies and certain species of moths.

Monday, March 23, 2015

Banded Ash Borer

This seems to be the week for longhorn borers as our woodpile came to life on Saturday with dozens of these long-legged, longhorn beauties. I had never seen this particular species before and after inquiring on facebook, one of my friends knew right away that is was a Banded Ash Borer (Neoclytus caprea). Like the Painted Hickory Borer I posted last week, this one is also a wasp mimic which is easy to see why by the image to the right. Their black and yellow (or white) striped markings and long legs are very wasp-like in appearance.Their movements are also erratic like wasps. It was very difficult to get clear images of these beetles as they are very fast moving and prone to flight when you get anywhere near them. I spent well over an hour just trying to get a few passable images. Insect photography will certainly teach you patience....or drive you buggy, not sure which. 

Banded Ash Borers are found throughout Eastern Canada and most of the United States. They use Ash, Mesquite, Hickory, and Elm to lay their eggs in. Rarely do they infest healthy trees, instead they prefer trees that are stressed or dying. Adults emerge early in the spring, typically in April, but obviously as early as March if the weather is warm enough. They will also be found in firewood and emerge from logs in your homes, sometimes in large numbers which can be worrisome if you aren't familiar with them. They are harmless and will not bite, sting or otherwise harm us. They will also not harm your woodwork or furniture. They look for trees or firewood with the bark still intact in order to lay their eggs. If you are overly concerned about finding these beetles in your home, removing the bark from your firewood will solve the issue. 

Females lay their eggs in the cracks or crevices in the bark of host trees or firewood. The eggs hatch and the larvae, called round-headed borers, burrow into the sapwood where they feed until late summer at which time they form pupal chambers in the wood just below the bark and spend the winter in this stage. In the spring the adults emerge and look for mates. They complete one generation per year, but if the female chooses firewood to lay their eggs it may take as long as 2 years to complete their lifecycle.

There are few insects active this time of year, so when warm days bring out pretty beetles like this, it is hard to not get somewhat excited.

Tuesday, March 10, 2015

Painted Hickory Borer

The Painted Hickory Borer (Megacyllene caryae) in the family Cerambycidae, is one of the most frequently misidentified beetles in their range (more about this later). Each spring, usually in March or April this beetle emerges from hickory trees and other closely related trees. In some cases if you burn wood in your fireplace or wood stove you may find one of these colorful beetles flying or crawling through your house as early as January or February. Hickories and Pecans in the genus Carya are the main host tree for this species, but they will also be found emerging from hackberry trees in the genus Celtis. My husband cuts and burns hackberry in our wood stove as well as other species of wood like black locust, hedge and oak. I've found close to a dozen of these longhorn beetles in my house in the past few weeks. They have most certainly come from the hackberry logs since we don't burn pecan or hickory. The one pictured here I took outside and placed on the closest available tree, which happened to be a cherry. I'm sure it will make it's way into our timber where it will find a mate and lay eggs on the hickory trees that are there. We discovered two recently deceased shagbark hickories that will make a great host for them.

                                (For comparison Left: Locust Borer; Right: Painted Hickory Borer)

As I mentioned above these particular beetles are one of the most misidentified beetles in their range. So what beetle are they confused with? Another longhorn beetle called the Locust Borer (Megacyllene robinae) which looks nearly identical to the PHB. So how do we tell the difference? Well it can be difficult, even for experts sometimes, but the easiest way is based on seasons. The Painted Hickory Borer is found in the spring, whereas the Locust Borer is found in the fall. Locust borers are frequently found feeding on goldenrod which blooms in autumn. Their host trees are locust trees as their common name would suggest, especially Black Locust. PHB use trees that are already dead as their host, whereas Locust Borers often use viable, live trees. They are considered a major pest of the Black Locust, but some would say that is a good thing. I know several individuals who consider the black locust tree a pest itself. So I guess the pest classification of the black locust borer is all relative to how you feel about the black locust tree. I don't have an opinion one way or the other about black locust trees. I know their blooms smell fantastic in the spring and when I am hiking in the timber it is a welcome treat in the spring to catch a whiff of their blossoms on the breeze. Not only do they smell wonderful, they are edible too!  Black locust wood burns well as firewood and common enough to be easy to come by. But to many they are thought of as invasive.
Other identification characteristics:  PHB have reddish colored legs which Locust borers do not have. PHB also have yellow and white, broken lines on their wings. Locust borers have wider yellow lines on their wings without breaks in them.Use the above photos to compare the two species and notice the locust borer is on goldenrod....their favorite autumn food source.

                                                            (Do I look like a wasp?)

Both species are sometimes referred to as wasp mimics because of their superficial resemblance to certain species of wasps. One can assume this provides them a measure of protection from predation from potential predators that may not be keen on eating a wasp. After all stings hurt, and a good sting to the mouth would be even more reason to avoid them.

PHB are found in the Eastern United States with records from New Mexico as well. They reach lengths up to 20 mm and are a welcome site to anyone who loves bugs as they are often one of the first species spotted in the spring after a cold, long winter of no bugs. In my case they were a beautiful winter visitor which was fine with me. I know they are harmless and will not bite or chew on any wood furniture or woodwork in my house. 

PHB was first described by a man by the name of Charles Joseph Gahan in 1908. Gahan was born in Ireland and went onto become the Keeper of the Department of Entomology at the British Museum of Natural History. His specialty was beetles in the family Cerambycidae. He originally classified the PHB as Cyllene Caryae and it was later changed to it's current scientific name.

Sunday, March 1, 2015

Red Velvet Mite

Red Velvet Mites in the family Trombidiidae include more than a 1,000 species Worldwide. They are classified as arachnids, but differ from spiders in many ways. Spiders possess 6 or 8 eyes, mites only have 2. Spiders have two body segments, whereas mites have only one. Mites also have a unique leg arrangement. There are two legs located in four separate sections on the underside of their body. There are many other differences which are too technical for me, but suffice it to say, while related, they are like distant cousins on the spider family tree.

They are sometimes called rain bugs as they are active after heavy rains especially in the early spring or fall. The one pictured here was found after a spring rain while mushroom hunting. It was actively hunting for prey on a rotting log. I knew it was a velvet mite, but had no idea its identity beyond that. It is next to impossible to differentiate one species from another without a microscope with exception to a few Palearctic species like the giant red velvet mite (Trombidium grandissimum). This particular red velvet mite is found in India, and may reach lengths up to 1/2 inch. This species is a true giant in the mite world where most species are nearly microscopic in size. They get their common name of red velvet mite from the fine red hairs all over their body which resembles velvet and gives them the ability to sense their surroundings. In addition to using those fine body hairs, they also sense their environment through vibrations and pheromone responses. Their front legs aid in guiding them through the habitats where they live by acting as a sensory organ. Having only 2 eyes gives them a serious disadvantage in the eyesight department, so instead they rely on delicate vibrations and pheromones that cue them in on food and mates. The bright red color warns potential predators that they taste bad and therefore they have few enemies with exception to their own kind which may cannibalize them. The 2nd stage nymphs have also been known to parasitize them.

Even though they taste terrible, it seems humans have found a use for them in medicine. Oils from some species, like the Giant Red Velvet Mite are used in traditional medicine to treat paralysis. In some cultures they are used as an aphrodisiac, earning them the name of "Indian Viagra." They are also used in a treatment to improve the immune system. Like any creature that finds itself useful to humans it can often be removed from the environment in such drastic numbers as to affect the overall balance of the ecosystem where they were found. Red Velvet Mites are an integral part of the ecosystem as a biological control agent feeding on harmful arthropods such as spider mites, spring cankerworm, cabbage moth, lace bug, and other arthropods that may damage crops. As nymphs they act as ecto-parasites and also control many harmful insects.

Mating between red velvet mites is an involved process which includes the male performing a bit of a dance to impress the female. He will deposit a spermatophore nearby on a small twig, piece of bark, or blade of grass. He then forms a chemical trail made of silk that he guide her across, essentially walking her to his "gift." If she is receptive to his advances she will position her body on top of the spermatophore and remain there until she has taken all his sperm into her body, becoming impregnated. If another male happens upon this scent trail he will follow it to the spermatophore and break it open, he will then leave his own spermatophore in place of his competitors. Essentially ensuring his genes are passed on without all the work of finding the female, dancing his 8 tiny legs off, and walking his female to his present. What a lazy little trickster!

The female will lay her eggs, from 60-100,000 depending upon species, in the soil, leaf litter or other organic matter. When the eggs hatch the newly born pre-nymphs stay very close to the area where they were born. After a few days they leave and take on the life of an ecto-parasite feeding on various arthropods, including grasshoppers, crickets, arachnids, aphids, etc. (pictured: mites feeding on Harvestman)

In most case their feeding does not kill the host, but in some cases their numbers are so large the host cannot survive. The next stage, called protonymphs   are calyptostatic and develop inside the cuticle of the larvae. They lie inactive like a pupa. After emerging from the cuticle of the host they now possess eight legs and are more active hunters, searching out prey, rather than attaching themselves to a host. They generally complete their lifecycle and become adults in the fall. It is common to see them after the first heavy rain in autumn. Any eggs that hatch in the late summer or early fall will not have time to complete their lifecycle to adulthood. Those individuals will overwinter and complete their lifecycle the next year or in some cases the following year.

These fuzzy little arachnids are common, yet rarely seen, brightly colored, yet harmless to humans, voracious predators, yet excellent biological pest control. When the spring rains return, head to the timber and search for these unique, fascinating, brightly colored arachnids as they hunt for food and mates among the forest floor. These tiny mites are a true treasure of the woodlands.

Thursday, October 16, 2014

Dotted Wolf Spider

This beautiful pin-striped spider is a Dotted Wolf Spider (Rabidosa punctulata formerly Lycosa punctulata). There are over 2300 species of wolf spiders Worldwide, making them one of the most common spiders in the World. This species is found throughout most of the United States. Autumn is the best time to find spiders as they have reached their adult size and are much more visible. Rest assured they were always present, just not easily seen in their juvenile state. Wolf spiders are some of the most easily recognized spiders in the Missouri. They are almost always large and often furry looking. Which often results in them being mistaken for tarantulas. While we do have tarantulas in Missouri, they only occur in the southern portion of the state. The Missouri River seems to be a barrier for them and they are not found in the northern part of our state.

        (Missouri Tarantula)                                                                        (Wolf Spider)

Wolf spiders however are found all over Missouri; there are five species of wolf spiders within the genus Rabidosa in North America. Dotted wolf spiders are not especially furry-looking like many other wolf spiders tend to be, but they are distinctive in other ways.

(Wolf spider in the genus Tigrosa carrying her babies)

                                                      (Wolf Spider that may be Hogna frondicola)

Dotted Wolf Spiders have bold stripes and a light golden color that sets them apart from most wolf spiders in other genus'. This also makes them rather dashing looking. They also have a series of spots or "dots" on the underside of their abdomen, if you can manage to see them.

Spiders differ from insects in some very obvious ways, insects have 3 body parts (Head, thorax and abdomen) whereas spiders have two body parts (cephalothorax (head and thorax combined into one part, and the abdomen). Insects posses 6 legs and spiders 8. All spiders posses venom and only a few insects do, all spiders can spin silk, only a few insects do. Spiders are meat eaters and do not feed on vegetation. Insects run the gambit of food preferences.

Spiders have unique eyes; most possess 8 eyes with a few exceptions like brown recluses which possess 6 eyes. Most spiders have poor eyesight, but spiders like wolf spiders have exceptional eyesight for their size. Wolf spiders are night time hunters and rely more heavily on their eyesight than do other spiders which rely more on their sensitive sense of touch (in their legs).
8-eyed spiders possess two direct sighted eyes, that are usually dark in color and very visible to the human eye, as pictured here (above right). The smaller, or indirect eyes are not as easily seen by us. These eyes usually have a layer of light reflecting crystals. This reflective quality allows them to see better in low light situations, which is a necessity  if you are a night hunter. Because of the reflective quality of their eyes they will glow when you shine a flashlight on them. This is a fun activity to do with your children. Grab a flashlight and head outside and let the kids shine the light in the grass and look for the "glowing eyes." It will amaze you to see just how many spiders are hunting in your yard.

Wolf spiders produce silk but do not use it to spin webs like orb weavers and many other spiders do. Instead the silk is used to spin egg sacs, to protect spiderlings and to capture food to save for later use. When she forms her egg sac she will carry it with her attached to the tip of her abdomen. When the spiderlings are ready to emerge from the egg sac it will change from a shiny bright white to a dark dirty brown.

 (Wolf spider in genus Tigrosa guarding her egg sac from a large predator....ME)

Then they will climb onto their mothers abdomen and ride around with her for awhile. She guards them temporarily until they are ready to be on their own. Usually a few weeks or so , but there are records of some spiderlings staying on their mothers back for up to 6 months. It is not uncommon to see a female traveling with her brood on her backside late in the summer or early fall. This burden may consist of 50 or more babies. Life span for these spiders is two years or so

Their habitat is typically woodlands, cotton fields and other croplands, old buildings, and grasslands. They may also be found near ponds or in old rodent burrows. Look for them near garbage piles, rock piles, log piles, or within holes in the ground. It is reported that wolf spiders can act aggressively towards humans. I really do not like the term aggression when describing an animals reaction to humans. I prefer defensive. Animals, be it a mammal, reptile or insect will defend itself. Often this defense involves a bite, and many fear a bite from one of these spiders, and it is reported to be painful. They do possess venom, as do all spiders, but the venom is not harmful to humans. It is designed to subdue and liquify their prey. The one photographed here did not exhibit any "aggressive" behavior towards me and I was able to coax her onto my hand for a photo. I handled her in a gentle manner and tried to appear as non-threatening as I could.

Wolf spiders are excellent hunters and typically rely on ambush techniques to capture a wide variety of small insects, including crickets, flies, ants, locusts, and other spiders. They may also run down prey. They help control insect populations, which makes them beneficial to humans. While they are excellent predators, they are often the prey. Small mammals, reptiles, amphibians and other spiders all feed on wolf spiders. There are even a group of wasps called spiders hunters that prey on spiders, especially wolf spiders, and uses them to feed their offspring.  In August I photographed a spider hunter capturing a rabid wolf spider. If you want to read about these amazing wasps the link is Spider Hunter.

                  (Spider wasp dragging a rabid wolf spider to her burrow to lay eggs on the paralyzed body)

 For another great article on this species visit my friend Eric Eaton's blog and read what he has to say about this species.....Bug Eric

Thursday, October 9, 2014

Spider Hunter

Spider Wasps in the family Pompilidae are a cosmopolitan group of wasp with somewhere around 5,000 known species and subspecies Worldwide. As their name would suggest they hunt spiders. There is even a subfamily called Ceropalinae that are known to cannibalize their own kind.

While at Squaw Creek awhile back I saw something small, quick and moving erratically across the road in front of me. This begged to be investigated, so I pulled the car over and found this largish wasp dragging a paralyzed spider from one side of the road to other. I couldn't help but feel somewhat sorry for this poor spider. He was stung, paralyzed, drug across the ground, then across the asphalt and was destined to be a meal for a hungry wasp grub. It is highly doubtful that the spider has any cognitive thought, and that is certainly a good thing. To be aware of your paralytic situation and impending doom at the mouth of a hungry wasp baby and not be able to do a darn thing about it would be the stuff of nightmares.


My presence was casting shadows over the wasp and causing her some pause and she would temporarily leave her prey and wander away. A few minutes later she would return and drag the spider a few feet more and then in a very nervous manner she would depart again. This went on for quite some time and it took her more than 15 minutes to finally reach the other side of the road with her quarry. The spider was quite a bit larger than she was, so the fact that she could maneuver this spider at all is a feat in and of itself. The species of spider is a type of wolf spider called a Rabid Wold Spider (Rabidosa rabida). This particular spider would be very defensive and I imagine not an easy adversary to subdue. I would have loved to see her initial interaction when she discovered the spider and made the decision to use it as food for her offspring. I'm sure it would have been a sight to see.

In most cases the wasp will have dug a burrow prior to hunting for a spider to provision it with. Occasionally though she will dig the burrow after finding her prey. Once she has maneuvered the spider into the burrow she will lay an egg on the abdomen of the spider and then close up the burrow entrance to protect her offspring from predators. When the egg hatches the wasp grub will feed on the paralyzed spider. They will leave the vital organs of the spider until right before they are ready to pupate, this way the spider does not perish before the wasp larvae is done growing. Once the wasp larvae has reached its full size it will form a silken cocoon and pupate. It will emerge the following spring. The size of the spider can determine the sex of her offspring. Larger prey generally produces larger reproductive females. From the size of this wolf spider I think it was destined to feed a female wasp grub.

Spider hunters are solitary wasps and therefore calmer and gentler by nature. They are only prone to sting if mishandled or mistreated. Colony nesting wasps such as hornets or yellow jackets on the other hand tend to be more defensive and more easily provoked. They are guarding nests, queens, offspring and food stores. With so much to defend they need to be on their guard. Whereas solitary nesters like spider hunters are not guarding anything. Once the eggs are laid the offspring are on their own and survival is all up to luck.

Wednesday, October 8, 2014

Imperial Moth

Imperial Moths (Eacles imperialis) in the family Saturniidae are large silk moths commonly found in forested areas throughout Missouri. They are also often found in suburban areas, especially near lights at night. The biggest one I ever found was at a gas station/convenient mart on the outskirts of St. Joseph.
Their range includes most of the Eastern United States from Nebraska to Maine. There are some reports that they are declining at an alarming rate in the northeastern part of their range. The population decline in these locations could and probably is due to habitat loss. Throughout the rest of their range their numbers are secure to abundant. The adults are large with wingspans up to 5.5 inches and are yellow with variable lavender spots. Males are smaller than females.

These large moths do not feed as adults, instead they get all the nutrition they need as caterpillars. If you've never seen one of these in their larval form, it is truly impressive. When hatched they are barely visible and possess an incredible appetite.

 They feed voraciously and reach lengths up to 3 or 4 inches when ready to pupate. They manage this in the span of several weeks.  It has been said that if a human baby gained weight like a caterpillar, they would weigh as much as a hippo in a single weekend. They feed on a wide variety of tree species like oak, hickory, walnut, pine, maple (including box elder), Norway spruce, sassafras, sweet gum and many others.

Moths are covered in furry scales that protect them from cooler nighttime temperatures. These large moths take it to a whole new level with what appears to be a winter-weight coat, complete with scarf and leg warmers. After midnight the females will begin signalling for males by emitting a pheromone. The males are capable of "smelling" the females from distances of more than a mile. He uses his large, feathery antennae to home in on her scent. Females will lay eggs one at a time, or up to 2 to 5 on the leaves of host plants. Eggs hatch in a couple of weeks. When ready to pupate they will move to the base of the host tree and burrow into the ground to pupate for the winter.

Naturalist Gene Stratton Porter wrote about the Imperial Moth in her novel "A Girl of the Limberlost" It was a prominent character in the plot development of the novel. She had a life long love of silk moths and shared her passion for their beauty in the book Moths of the Limberlost.

Monday, October 6, 2014

Differential Grasshoppers

Differential Grasshoppers (Melanoplus differentialis) are probably one of the most common of all the grasshoppers in Missouri. They have a distinguishing herringbone pattern on their hind legs, and are various shades of olive green with yellowish hind legs. They will range in size from 1 1/2 - 2 1/2 inches.

They are found in a wide variety of habitats, including meadows, tall grassy areas, backyards, gardens, open fields and along stream sides. The nymphs and adults both feed on various grasses and crops, including corn, soybeans, alfalfa, cotton, vegetables, fruit trees, and other small grains.

These grasshoppers have many predators, which include birds, toads, frogs, raccoons, opossums, turtles, bats, praying mantids, red fox, dragonflies, yellow jackets, fish, shrews, lizards, chipmunks, squirrels, spiders, centipedes, crickets, beetles, and the neighborhood cat. The larvae of the Blister Beetles use the eggs of grasshoppers as their primary food source.

Mating occurs in late summer and early fall. The females will press long eggs masses into the ground, near weeds. She may lay up to 8 egg masses each containing about 25 eggs. The eggs will overwinter and hatch the following spring. The newly born nymphs look very much like the adults. They will shed their exoskeleton (outer skeletal skin) several times over a course of two months before reaching adult size (picture 3). It is common to see these shed skins hanging from branches or grasses. Looking very much like they were scared right out of their skin and left it behind

Sometime in the fall when the temperatures begin to drop, and the first freeze hits, the adults will perish. Often time frozen right to the spot that they had been clinging to. It is almost eerie to come across one of these dead grasshoppers, it is almost like some mass weapon of destruction came through and freeze-dried them. (Below)