Thursday, December 26, 2013

Elderberry Borer Beetle

The Elderberry Borer or Cloaked Knotty-Horned Beetle as it is sometimes referred to (Desmocerus palliatus) is found in North America from Oklahoma to the Appalachian Mountains. They are found more often in the northern portion of their range in marshy, swampy areas where their host plant, elderberries, occur. This small to medium sized beetle reaches lengths up to 26 mm without antennae. They are a gorgeous colored beetle with iridescent bluish wings and  a vibrant yellow or yellow-orange band across the upper portion of the wings. The middle segments of the antennae have distinct knobby points which earned them the common name of Knotty-Horned Beetle or Cloaked Knotty-Horned Beetle. They are unmistakable and not to be confused with any other species as no other beetle carries such vibrant, unique colors and pattern.

A couple of years ago I became acquainted with a woman named Annie Ray who did her doctoral work on beetles in this genus. Her project was centered around the pheromones produced by the female of this species and how the male homes in on her scent. As part of the research we had to dig down into the roots of the elderberries and break open the root masses looking for larvae or pupae.

The objective was to find them in this stage, because when they were located as adults they would not work for her research purposes. In essence she needed the virginal females. This all sounds easy in theory, but I assure you in practice it is much more difficult than you would expect. We were working in 90 degree temperatures often in full sun. We had experienced recent rains, which made one of our locations extremely muddy and digging in soppy, water-logged soil was pure torture, especially with the beating sun baking your skin. I became very adept at using shovels, spades, axes and limb loppers.
 Careful was the word of the day. It was all too easy to accidentally cut a larvae or pupae in half. This was enough to bring you to tears, to have worked so hard to find one, only to realize you destroyed it before you could get it out of its pupal chamber. Often we would work for as much as an hour before finding a single specimen.

Each discovery brought excitement. It really is true that the things we work the hardest for bring the greatest joy, because each time we found one of these elusive larvae or pupae you would have thought we struck gold at the amount of excitement we expressed. Annie spent three days here in NW Missouri working at several different locations, including Squaw Creek NWR, where she was given permission through an application process to search for these beetles on the refuge. All told she went home with 7 specimens. Not near the number we were hoping for, but ever the optimist she was grateful to not have been completely skunked. The beetles were safely ensconced in vials and packed for airplane travel to Ohio. From there they were to be shipped to California to her research assistant to begin extracting pheromones from.




Females of this species will begin "calling" for males as soon as they emerge from their underground pupal cell. Males come from great distances drawn by her scent and mating takes place immediately. We were certain that each adult we found had already been mated because of how rapidly this activity takes place once the females leave their pupal chamber. Females lay their eggs at the base of elderberry bushes, and the larvae will burrow into the roots or stem bases to feed. When they are ready to pupate they will travel to the soft, pithy parts of the branches, often near the roots and form a pupal cell. They emerge in early spring. Timing is everything when you are seeking to find these beetles before emergence. Literally it had to be timed so that we were digging and searching a few days prior to when we thought they would be coming out of their underground chambers. Once the adults are plentiful, your window of opportunity is gone.

These beetles are not known to cause any significant damage to the elderberry bushes. They do not occur in large enough numbers to wreck havoc. As adults they feed on the pollen in spring.Finding these beetles is not always easy, but once you've found one they are sure to leave an impression with their beautiful color and substantial size. Look for elderberries in full bloom in the spring and with any luck you will be awarded with the sight of one of these gorgeous beetles.


Tuesday, December 3, 2013

Mayfly

Mayflies are not actually flies at all. They are insects in the order Ephemeroptera and the family Ephemieridae, which translates into "short-lived" and likely eludes to the very short lifespan of these insects.

How do we know if something is a fly or merely called a fly? Here is an easy way to tell the difference, if the name is all one word like Mayfly, Dobsonfly, Caddisfly, Dragonfly, Damselfly, etc.. then it is definitely NOT a fly, but rather belongs to some other order of insect. If the insect has a first and last name like House Fly, Bot Fly, Flesh Fly, Flower Fly, Robber Fly, Bee Fly....etc. Then it definitely IS a fly.

They are one of the most commonly seen insects at porch lights in early summer or sometimes fall.
 The species I see more often than any other is the Burrowing Mayfly. They are also the largest species of mayfly in Missouri, reaching lengths up to 1 1/2 inches. Most mayflies are found in the Eastern United States, with only few species being found out west. It is not uncommon to have dozens of these at porch light in June, or in the case of this youtube video hundreds of thousands swarming a pole. Check out this Mayfly emergence.

The Burrowing Mayfly, also known as the Golden Mayfly, is a beautiful shade of golden-yellow with pale bands across their abdomen (pictured below).As they age their coloring will become darker.


The lifecycle of a mayfly begins underwater as a nymph with seven pairs of gills. They live in the bottom sediment of streams, slow moving rivers, ponds and lakes. The nymphs feed on sediment, diatoms and several species are predatory and feed on other aquatic insects. After numerous molts (skin sheds), they will emerge approximately one year after hatching in the water. The males typically appear first, as subimago adults,meaning they are not completely formed adults yet, they will shed their skin one more time before completing their lifecycle to adulthood. These subimago's are a favorite food of trout and are often used by fisherman as bait. Trout fishermen also use mayflies as a model for the flies that they tie for bait. Mayflies are the only group of insects to have this subimago stage into adulthood. As a subimago they do not fly well, cannot reproduce and lack the coloring of the adult form that would attract a mate. Within 24 hours after emerging they will shed and become full fledged adults capable of breeding. Females emerge shortly after males and also shed their skin for the final time. Mating occurs within hours of emerging.


Time is of the essence, when you only live a day or two, or perhaps only mere minutes (for some species) there is no time to waste on frivolity. Soon after mating, the female will drop her eggs upstream in the water, the current will softly carry the eggs downstream and deposit them on the substrate in the bottom of the stream. If the eggs are laid in lakes or ponds she will drop them wily-nily on top the water, and the eggs sink to the bottom. In some parts of the world the emergence of mayflies is a sight to behold, they all seem to appear at once in a mass exodus. Millions of mayflies rising up out of the water in one large swarm, landing on every available surface may seem like a nuisance to many humans, but these little insects serve a major role in the lifecycle of other species. Mayflies are not only consumed by trout and other fish, but birds, frogs, toads, and other insect eating creatures get in on the all-u-can-eat buffet of mayflies as well.

                                                         (Jumping spider eating mayfly)

I am not sure of the species of this mayfly pictured below on the Sage, but it is a beautiful shade of russet and is much smaller than the Burrowing Mayfly at only 3/4 of an inch in length. 
Although their large numbers can be intimidating, they are completely harmless to humans. They cannot bite, in fact they do not have functioning mouth parts. This lack of mouth parts, also means they do not feed. Their only reason for existence it would appear is to mate, reproduce, and to be sustenance to other creatures. I did find a website that claimed they eat fruits and flowers, but in my opinion this would be fallacy. I know of no mayfly that has the ability to eat, nor do they live long enough to worry about eating even if they could. I would be curious to see what the experts have to say. This is just one example of how much mixed information is out there on the web and it pays to do numerous searches before settling on the truth about something.