Saturday, June 27, 2015

Bess Beetles

Bess Beetles (Odontotaenius disjunctus)  in the family Passalidae are one of almost 500 species within this family of beetles. They are found from the Central United States and eastward. Most beetles within this family are found in the tropics, with only a few found within the United States. This particular species goes by many different common names including Peg Beetle, Betsy Beetle, Bess Bug, Patent Leather Beetle, and Horned Passalus. They grow quite large at over an inch in length, and with that horn on their face they can look very intimidating, but they are not known to bite.

These beetles are fond of old rotting stumps, and logs where they feed on the decaying wood. The boring or tunneling action they perform will create chambers where they will mate, lay eggs and rear young. 

These beetles have a unique life cycle, the female will lay eggs within rotting stumps or other decaying wood. Both adults will care for the young larvae. They feed their offspring bits of chewed up wood. It takes up to one year for them to complete their life cycle to adulthood. It is not uncommon for the adults to consume injured larvae.

(Bess Beetle Grub)
 (Bess Beetle Pupa)

 Both adults and larva are capable of making squeaky noises through stridulation, by rubbing their abdomen against their wings. This is a form of communication between adults. If handled they may stridulate loudly.

The newly emerged adults look different from mature adults in that they are reddish-brown in color instead of glossy black. As they age they will begin to look like black patent leather, which is where the common name of patent-leather beetle comes from. They often live in colonies within stumps,and seem to prefer oak, maple and other deciduous trees. The stump where I find them is from an old silver maple that died many years ago. The remnants of that stump have attracted many forms of wildlife from beetles, cockroaches, horntails, and snakes to name just a few of the things I've encountered while exploring. Logs and stumps where these beetles are active will decay rapidly, and nourish the soil with important nutrients. This activity is considered beneficial to humans by providing the necessary nutrients that trees and other plants need to thrive.  Many people would excavated and grind out an old stump. I prefer to leave them and see what shows up.

To learn more details about this beetle and their range be sure to check out this link for the University of Florida and their information page on this beetle. I am proud to say my image of the pupa is featured there.

Monday, June 22, 2015

Eyed-Click Beetle

Eyed Click Beetles (Alaus oculatus)
are some of the craziest looking beetles in the insect world. They are very large at nearly 2 inches in length.  The salt & pepper markings set them apart from other insects, not to mention those large "eyes." The false eyes make them look so intimidating, or funny depending upon your point of view. The first time I ever spotted one of these it gave me a start, I'd never seen anything like it. I scooped it into a jar to show my nephew that was going to be visiting later in the day. I retrieved the jar to show him and discovered the beetle had died! I opened the lid and peered in at the beetle, it was at this exact moment this little faker decided to come back to life. When he flipped his body straight up, narrowly missing my nose which was still in the opening of the jar....I almost had cardiac arrest! Needless to say I screamed, nearly dropped the jar, which in turn made my nephew scream. Then we both had a good laugh at my expense.

This was my first introduction to this beetle. I let the little trouble maker go, deciding I wanted nothing more to do with a beetle that could practically scare me out of my britches.

 My brother-in-law captured one shortly after my heart pounding experience that he had found at the farm. He grabbed it with his hands and discovered that they can give a painful pinch when they feel threatened. Apparently being grabbed by a giant alien causes them to feel sufficiently threatened to give a bite. He said it drew blood and hurt for quite some time. Lesson learned......don't grab with bare hands. So if the eyes don't scare u, the back flip will. If that doesn't work they will nip you if mishandled.

There are many different species of click beetles, and many do not have these distinctive eye spots. In fact most are drab in color like this brown specimen found in my garden hiding on the petal of a purple coneflower. 

There are approximately 800 species of click beetles in North American. All click beetles have a special mechanism on their lower body that allows them to flip themselves over if they find themselves belly up. Flipping over on your back is an effective way to play dead which may deter predators. Once the potential danger has passed they flip themselves back over and away they go about their business.

 Look for the eyed click beetle near decaying wood. They use this as hiding places. The adult females will deposit eggs in the soil near decaying wood. The eggs hatch and the larvae will crawl underneath the bark of rotting wood or burrow into the soft pithy part of old timber. The larvae of click beetles are called wireworms. They get their common name wireworm from their elongated shape and hard exoskeleton. They feed on the grubs of other beetle species. Wireworms may take up to 10 years, depending upon species to complete their lifecycle into adult beetle. 

Many species of wireworms feed on plants, including some crop species, but those of the eyed click beetle are strictly meat eaters and feed  on many harmful wood boring beetle larvae. Since eyed click beetles take two to five years to complete their life cycle, depending upon temperatures and other factors, this gives them much time to consume tons of beetle larvae. These insects are considered highly beneficial to foresters and gardeners. Adults they may take some nectar from plants but don't seem to require much in the way of food.