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Archive for June, 2012

Hummingbird Clearwing Moth

Of all the insects I’ve found in milkweed patches over the years, the Hummingbird Clearwing is one of my favorites. It is a species of sphinx moth, named for its habit of hovering at flowers while it gathers nectar with its proboscis in a manner similar to that of hummingbirds. In fact, they are often mistaken for hummingbirds. The transparent wings, light brown thorax and dark chestnut abdomen are the field marks to look for. A diurnal moth, the Hummingbird Clearwing can often be found during the day in milkweed patches.


Milkweed Visitors

Milkweed is in full bloom right now, presenting the perfect opportunity for young and old alike to discover the multitude of butterflies, beetles, bees and other insects that are attracted to these magnificent flowers. If you visit a milkweed patch, don’t leave before getting a good whiff of the flowers’ scent – one of the sweetest on earth. How many of the insects you find are carrying milkweed’s yellow pollen “saddlebags” on their feet? You might want to check out my children’s book, MILKWEED VISITORS, which I wrote after spending the better part of one summer photographing the various insects I found visiting a milkweed patch. ( http://basrelief.org/Pages/MV.html )


Liverworts

Liverworts, along with mosses and hornworts, are classified by botanists as bryophytes – non-flowering plants that lack vascular (conductive) tissue. It is possible, even likely, that liverworts were among the first plants to make the transition to life on land. Their appearance varies according to the stage in which you see them, but the plants we think of when we think of liverworts are very small (less than an inch in diameter and about 4 inches in length) and can be relatively flat, growing very close to the ground. Liverworts have two basic stages, the dominant one being the flattish, leaf-like gametophyte. It produces male sex organs (antheridia) which produce sperm and female organs (archegonia) which produce eggs. The stalked, fringed, palm tree-like structures in the photograph are egg-producing archegonia, and the stalked, lobed structures are antheridia. Both are less than an inch tall and are produced on the same plant (unlike 80% of liverwort species that produce their sex organs on separate plants). The sperm must reach an egg in order for fertilization to take place, and it usually does this by swimming through rain water or dew. Once fertilization occurs, the second stage of the plant, or sporophyte, develops. The sporophyte produces spores, some of which will grow into gametophytes and the cycle (called alternation of generations) will repeat itself.


Luna Moths

Yesterday’s post was, as you quickly guessed, an eyespot from the forewing of a Luna Moth, Actias luna, one of North America’s giant silkworm moths. With a wingspan up to 4 ½,” it is one of our largest moths. Markings that resemble eyes are found not only on moths, but also on butterflies, birds, fish and reptiles. When they occur on butterflies and moths, eyespots are usually on the wings and are thought to scare off potential predators as well as to direct attacks away from vital body parts. After emerging from their cocoons, Luna Moths live for only about a week, during which time their sole mission is to mate. Like many other ephemeral insects, Luna Moths have no mouthparts and thus, do not eat as adults. (The phenomenal number of Luna Moths this summer may, in part, be due to the mild winter we had, which allowed more pupae to survive.)


Mystery Photo

Whose “eye” is looking at you?


How Toads Breathe

Like all amphibians, toads breathe through their skin as well as with their lungs. When a toad is inactive the skin usually absorbs enough oxygen to meet its needs. During and after activity a toad often supplements its supply of oxygen by actively breathing air into its lungs. Unlike mammals, amphibians do not make regular and rhythmic breathing movements but bring air into their lungs spasmodically as the need arises. Air enters the toad’s mouth through its nostrils, and by raising the floor of its mouth, the toad forces the air into its lungs. (Photo is of an American Toad.)


Red Grasshopper Mites

The next time you’re in a field, stop and take a close look at a few of the grasshoppers you find there. Chances are great that you will see tiny, red mites on some of them. These Red Grasshopper Mites, close relatives of ticks and spiders, go through three stages: larva, nymph and adult. The larvae (6-legged) attach to the base of a grasshopper’s wings, where they suck the grasshopper’s blood. The nymphs and adults (both 8-legged) are free-living and feed on grasshopper eggs. Each Red Grasshopper Mite nymph requires more than two grasshopper eggs to become an adult. An adult male Red Grasshopper Mite requires three grasshopper eggs for reproducing, and each female, seven to eight eggs. After breeding, a female mite deposits up to 4,000 eggs. Entomologists believe that mites reduce grasshopper survival and reproduction dramatically.