Archive for the Virginia Category

IN SEARCH OF A HOLY GRAIL

Posted in Butterflies, Flies, Insects, Virginia on August 22, 2011 by Dr. Art Evans

By Arthur V. Evans

Last week, on a drizzly Thursday morning, I drove out to Cherry Orchard Bog Natural Area Preserve with my friends and colleagues Anne Wright and Paul Bedell. Straddling a power line right-of-way near the Sussex-Prince George County line, this preserve features a coastal plain acidic seep that supports an amazing assemblage of rare plants, some of which bloom in late summer.  The Virginia Natural Heritage Program staff uses prescribed burns here to prevent trees, shrubs, and woody vines from choking this open wetland, and to restore and maintain this rare plant habitat. However, after yet another extended summer drought here in Virginia, surface water was nowhere in evidence.

My goal was to photograph and collect late summer beetles, while Anne and Paul focused their efforts on odonates (dragonflies and damselflies) and robber flies (Asilidae). Few beetles were out and about, so I strapped on my camera gear and knee-pads and turned my attention to photographing other insects and spiders.

Several tall and luxurious patches of sweet-scented joe pye weed, Eupatorium purpureum, grew smack dab in the middle of the power line right-of-way. These nectar-rich flowers were magnets for all kinds of insects (other than beetles!), including several species of butterflies. A dozen or so each of large showy eastern tiger swallowtails and monarch butterflies flitted from blossom to blossom, occasionally unfurling their probosces to imbibe the flower’s sweet offerings.

I decided to head into the adjacent woods by following a fire line that snaked along the edge of a recent prescribed burn. I scanned the lush wall of vegetation that delimited the surrounding woods from the burn in hopes of finding multi-legged creatures. Nearly half an hour elapsed and all I had to show for my photographic efforts was a young Carolina mantid (Stagmomantis carolina) and a black-and-yellow garden spider (Argiope aurantia).

I saw a flash of shiny black wings among the foliage. My first thought was that it might be a mourning scorpionfly, but then it became clear that it was a female robber fly (family Asilidae) dining on a small wasp. I am no robber fly expert, but this particular fly reminded me of the genus Laphria, some of which are bee or wasp mimics.

Just as I was about to take a photograph, she was gone. Fortunately, I saw her land on a nearby leaf and she was still very much in possession of her lifeless prey. I leaned in to take the shot and, with the burst of my flash, she took to the air again. I watched intently as the shiny black fly flitted along the wood’s edge and landed on another leaf. Again, I slowly inched my camera toward her and watched her black shiny body fill up the frame of my viewfinder. And again, the flash of my camera caused her to fly away and into the burn area. I tracked her through several more landings on the low growth before she landed on a log. I took my third and last shot and she was gone. During the pursuit, a slightly smaller individual of the same species, possibly a male, also crossed my path.

I slowly walked all the way around the edge of the burn and back to the car, but saw no more robber flies. I told Paul that I had photographed what I thought to be a Laphria, but he said that the dark wings didn’t really fit any Virginia species in that genus. Paul would certainly know since he had recently published the first annotated checklist of the 115 species robber flies known to occur in Virginia (Bedell, 2010). I promised to post my best photo of the fly in question on my Facebook page as soon as I returned home.

Eric Fisher

Once posted, Paul suggested that it might be the very rare Orthogonis stygia, a species not yet known to occur in Virginia. I sent Paul all three of my images and he forwarded them to Eric Fisher for confirmation. Eric, a dipterist and asilid expert (and fellow alumni of Cal State Long Beach) quickly confirmed Paul’s identification and another new state record for Virginia.

Stanley Bromley (1931) first described this pompilid wasp mimic from three specimens collected in June; two of the specimens were from North Carolina and Mississippi, while the origin of the third specimen was unknown to him.  Another specimen was later recorded from Florida (Bromley, 1950).  Since then, specimens of this exceptionally rare species have been found in Alabama, Arkansas, Florida, Mississippi, Oklahoma, and Texas (Taber & Fleenor, 2003; Barnes et al., 2007).

Paul and I returned to the site only two days after I snapped my photos and searched several hours for Orthogonis. Although our efforts were in vain, we have not given up! Stay tuned for further developments

References

Barnes, J. K., N. Lavers, and H. Raney. 2007. Robber flies (Diptera: Asilidae) of Arkansas, U.S.A.: Notes and a checklist. Entomological News 118: 241-258.

Bedell, P. 2010. A preliminary list of the robber flies (Diptera: Asilidae) of Virginia. Banisteria 36: 3-19.

Bromley, S.W. 1931. New asilidae with a revised key to the genus Stenopogon Loew: (Diptera). Annals of the Entomological Society of America 24: 427-435.

Bromley, S.W. 1950. Florida Asilidae (Diptera) with description of one new species. Annals of the Entomological Society of America 43: 227-239.

Taber, S.W., and S.B. Fleenor. 2003. Range extension, habitat, and review of the rare robber fly Orthogonis stygia (Bromley). Southwestern Entomologist 29: 85-87.

For more information on robber flies visit:

Asilidae (Robber Flies) Page. A Page by Roy Beckemeyer <http://www.windsofkansas.com/Basilidae/asilid.html

Family Asilidae – Robber Flies <http://bugguide.net/node/view/151/bgpage>

Giff Beaton’s Robber Flies (Asilidae) of Georgia and the Southeast http://www.giffbeaton.com/Robber%20Flies.htm>

Robber Flies <http://hr-rna.com/RNA/Robber%20main%20page.htm>

Robber Flies (Asilidae) <http://www.geller-grimm.de/asilidae.htm>

The Robber Flies of Crowley’s Ridge, Arkansas. An Illustrated Guide by Norman Lavers http://normanlavers.net/>

Advertisements

ANOTHER RARE BEETLE ADDED TO THE VIRGINIA FAUNA

Posted in Beetles, Insects, Virginia on August 11, 2011 by Dr. Art Evans

By Arthur V. Evans

While sorting through some spring Malaise trap samples from the Bull Run Mountains Natural Area Preserve, I came across a single specimen of a soldier beetle-like insect five millimeters in length that was unfamiliar to me. It resembled a drawing that I had seen in Blatchley (1910) of Blanchardia gracilis (now Blatchleya gracilis: Omethidae).

I ran the specimen through the omethid key American Beetles (2002) and determined it to be Omethes marginatus LeConte. The specimen compares perfectly to LeConte’s type in the Museum of Comparative Zoology at Harvard University and represents a new species AND family record for Virginia. Omethes marginatus was previously known from Connecticut, Maryland, New Jersey, Ohio, and Pennsylvania; additional new state records include Arkansas and Indiana. Omethids of any stripe are rare in collections and little is known about their natural history.

References

Arnett, R.H., Jr., M.C. Thomas, P.E. Skelley, J.H. Frank, editors. 2002. Volume 2. American Beetles. Polyphaga: Scarabaeoidea through Curculionoidea. CRC Press: Boca Raton, FL.

Blatchley, W. 1910. An illustrated descriptive catalogue of the Coleoptera or beetles (exclusive of the Rhynchophora) known to occur in Indiana. With bibliography and descriptions of new species. Indianapolis, IN.

 

CALLING ALL CEPHALOON

Posted in Beetles, Virginia on March 10, 2011 by Dr. Art Evans

By Arthur V. Evans

In the early 1970’s I went on several family camping trips to Plumas County in California’s Sierra Nevada. My parents had purchased several acres of land bordered by a babbling stream that flowed out of Round Valley Reservoir located just outside the sleepy mountain town of Greenville. Here I spent many spring and summer days wandering along the trails and logging roads in search of all kinds of insects, especially beetles.

Meadow wildflowers bristled with species of lampyrids (Ellychnia) and lepturine cerambycids unlike any I had seen before. Freshly cut pine slash teemed with shiny metallic buprestids (Buprestis, Chalcophora, Dicerca) and cerambycids (Monochamus) sporting incredibly long antennae. Mating and feeding scarab beetles (Hoplia dispar) with their beefy back legs splayed out and sporting various colors and patterns clambered over one another among the blooms of buckbrush. The sunny shore along the reservoir and its associated paths and roads were bejeweled with emerald-green tiger  beetles (Cicindela tranquebarica sierra) that, more often than not, remained just out of reach. What a paradise for a budding young coleopterist!

Wolf lichen, Letharia sp. © 2002, Arthur V. Evans

On one of these trips, I was particularly fascinated by the various forms of lichen that festooned the granite boulders and conifer branches. I collected a small chunk of decaying wood clothed with the flourescent green wolf lichen (Letharia). The toxic yellow pigment of this fruticose lichen was used by ranchers to poison wolves and foxes and by Native Americans in dyes and paints.

Upon returning home, I placed that chunk of wood in a terrarium that consisted of a gallon jar supplied with a thick layer of moist, rich soil. After a few weeks, I noticed that a long, slender, leggy beetle had apparently emerged from the rotten wood and taken up residence in my terrarium. It resembled a somewhat homelier version of some of the beetles that I had collected on the meadow flowers. I didn’t know what to feed it and after a day or two it died. I carefully removed the beetle, mounted and labeled it, and placed the specimen among the other longhorn beetles in my collection. At that time my entire insect collection was housed in five cigar boxes. Even at this early stage of my entomological development, two-fifths of my collection (the King Edward and Swisher Sweets boxes) consisted entirely of beetles.

Several years later, I discovered that my terrarium beetle was not a longhorn at all. It was a false longhorn beetle in the genus Cephaloon. Cephaloon is currently placed in the family now known as the Stenotrachelidae, a small group of tenebrionoid beetles with 19 species distributed throughout the Holarctic region. Of the 10 species and four genera of stenotrachelids known in North America, five species occur east of the Mississippi River. The monotypic genera Anelpistus, Nematoplus, and Stenotrachelus all have northern, or boreal distributions, but the fifth genus, Cephaloon, ranges a bit more south in the forested mountain chains of the Sierra Nevada in the west and the Appalachian Mountains of the east. There are six North American species of Cephaloon,  two of which occur in eastern North America; two additional species are found in eastern Siberia and Japan.

Thomas L. Casey, Jr.  (1857-1925) divided the North American species of Cephaloon into three more genera. Edwin Van Dyke (1869-1952) considered Casey’s taxa as subgenera of Cephaloon. The North American species were later “revised” by the brothers Hopping (Ralph and George) and they relegated Casey’s taxa to synonymy. Ross Arnett, Jr. (1919-1999) reviewed the Nearctic and Palearctic species of Cephaloon. All of the species in this genus are slender, leggy, and somewhat broad-shouldered beetles that resemble lepturine cerambycids, resulting in the common name “false longhorn beetles.”

Stentotrachelids are relatively rare in collections. The short-lived adults are seldom collected in numbers and thought to feed on pollen. Species of Cephaloon are typically found during the late spring resting on flowers or vegetation during the day in montane deciduous and coniferous forests. They are collected by hand, or by sweeping and beating vegetation. Individuals are also attracted to lights at night or captured in Malaise and flight intercept traps. Based on the known biology of C. ungulare LeConte in eastern North America, the larvae of all species of Cephaloon are likely to develop in decaying logs infected with fungal rot.

Cephaloon lepturides Newman. ©2009, Arthur V. Evans

British entomologist Edward Newman (1801-1876) described the first species of Cephaloon, C. lepturides, in 1838 from a single specimen collected by Edward Doubleday (1811-1849) at Trenton Falls, New York. Doubleday was a well-known British lepidopterist and had undertaken a two-year insect collecting trip to the United States in 1835.

Newman originally placed Cephaloon among other genera for which he did not assign to a “natural order,” or family, but later placed it in the Oedemeridae. Russian entomologist Victor Motschulsky (1810-1871) placed it in the Melandryidae. John LeConte (1825-1883) initially thought that they were meloids, but later selected Cepahloon as the sole representative of his new family, the Cephaloidae. Over the years more genera were added to the Cephaloidae, the name of which was replaced by Stenotrachelidae in 1990 on the basis of priority by Finnish coleopterist Hans Silfverberg.

Little is known about the biology of Cephaloon. Their montane distributions and the saproxylic preferences of the larvae suggest their possible use as biological indicator species. Populations of saproxylic beetles are significantly related to parameters of forest structure and health. The impacts of current forest management practices on these and other saproxylic beetles, especially those that reduce coarse woody debris and fragment old growth forests, are poorly understood and need further study.

References

Arnett Jr., R.H. 1953. A review of the beetle family Cephaloidae. Proceedings of the United State National Museum 103 (3321): 155-161.

Casey, T.L. 1898. Studies in Cephaloidae. Entomological News 9: 193-195.

Evans, A.V. and J.N. Hogue. 2006. Field Guide to Beetles of California. University of California Press. Berkeley, CA. 334 pp.

Hopping, R. and G.R. Hopping. 1934. A revision of the genus Cephaloon Newm. Pan-Pacific Entomologist. 10: 64-70.

Lawrence, J.F. 1991. Cephaloidae (Tenebrionidae) (including Nematoplidae, Stenotrachelidae. p. 529. In Stehr, F.W. Immature insects. Volume 2. Kendall/Hunt Publishing Co. Dubuque, IA. 975 pp.

LeConte, J.L. 1862. Classification of the Coleoptera of North America. Smithsonian Miscellaneous Collections 3: 209-286.

Lawrence, J.F. and A. Slipinski. 2010. 11.17. Stenotrachelidae C.G. Thomson, 1859. p. 687. In Leschen, R.A.B., R.G. Beutel, J.F. Lawrence (editors). Handbook of Zoology. Arthropoda: Insecta. Coleoptera, Beetles. Volume 2: Morphology and Systematics (Elateroidea, Bostrichiformia, Cucujiformia partim).  De Gruyter, Berlin, Germany. 786 pp.

Majka, C.G. 2011. The Stenotrachelidae (Coleoptera) of Atlantic Canada. Journal of the Acadian Entomological Society 7: 7-13.

Majka, C.G. and D.A. Pollock. 2006. Understanding saproxylic beetles: new records of Tetratomidae, Melandryidae, Synchroidae, and Scraptiidae from the Maritime Provinces of Canada (Coleoptera: Tenebrionoidea). Zootaxa 1248: 45-68.

Newman, E. 1838. Entomological notes. Entomologist’s Monthly Magazine 5: 377-402.

Salmon, M.A. 2000. The Aurelian legacy. British butterflies and their collectors. University of California Press. Berkeley, CA. 432 pp.

Silfverberg, H. 1990. The nomenclaturally correct names of some family-groups in Coleoptera. Entomologica Fennica 1: 119-121.

Storer, T.I., R.L. Usinger, and D. Lukas. 2004. Sierra Nevada Natural History. University of California Press. Berkeley, CA. 438 pp.

Van Dyke, E.C. New species of heteromerous Coleoptera. Bulletin of the Brooklyn Entomological Society 23: 252-262.

Young, D.K. 2002. 110. Stenotrachelidae. pp. 520-521. In Arnett Jr., R.H., M.C. Thomas, P.E. Skelley, and J.H. Frank (editors). American Beetles. Volume 2. Polyphaga: Scarabaeoidea through Curculionoidea. CRC Press, Boca Raton, FL.  861 pp.

© 2011, Arthur V. Evans

A RARE BEETLE NEW TO VIRGINIA

Posted in Beetles, Environment, VCU Rice Center, Virginia on January 22, 2011 by Dr. Art Evans

By Arthur V. Evans

Xylophilus crassicornis Muona. © 2011, A.V. Evans

My insect survey at the VCU Rice Center continues to reveal species that are rarely collected and/or newly recorded for the Commonwealth of Virginia. While sorting through dozens of trap samples containing thousands of insects, I recently discovered three specimens of a rarely collected false click beetle (Eucnemidae), Xylophilus crassicornis. This collection represents the first records for the genus and species in Virginia.

Xylophilus crassicornis was first described by Finnish entomologist Jyriki Muona in 2000 from a single female specimen collected from Maryland in 1902. The specimen was located in the collection of the Entomology Department at Cornell University in Ithaca, New York. A second specimen from Alambama was identified last year. The VCU Rice Center specimens, the sex of which are yet unknown, measure 2.8-4.0 mm and were collected from Malaise traps in May that were placed just northwest of the administrative building and among the vernal pools off Kimages Road.

Malaise trap. © 2010, A.V. Evans

Although relatively little is known of their habits and distribution, false click beetles probably play an important role in the interactions between trees, fungi, and forest regeneration. Further study of their biology may suggest their use as important indicators of forest diversity.

References

Hoffman, R.L., R.L. Otto, and R. Vigneault. 2009. An annotated list of the false click beetles of Virginia (Coleoptera: Eucnemidae). Banisteria 34: 25-32.

Muona, J. 2000. A revision of the Nearctic Eucnemidae. Acta Zoologica Fennica 212: 1-106.

© 2011, A.V. Evans

TIPPING THE SCALES

Posted in Pests, Scale insects, Virginia with tags , , , , on September 19, 2010 by Dr. Art Evans

By Arthur V. Evans

Wax scales that is. Indian wax scales to be precise.

While trimming our nandina hedge this afternoon, I noticed a couple of small, white, barnacle-looking lumps on a stem. They were female Indian wax scales, Ceroplastes ceriferus (Fabricius). Sexing Indian wax scales is easy since males are not known in any wild population in Virginia. Adults are covered with a thick, white waxy layer that not only protects them from predators, parasitoids, and pesticides, but also helps them to survive freezing temperatures during the winter.

Reproduction is by parthenogenesis. One generation is produced annually in Virginia, but two or more appear in warmer climates. The first instars, or crawlers, hatch in spring and early summer and feed on leaves. They are not covered with a protective wax layer and are very susceptible to dehydration, parasites, and pesticides.

Adult Indian wax scales are conspicuous in late summer and early fall and suck sap from at least 122 plant species in 46 families. Prolific breeders, they quickly cover ornamental plants. Burgeoning wax scale populations not only ruin the plant’s appearance, but also cover them with sooty mold that develops on the prodigious amount of sticky waste (honeydew) that they produce.

Carefully tipping or lifting the scale to one side to detach the it from the plant stem reveals the orange and segmented body underneath. In the adjacent photo, the anterior of the body is on the lower right, while posterior is on the upper left. The mouthparts are visible and appear as a dark central spot at about the anterior third of the body.

Resource: Kosztarab, M. 1996. Scale Insects of Northeastern North America. Identification, Biology, and Distribution. Virginia Museum of Natural History, Special Publication No. 3. Martinsville, VA. 650 pp.

© 2010, A.V. Evans

A BEVY OF BUCKEYES

Posted in Butterflies, Insects, Virginia with tags , , , , , , on September 15, 2010 by Dr. Art Evans

By Arthur V. Evans

For the past month or so, Virginia has been awash with the Common Buckeye, Junonia coenia. The name Junonia is derived from the diminutive form of the Greek Juno, Zeus’ consort, while the specific epithet, coenia, comes from the Greek kionos meaning common. With six distinct eyespots on their wings, these handsome and energetic insects cannot be confused with any other butterfly species in the Commonwealth.

Their rapid, low, and somewhat erratic flight consists of fluttering strokes occasionally interrupted by meandering glides usually of no more than a foot off the ground. When alarmed, Common Buckeyes are capable of taking to the air in a rapid and sustained flight. They sip nectar from a variety of flowers and frequently rest in open, sunny spots in neighborhoods, parks, wetlands, fields, roadsides, and other open habitats with plenty of low-growing vegetation.

The orange-headed and metallic blue-spined caterpillars are highly variable in color and pattern. They feed on plants in several families and are especially fond of those in the snapdragon (Scrophulariaceae) and acanthus (Acanthaceae) families.

Although they occur throughout the United States, Common Buckeyes only persist in the frost-free southern and eastern halves of the country; individuals observed in the Great Lakes States, New England, and southern Canada are migrants. In eastern United States, these butterflies are in evidence throughout the winter in Florida and the coastal regions of southeastern and Gulf States.

© 2010, A.V. Evans

FALCATE ORANGETIPS

Posted in Butterflies, Environment, Insects, Virginia with tags , , , , , , , on April 5, 2010 by Dr. Art Evans

By Arthur V. Evans

After a few false starts spring has finally arrived here in central Virginia, and not a moment too soon. In hopes of seeing some examples of the early spring insect fauna, I recently set out on a warm, sunny day for the James River Park near the 42nd Street entrance.

The orange and slightly hooked wing-tips were the unmistakable field marks of the male falcate orangetip, Anthocharis midea, the only species of orangetip butterfly found in the eastern United States.

The latest floodwaters from spring rains had only just receded, leaving a thin and dusty film of silt and debris high above the river’s usual channel in the park. Just past the flood residue, small plants had raised their tiny blossoms high to lure the season’s first pollen- and nectar-loving insects.

As I wandered upriver toward the Nickle Bridge, a flash of white with a hint of rich orange crossed my path. It slowly yet deliberately flitted about the freshly emerged sprigs of green that populated the edges of the path before finally settling for just a moment or two on a small flower. The orange and slightly hooked wing-tips were the unmistakable field marks of the male falcate orangetip, Anthocharis midea, the only species of orangetip butterfly found in eastern United States.

The females lack the orange patch, but are otherwise similar in appearance to the males. The wings of both sexes are mostly white; the underside of the hind wing bears a finely marbled yellowish-brown pattern. From tip to tip, their wings span no more than one-and-a-half inches across.

Falcate orangetips are among the first butterflies to emerge from their pupae in spring. Widespread in Virginia, they are found in a variety of habitats, including parks, rocky mountain outcrops, open deciduous and mixed pine-oak woodlands, sandhills, and floodplain forests, especially along stream and river courses.

Females lay their greenish-yellow eggs singly on the flowers of various cresses and other members of the mustard family. The eggs soon turn red and hatch into ravenous larvae that devour mostly seed pods, buds, and flowers, and not leaves. Because of the limited number of reproductive structures on each food plant, larger caterpillars will not hesitate to eat their smaller brethren to reduce competition for meager food resources.

Mature caterpillars are green or blue-green and sprinkled with shiny dark plates bearing short bristles. A yellow stripe runs down the length of the back, while a broad white stripe runs from the head and along each side and meet on its backside. The winter is spent, sometimes two, as a narrow chrysalis that is sharply pointed on both ends.

Don’t hesitate to look for these attractive insects in an open woodland or bottomland forest near you. By early June the falcate orangetips will all be gone, and you will have to wait until the following spring for the next generation to once again make their brief and welcome appearance as heralds of spring.

© 2010, A.V. Evans

%d bloggers like this: