The white beach tiger beetle (Cicindela dorsalis) can be found in the eastern and southern coastal regions of the United States, stretching from Massachusetts to Florida, and along the Gulf of Mexico from Florida to Texas. It is common to find them in light, sandy areas such as dry riverbeds. (Arnett, Jr. Ph.D., 1985; Grzimek, 1972)
As the common name implies, the white beach tiger beetle can be found in coastal areas with white sandy beaches. Cicindela dorsalis prefers a moderate climate with average temperatures above 15 degrees Celsius. These beetles also prefer a habitat with moderate to arid rainfall totals. (Dunn, 1998a; Dunn, 1998b; O' Toole, 1986)
Adult Cicindela dorsalis can reach 13-15 millimeters in length and can be identified by their long legs, large prominent compound eyes, and eleven-segmented, filiform antennae. Adults also possess bright orange-red hues on the anterior side of their bodies, metallic green legs, and predominantly white wings. Larvae are S-shaped, and have hooks along their abdomen to help keep them in place within their vertical burrow. (Arnett, Jr. Ph.D., 1985; Dunn, 1998a; Dunn, 1998b; Grzimek, 1972)
Female tiger beetles lay eggs individually into small depressions that are later enlarged into burrows by the larvae as they mature, passing through three larval stages, or instars. The pupal stage occurs following the third instar. The larvae are responsible for digging a pupal chamber adjacent to the burrow. The larva will lie on its back and gradually lose mobility in its appendages; eventually its exoskeleton will become a translucent and creamy-white pupa. The pupal stage usually lasts 18-24 days, during which time the pupa becomes darker. The adult Cicindela dorsalis emerges through a slight hole in the dorsal portion of the pupal case, a process which requires two hours to complete. (Drees Ph.D. and Jackman Ph.D., 1998; Dunn, 1998a; Dunn, 1998b)
Mating occurs on warm, humid days. Female tiger beetles lay eggs individually into small depressions that will later be enlarged into burrows by the larvae as it matures. Tiger beetles are only known to produce one generation per year. (Drees Ph.D. and Jackman Ph.D., 1998; Dunn, 1998a; Dunn, 1998b)
Female tiger beetles have sensitive hairs on their abdomens that detect moisture content in the soil. Appropriate soil conditions are essential to larval survival and development, so these hairs play a major role in the females selection of where to oviposit her eggs. (Drees Ph.D. and Jackman Ph.D., 1998; Dunn, 1998a; Dunn, 1998b; Grzimek, 1972)
After oviposition, there is no further known parental investment.
Cicindela dorsalis are "heliophilic", meaning they are inactive on cloudy and cool days. They regulate their activity based upon sunlight intensity, wind, humidity, and air temperature. Most species of tiger beetles become fully active at above 15 degrees Celsius. Both partially developed larvae and adults spend their nights and winters burrowed in the soil. Adult white beach tiger beetles prefer to avoid confrontations with other species. A common tactic is for them to zigzag in short bursts and then fly a short distance, 5 to 20 feet, away from danger. The form and color of the threat is not important, just its size and motion determines the flight response. (Drees Ph.D. and Jackman Ph.D., 1998; Dunn, 1998a; Dunn, 1998b)
This species detects is surroundings visually, and through ground vibrations.
Larvae wait in their burrows to ambush passing prey; their wide head helping to disguise the opening of their burrow. They will usually eat their prey at the bottom of the burrow unless it is too large to fit down the hole. A first instar larva needs at least one meal in order to molt into its second instar. Because instars two and three of require several meals during their development, serious competition for food develops between individuals whose burrows are close to one another. The larvae have adapted to this by having a long developmental period and an ability to feed over a twenty-four hour time period. (Dunn, 1998a; Dunn, 1998b)
Cicindela dorsalis larvae are commonly parasitized by members of Bombyliidae, and Tiphiidae. Adults are preyed upon by amphibians, reptiles, various insectivorous mammals, and many types of birds. (Dunn, 1998a; Dunn, 1998b)
Cicindela dorsalis is considered a beneficial insect, in both larval and adult stages, because they prey on other insects, such as many species of leaf beetles that destroy crop plants. (Drees Ph.D. and Jackman Ph.D., 1998)
Cicindela dorsalis have no negative affect on humans unless they are mishandled, in which case they tend to bite.
Populations of C. dorsalis are in no danger and have no special status.
Sara Diamond (author), Animal Diversity Web.
Bryan Crane (author), Southwestern University, Stephanie Fabritius (editor), Southwestern University.
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
an animal that mainly eats meat
Found in coastal areas between 30 and 40 degrees latitude, in areas with a Mediterranean climate. Vegetation is dominated by stands of dense, spiny shrubs with tough (hard or waxy) evergreen leaves. May be maintained by periodic fire. In South America it includes the scrub ecotone between forest and paramo.
the nearshore aquatic habitats near a coast, or shoreline.
in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
union of egg and spermatozoan
Referring to a burrowing life-style or behavior, specialized for digging or burrowing.
having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.
the state that some animals enter during winter in which normal physiological processes are significantly reduced, thus lowering the animal's energy requirements. The act or condition of passing winter in a torpid or resting state, typically involving the abandonment of homoiothermy in mammals.
An animal that eats mainly insects or spiders.
fertilization takes place within the female's body
A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.
having the capacity to move from one place to another.
the area in which the animal is naturally found, the region in which it is endemic.
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
offspring are all produced in a single group (litter, clutch, etc.), after which the parent usually dies. Semelparous organisms often only live through a single season/year (or other periodic change in conditions) but may live for many seasons. In both cases reproduction occurs as a single investment of energy in offspring, with no future chance for investment in reproduction.
reproduction that includes combining the genetic contribution of two individuals, a male and a female
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
Living on the ground.
movements of a hard surface that are produced by animals as signals to others
uses sight to communicate
Arnett, Jr. Ph.D., R. 1985. American Insects: A handbook of the insects of America north of Mexico. New York, New York: Van Nostrand Reinhold Company.
Drees Ph.D., B., J. Jackman Ph.D.. 1998. A Field Guide to Common Texas Insects. Houston, Texas: Gulf Publishing Company.
Dunn, G. 1998. "Biology of Tiger Beetles" (On-line). Accessed April 18, 2001 at http://members.aol.com/YESedu/biology.html.
Dunn, G. 1998. "Ecology of Tiger Beetles" (On-line). Accessed April 18, 2001 at http://members.aol.com/YESedu/ecologyt.html.
Grzimek, B. 1972. Grzimek's Animal Life Encyclopedia Vol. 2: Insects. New York, New York: Van Nostrand Reinhold Company.
O' Toole, C. 1986. The Encyclopedia of Insects. New York, New York: Facts on File Publications.