Cicindela On-Line
by Cesare Iacovone

 

Home - Biology and Ecology- Morphology and Anatomy- Distribution - Italian Species - Species Checklist

 Gallery - People Author - My Collection - Links - Literature - Announcements

 

 

 

The family of Cicindelidae, also known as Tiger Beetles, are members of the suborder Adephaga within the Order Coleoptera. Adult tiger beetles are easy to recognize, they have big  compound eyes wich are wider than the pronotum, in most of the genera. Antennae are eleven-segmented, very filiform and inserted on the frons above clypeus and below the eyes. Legs are long and have five-segmented tarsi.  Other comon thing among the family are the long sickle shaped mandibles. 

Tiger beetles come in many colors. Some are plain black, but others are stunningly decorated in metallic green, brown, maroon, or purple, often with stripes or spots.

Tiger beetles vary in size. The smallest measures 6 millimeters, the largest measures up to 45 millimeters.

ADULT ECOLOGY

Tiger beetles live in very specific types of habitats like sand dunes near seashores , rivers and lakes, but also on sand dunes, sand pits and sand blowouts far away from water. Other species are found in various upland sites, like hill sides, rocky areas near roads, trails and forest openings.

In many sites we can find more species living together, but there is no compitition umong them, becouse of the different microhabitats in wich they live, also many species are separated seasonally and have different times of emergence and so adults live in different periods of the year.

The adults are not active during rainy or cloudy cold days, becouse they are heliophilic insects, this means that there activity is regulated by air temperature, humidity and light intensity. Infact more hotter it is and more difficult it is to capture them, due to their velocity. This is not true for nocturnale species like Megacephala, Omus ext. wich do not fly, and can be found with head lamps while they look for eating.  Usually tiger beetles prefer to run and fly when they are disturbed. To do this they jump up and open the elytra so the wings begin go out and become airborn.

In defence, many species of coleoptera produce oders that disturbs predator. Also in Cicindelidae we find this kind of tecnique, even if not so much complex,  like it is in closely-related Carabidae. This becouse cicindelids can fly to escape predators, wich can be robber flies (Diptera: Asilidae), dragon flys (Odonata) and also vertebrates like reptiles and amphibians, birds and mammals.

LARVA ECOLOGY

Larva of tiger beetles live in burrows digged in the ground perpendicular to the surface, the depth varies greatly, depending on the type of soil and to geographic location. The entrance has no cone, becouse the larva puts the material it digs up as far away as possible. The big mandibles are used to dig the burrow and they stay at the top, waiting for small insects to pass close enough for capture.

When you find a burrow it si not easy to see the larva becouse it has seen you arrive and goes to the bottom, but if you wait a bit you see it come up. They are very sensitive to vibration of the ground. The entrance not always is open becouse the larva closes it before molting, during pupation, aestivation, hibernation and other things, like after eating, in rainy days and other conditions that makes it feel safe.

 

 

 

 


HOME - Designed and produced by Cesare IACOVONE - cesare.iacovone@tin.it