In 2008 we began seriously looking for tiger beetles (family Cicindelidae) on Crowley's Ridge. So far we have found fourteen species, and think we still might find two or three more (twenty species have been recorded in Arkansas). Without close-focusing binoculars you miss the charm of these tiny creatures with out-sized jaws that run and fly along ahead of you when you walk on a bare rocky or sandy trail.
They spend the first one or two years of their life as a larva waiting at the top of its burrow with jaws cocked open to grab whatever small creature walks by. The larvae all look about the same, but because the hole this one has made is more than 6 mm wide, it can positively be identified as the especially large Virginia Big-headed Tiger Beetle.
Most tiger beetles come out during the day, but the Virginia Big-headed Tiger Beetle (Tetracha virginica) is one of two nocturnal species on Crowley's Ridge. Frustratingly, if I expose the flash for this night-time picture for the light background and orange legs and antennae, the beautiful metallic green of the body comes out as nearly black.
If I expose for the body, the background, legs and antennae are washed out. But if you click this picture up to large size (and wait a moment for it to snap into focus), you'll get a better idea of the body color.
Virginia Big-headed Tiger Beetle
When tiger beetles mate, the male clamps his huge jaws around a special notch at the back of the female's thorax, and then stays with her to make sure no other male mates with her.
The other nocturnal tiger, recognizable by the creamy patches on the rear end, is the Pan-American Big-headed Tiger Beetle (T. carolina). It is smaller than the Virginia, but shares the big head and massive jaws. On this one, a male, you can see the pads on the front feet which are also used in holding the female.
Here is the female (without the toe pads). This species is more brightly colored than T. virginica, but again the night-time flash (or at any rate, my night-time flash) does not do it justice.
Even this exposure only hints at how colorful it would be in bright sunlight. My question is: Since it spends most of its time underground, and only comes out at night, why is it so colorful? Who is ever going to see it?
Pan-American Big-headed Tiger Beetle
This gives a better idea of the color.
Or this.
The rest of the Crowley's Ridge tigers come out in the daytime. This is the Bronzed Tiger Beetle (Cicindela repanda). All identifications here come with the help of Pearson et al., "A Field Guide to the Tiger Beetles of the United States and Canada," Oxford, 2006. To begin with, a quick way to tell tiger beetles from similar looking ground beetles, is, the head with its bulging eyes, on a tiger beetle, is always wider than the thorax.
Bronzed Tiger Beetle
Bronzed Tiger Beetles are probably the commonest and most numerous tigers along the Ridge. They show perfectly the basic pattern of the Cicindela tigers, namely: A front maculation, which starts on the shoulder and comes down then turns inward, making a capital C (at least on the left side); a middle maculation, which comes in from the side, curves sharply down, then turns back towards the center; and a rear maculation which is sort of like a mitten with a thumb, then the main part on the tail.
It can be seen here that the maculations are more or less joined along the margin of the elytra.
Tigers are considered among the fastest running insects. If a bee or other flying insect lands on the ground near them they can rush over before it can take off, and rip it apart with their mandibles. They often feed on ants. The head capsule and jaws of an ant are still clinging to this tiger's antenna.
Tigers are preyed on by large robber flies, such as this Proctacanthus duryi, and also the larger tiger beetles sometimes feed on the smaller species.
Here is the Twelve-spotted Tiger Beetle (Cicindela duedecimguttata). They often run along side by side with Bronzed Tiger Beetles, and you must observe them very carefully to distinguish the two species.
They have the same basic pattern, but it is so reduced that the maculations have broken up into separate spots.
Of the front maculation only the shoulder spot, and another spot a little farther down, remain; of the middle maculation only a squiggle, and a spot just below it; of the rear maculation only a spot, then a teardrop at the end. Count these on both sides and you get the twelve spots.
This is the hairy-necked Tiger Beetle (Cicindela hirticollis). Its neck is really no hairier than that of many other tigers. You distinguish it from Bronzed because the capital C in the front curves sharply up at the bottom to create what some think is a capital G. Also the maculations have become much broader than those on the Bronzed. Just as with the Twelve- spotted, these scarcer tigers also need to be picked out carefully from the swarms of Bronzed Tigers. Note the jaws on this one.
Hairy-necked Tiger Beetle
Here the capital G can be seen more easily.
Tiger beetles are opportunistic feeders, catching their own prey, stealing the prey of wasps or other tiger beetles, or feeding on carrion. This Hairy-necked Tiger has just found a dead Oblique-lined Tiger (see below in the species descriptions) and begun eating it.
This is the Cow Path Tiger Beetle (Cicindla purpurea), a mixture of beautiful green and bronze colors. Of the maculations, only the middle squiggle and the tail lights remain.
They only need to turn around to shift the balance of green and purple
They are found on dirt or clay roads through open grassland or pasture land.
The Big Sand Tiger Beetle (Cicindela formosa) has the maculations so expanded they are almost taking up all the space.
All the maculations are joined along the margin.
The Big Sand Tiger Beetle is one of the larger tigers that are known to feed sometimes on the smaller tigers.
The Six-spotted Tiger Beetle (Cicindela sexguttata) is as common as the Bronzed, but never in such large numbers. It is a beautiful bright metallic green that shifts to blue from different angles.
The "six spots" are sometimes eight spots and sometimes no spots at all, but the two large spots about the middle on the outer edge of the elytra are usually present.
Most tigers are found in open areas on sandy or clay soils, but the Six-spotted is often found in the woods, either on paths through the woods, or, commonly, running along the tops of fallen logs in a sunny opening in the woods.
The Festive Tiger Beetle (Cicindela scutellaris) comes in many colors and patterns, but the Festive Tigers on Crowley's Ridge are mostly an unmarked metallic green with coppery lights in it.
A fresh specimen usually has a fuzz of hair on top of the head
Festive Tiger Beetle
A metallic-green Festive Tiger can walk away from you, make a turn against the light, and suddenly go purple (unlike the Six-spotted, which turns blue).
I took this picture of a Festive at Toad Suck in the center of Arkansas. This beauty must be the true Cicindela scutellaris scutellaris. I suspect our mainly unmarked green Festives up here in the northeast corner of the state are C.s.rugata, a race shown on the range maps for the southern part of the state, but perhaps they curve northward up the Mississippi River Valley as many insects seem to do.
The salient feature in the Oblique-lined Tiger Beetle (Cicindela tranquebarica) are the two lines just below the shoulder that come back at a forty-five degree angle towards the center of the back.
The Punctured Tiger Beetle (Cicindela punctulata) is out almost every month of the summer, and you will almost always see it, even when there are no other tigers around, but you will only see it in small numbers.
They generally appear black, but if you look very carefully at them from above, you will see a line of what look like tiny puncture marks going down each side of the join between the elytra. Click this picture up to large size (and wait a few moments for it to snap into focus) to see them clearly.
Sometimes the puncture marks are difficult to see. Another helpful mark is that the elytra often seem wrinkled, as if they are not quite inflated. Also the abdomen often seems particularly narrow and straight sided.
Another common species that, like the Punctured, is almost always present in small numbers is the Eastern Red-bellied Tiger Beetle (Cicindela rufiventris). This is a problem because it also is a small, black-appearing tiger, and you have to look carefully to separate the two.
It comes in different colors and markings but generally has two little spots (or short lines) about two-thirds of the way down the back, and close to the center line.
Usually, to be safe, you have to watch it for a while from the back, and eventually it will drop its bright red abdomen down.
They are quite variable in the amount of marking they have. This particular male is quite heavily marked, whereas that particular female has almost no marking.
This tiny little tiger is the Ant-like Tiger Beetle (Cylindera cursitans). Entomologists are always happy to find this species, which is located in small, widely separated colonies. On the Ridge we find them on the riverfront at the town of St. Francis in Clay County, and in the picnic grounds of the associated Chalk Bluff Natural Area.
Ant-like Tiger Beetle
Finally, species number fourteen on Crowley's Ridge is the pretty little Sandy Stream Tiger Beetle (Ellipsoptera macra).
When they sit still they can disappear from sight.
Here are a few more Arkansas tiger beetles which I may as well add on. This is the well named Splendid Tiger Beetle (Cicindela splendida), easily recognized by its metallic green head and thorax, and brick red abdomen.
It is common everywhere in Arkansas, except on Crowley's Ridge, where I can't seem to locate one. I'll keep trying.
Splendid Tiger Beetle
The Large Grassland Tiger Beetle (Cicindela obsoleta) is an impressive big tiger that flies with a loud buzz.
There is a small isolated population of them in Arkansas in the vicinity of Calico Rock in Stone and Izard counties. If you go there in September and October to look for them, you will find they are actually quite common on limestone glades.
The S-banded Tiger Beetle (Cicindela trifasciata) lives on the Atlantic and Gulf Coasts but is known to make occasional jaunts deep into the continent. I was on the Arkansas River at Toad Suck (8/30/06) when this one made a sudden appearance, let me get one despairing shot at it, then flew away forever. The narrow S mark on the middle of the back identifies it.
This spring (5/1/10) I was on a boat ramp on the Sulphur River in Miller Co., the extreme SW corner of Arkansas, when I saw not one but two S-banded Tiger beetles. As usual they flew before I could get close, but I got a somewhat closer picture which I can blow up with a bit more detail.
But this year (5/29/11) we were very surprised to stop by a small pond in the Flatside Wilderness in Saline Co., central Arkansas, and find the muddy margin of the pond swarming with tiger beetles, we estimated 60-100, and every one was an S-banded. This pond was small, neither salty nor sandy (thought to be requirements), and about 350 miles north of the Gulf. So we no longer know what to think about the movements of this animal. Footnote: 10/30/11, we revisited the spot and found at least one pair, and they were mating, so this seems to be an actual colony.
This pretty Coppery Tiger Beetle (Ellipsoptera cuprascens) was on the Toad Suck beaches on the same day (the last day of August) that I saw that first S-banded.
Coppery Tiger Beetle
Coppery Tiger Beetle. Now I need to try to get photos of Ghost Tiger Beetles and One-spotted Tiger Beetles to complete the species of Arkansas.
