Arthropods – Page 5 – Wandering through Wadis

Unlike the Egyptian Flower Mantis, the Black Cone-headed Grasshopper (Poekilocerus bufonius), with its large black body and slow movement, is easy to spot! Especially when they are resting on the rocks.

But these grasshoppers feed on plants in the milkweed family, which produce toxic chemicals. Ingesting these plants make the grasshoppers poisonous and distasteful to predators. When they are attacked, Black Cone-headed Grasshoppers spray a toxic fluid in defense. In Arabic, they are called zagat, meaning “the one who sprays toxins onto girls’ faces”.

You’ll most often find these grasshoppers on Pergularia tomentosa plants. Many Bedouin, before sitting down near one of these plants, will throw stones at the bush to scare off any grasshoppers. Sometimes these plants will be home to many grasshoppers. How many can you count in the picture below?

I’ve also spotted Black Cone-headed Grasshoppers on ajram (Anabasis sp.), harjal (Solenostemma arghel), reseda (Reseda sp.), broom (Retama raetam) and other plants.

The adults that I’ve seen have been between 6 – 10 cm in length. They are black or dark-colored, sometimes with yellow spots. I’ve noticed orange underwings on several.

Females are substantially larger the males, as you can see in the photo of the mating pair below.

As is typical of this order of insects (Orthoptera), the grasshoppers go through incomplete metamorphosis. The young nymphs resemble the adults but have no wings and can have extremely different colors. Look at these beautiful yellow ones!

As they age, they will shed their exoskeletons several times, growing wings until their final molt into a mature adult with fully-developed wings.

I’ve spotted Black Cone-headed Grasshoppers from late fall through spring in many of the wadis around Dahab, as well as higher up near Wadi Arada (on the way to St. Katherine’s). They are one of the first critters we came across on our early wadi wanderings and I always enjoy seeing them. And photographing them! They stay so still for so long, making excellent models. 🙂

References:

Aly, D. & Khalil, R. (2011). Wildlife in South Sinai. Cairo.Funded by the E.U. in cooperation with G.O.S.S.

Zalat, S. & Gilbert, F. (2008). Gardens of a Sacred Landscape: Bedouin Heritage and Natural History in the High Mountains of Sinai. Cairo: The American University in Cairo Press.

The Egyptian Flower Mantis (Blepharopsis mendica) is also known as the Devil’s Flower Mantis, Thistle Mantis, and Arab Mantis, but of course, I like the Egyptian name. 🙂

These mantids are referred to as Praying Mantises because of the way they hold their forelegs folded in front, as if in prayer. Mantises are also characterized by their triangular heads and forward facing eyes.

Spring is the perfect time to spot these mantises in our desert wadis. Specifically, to spot the nymphs. After hatching from their egg, mantises continue to go through several stages of growth. At each stage, the nymphs shed their exoskeletons, a process called molting. The nymphs start out small, as you can see from the photo below, and look quite different from adults.

Adults can grow up to 6 cm long and are creamy-white with a marbled green pattern. And, of course, they have wings!

They have a small pointed shield on their backs and the inside of their forelegs are orange and blue with white spots. Females have thin antennae (above) and males have feathered antennae (below).

To notice these while wandering through wadis, you’ll have to stop and take a closer look at the plants. I have spotted these mantises on a variety of desert plants – capers, acacias, and nimnam – but most often I find them on dhafrah plants (Iphiona scabra), pictured below.

Egyptian Flower Mantises are experts at camouflage and wait patiently on the plant for prey to pass by. Their arms are well-designed to catch flying insects. In fact, what usually draws my attention is the sight of a butterfly, still and unmoving, on the bush. An odd sight as butterflies are usually flitting around quite a bit. On closer inspection, I’ll find the butterfly is not moving because it has become breakfast for either a mantis or a spider!

I’ve seen these mantises in several of the wadis around Dahab and also higher up in the area around St. Katherine’s. Where have you spotted them?