Hamadas

Fazzan: reg and dhayas, the Messak

The harshest environment, beaten by the wind, burnt by the sun and sometimes freezing in winter is the Messak Plateau. It is the tilted structural surface of the Nubian Sandstones (Early Cretaceous) plunging with a 2° dip from the escarpment overlooking the Tayta Gravel Plain to the West to vanish beneath the sand of the Edeyen Murzuq to the East. Elevations range between 800 and 1100 m. It is incised by wadis and canyons preserving fragile relict habitats.

Its surface is a barren plateau covered by gravel to boulders, which correspond to a deflated soil of the Neolithic humid periods. Locally muddy depressions, rarely filled with water, can preserve some life even in the driest periods, like Tenebrionids under stone, some wood borers and other insects associated with rare small Acacia.

Beetles: Mesostena angustata (Fabricius, 1775); Trachyderma hispida (Forskal, 1775); Pimelia canescens interstitialis Solier, 1836; various Buprestids and Cerambycids in Acacia branches (not collected there).

Main plants: Anastatica hierochuntica (Brassicaceae); Acacia tortilis (Papilionaceae); Atractylis sp. (Asteraceae); Anvillea garcini...

	*Fazzan: reg and dhayas, the Messak* The harshest environment, beaten by the wind, burnt by the sun and sometimes freezing in winter is the Messak Plateau. It is the tilted structural surface of the Nubian Sandstones (Early Cretaceous) plunging with a 2° dip from the escarpment overlooking the Tayta Gravel Plain to the West to vanish beneath the sand of the Edeyen Murzuq to the East. Elevations range between 800 and 1100 m. It is incised by wadis and canyons preserving fragile relict habitats. Its surface is a barren plateau covered by gravel to boulders, which correspond to a deflated soil of the Neolithic humid periods. Locally muddy depressions, rarely filled with water, can preserve some life even in the driest periods, like Tenebrionids under stone, some wood borers and other insects associated with rare small Acacia. Beetles: Mesostena angustata (Fabricius, 1775); Trachyderma hispida (Forskal, 1775); Pimelia canescens interstitialis Solier, 1836; various Buprestids and Cerambycids in Acacia branches (not collected there). Main plants: Anastatica hierochuntica (Brassicaceae); Acacia tortilis (Papilionaceae); Atractylis sp. (Asteraceae); Anvillea garcini...

	The Messak Plateau (reg) with a muddy dhaya in the background: upper Imrawen


	A Dhaya with a small Acacia tortilis near Wadi Tilizaghen


	A dry rose of Jericho (Anastatica hierochuntica, Brassicaceae) in a Dhaya near wadi Ti-n-Hamutin.