This article is about the insect

Insect

Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...

 anatomical structure. For the plant genus Cenchrus see Sandbur

Sandbur

Cenchrus is a genus of about 25 species of grasses in the family Poaceae. Common names include buffelgrasses, sandburs, and sand spur. Some botanists include the genus within the related genus Pennisetum.-Species:...

The cenchrus (plural cenchri) is a specialized anatomical structure in the insect

Insect

Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...

 group known as sawflies

Sawfly

Sawfly is the common name for insects belonging to suborder Symphyta of the order Hymenoptera. Sawflies are distinguishable from most other Hymenoptera by the broad connection between the abdomen and the thorax, and by their caterpillar-like larvae...

. The cenchri are small blister-like lobes on the metanotum of these insects, just posterior to the mesothoracic

Mesothorax

The mesothorax is the middle of the three segments in the thorax of an insect, and bears the second pair of legs. Its principal sclerites are the mesonotum , the mesosternum , and the mesopleuron on each side...

 scutellum, shaped and positioned in such a way as to latch onto the base of the front wings

Insect wing

Insects are the only group of invertebrates known to have evolved flight. Insects possess some remarkable flight characteristics and abilities, still far superior to attempts by humans to replicate their capabilities. Even our understanding of the aerodynamics of flexible, flapping wings and how...

when they are folded at rest. There are corresponding small patches on the wings where the membrane is roughened, to increase the friction against the dorsal surface of the cenchri. This is a unique mechanism among the insects.