Scute

The term is also used to describe the anterior portion of the mesothorax in insects as well as some arachnids (e.g., the family Ixodidae, the scale ticks).

Forming in the living dermis, the scutes produce a horny outer layer that is superficially similar to that of scales.

Prehistoric ancestors of mammals, the synapsids, are thought to have scutes which were later reduced and replaced by hair.

Some fish, such as pineconefish, are completely or partially covered in large armored scales commonly termed scutes.

[9][10] The term "scutum" is also used in insect anatomy, as an alternative name for the anterior portion of the mesonotum (and, technically, the metanotum, though rarely applied in that context).

In the hard ticks, the Ixodidae, the scutum is a rigid, sclerotised plate on the anterior dorsal surface, just posterior to the head.

Males do not engorge nearly as drastically as females, so they do not need a flexible alloscutum; instead the rigid scutum covers practically the entire dorsal surface posterior to the head, and may be referred to specifically as the conscutum.

Scutes on an alligator foot
Scute of the carapace of a Texas tortoise
This detail of a Glyptodon displays its scutes. From the collection of the Children's Museum of Indianapolis .
The pineconefish
Conspicuous scutum on a typical female hard tick before she has fed. Note the pale eye-spots near the edges of the scutum, roughly between the 2nd and 3rd legs
The same scutum is relatively less conspicuous after the tick has fed, because it has not changed in size, whereas the tick has swollen as it engorged
In the typical male hard tick, the conscutum covers practically the whole back