The genus was named by Ralph Vary Chamberlin in 1918, after Professor William A. Hilton of Pomona College who collected the type specimen of H.

The legs are short, usually not reaching the sides of the body when held horizontally.

Like many other spirobolids, color ranges from brown to nearly black, and thin bands of red or yellow may occur on the rear margins of each segment.

[2] The northernmost species are H. pulchrus and H. carpinus, ranging into southern California and northern Arizona, respectively.

Tylobolus species can be distinguished by larger maximum size (up to 92 mm or 3.6 in long), having more ocelli per eye patch (27–50), a larger hooked process on the coxa of the third leg in males, and in details of the gonopods, male reproductive structures.