[4] Although it is distinctively coloured, the sedentary behaviour of C. tubularis allows epibionts to colonise its shells, providing excellent camouflage, and it can easily go unnoticed; it was first reported on the coast of the Portuguese mainland in 2011, but is thought to have been living there for a long time.

[7][8] Males inhabit gastropod shells, chiefly those of Pisania maculosa or Cerithium vulgatum,[5] which they can move freely; females occupy the fixed tubes made by the vermetid snail Lementina arenaria.

[1] It was later described by Polydore Roux as Pagurus ornatus, and that species was transferred to the genus Calcinus in 1892 by Édouard Chevreux and Eugène Louis Bouvier.

[1] Lipke Holthuis recognised that C. ornatus was a junior synonym of Cancer tubularis, and transferred Linnaeus' species to the genus Calcinus, at which point it reached its current scientific name.

[7] Linnaeus' description is imprecise, and could refer to "practically any hermit crab",[10] but the type locality (the Mediterranean Sea), together with the statement that it lives in worm tubes, restricts the possibilities to this one species.