Caseolus subcalliferus is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Geometridae, the hairy snails and their allies.
This species is endemic to Porto Santo, Portugal.
It lives on upper parts of various plants including Juncus maritimus.
The survival of this species is threatened by habitat loss, mainly from land-use management or fire, but also habitat degradation due to introduction of invasive plants.