Neochlamisus

thumb|Larval fecal case thumb|Larva removed from its fecal case

Neochlamisus is a genus of leaf beetles in the tribe Fulcidacini (the warty leaf beetles). They are members of the case-bearing leaf beetle group, the Camptosomata. Measuring 3–4 millimeters in length as adults, they are cryptic, superficially resembling caterpillar frass. Seventeen, sometimes 18 species are presently accepted in this genus, all of them occurring in North America (including Mexico; some were previously in the genus Chlamisus).