1) Fungus genus 2) Genus claviceps 
(from the article `Ascomycota`) ...insects. It forms a small, 3–4-centimetre (about 1 13-inch) mushroomlike fruiting structure with a bright orange head, or cap. A related genus, ...
A genus of ascomycetous fungi, family clavicipitaceae, order clavicipitales, parasitic on various grasses; the sclerotia contain several toxic alkaloids. Claviceps purpurea on rye causes ergotism. ... (12 Dec 1998) ... 
(klav´ĭ-seps) a genus of parasitic fungi that infest various seed plants. C. purpu´rea is the source of ergot.
[n] - fungi parasitic upon the ovaries of various grasses
genus Claviceps noun fungi parasitic upon the ovaries of various grasses