Phylum: Basidiomycota Family: Pucciniaceae
Gymnosporangium clavariiforme (Wulfen) de Candolle, 1805
Tongues of Fire
An uncommon rust fungus with two hosts. The aecial stage in the autumn can be found on various species of Rosaceae with the most common being hawthorn (Crataegus laevigata). The telial stage appears in spring, on juniper, as orange horn-type structures, most obvious in wet weather when they swell
References:
Ellis & Ellis (1997) - Microfungi on Land Plants;
Termorshuizen & Swertz (2011) - Dutch Rust Fungi;
Wilson & Henderson (2011 reprint) - British Rust Fungi