The genus Haematomma is treated as part of the Ticolichen biodiversity inventory in Costa Rica. Together with literature reports, fourteen taxa are recognized as occurring in the country (plus three species to be expected), and three of them are new to science: Haematomma nicoyense Nelsen, Lücking & Chaves, with a sorediate thallus, russulone and atranorin, and zeorine apothecia with a split between proper excipulum and thalline margin, Haematomma staigeriae Nelsen, Lücking & Umaña, with a sorediate thallus, russulone and lichexanthone, and submuriform ascospores, and Haematomma fluorescens var. longisporum Nelsen, Lücking & Navarro, with russulone and lichexanthone and ascospores up to 120 μ m in length with up to 27 septa. A key is presented for the 17 taxa known or expected from Costa Rica.
