Guaiacum sloanei Shuttlew. Dataset GBIF Backbone Taxonomy Rank SPECIES Classification kingdom Plantae phylum Tracheophyta class Magnoliopsida order Zygophyllales family Zygophyllaceae genus Guaiacum species Guaiacum sanctum Name Homonyms Guaiacum sloanei Shuttlew. ex A.Gray Guaiacum sloanei Shuttlew.