In 1944, Hyde and Williams coined the term palynology to name the science responsible for the study of pollen grains and fungal spores. It was from the middle of the twentieth century onwards that the study of these particles progressed considerably, thanks to the appearance of electron microscope (Knoll and Ruska 1932) which improved the resolution and magnifcation reached with the optical microscope at the beginning of the seventeenth century. Size or type, number or position of apertures or even sporoderm ornamentation of pollen grains and fungal spores can be used as taxonomic characters for the identifcation, differentiation and classifcation of plant species or fungi they are coming from. For that reason, the study of pollen grains and fungal spores has its application in disciplines apparently as disparate as vegetal taxonomy, paleopalynology (study of palynomorphs present in different sediments for paleoclimatic and paleoecological reconstructions), aeropalynology (airborne pollen and fungal spores content), medicine (related to allergies) or even in forensic palynology, agronomy (control of crop pollination or phytopathogen detection, among others), biodeterioration, etc. and of course, the subject that concerns us in this book, melissopalynology (study of pollen content and fungal spores in honeys and other hive products). In honey, pollen grains come mainly from the plant species foraged by honey bees (Ohe et al. 2004), so that palynological studies provide a good fngerprint of the plant species where the honeys come from (botanical origin) .