In this paper, we introduce the Le ́xico de Formas Flexionadas del Español (Leffe), a wide-coverage morphological and syntactic Spanish lexicon based on the Alexina lexical framework. We explain how the Leffe has been created by merging together several heterogeneous lexicons and how the Alexina lexical framework has been applied to Spanish. We also introduce a semi-automatic technique based on a tagger to detect the lexicon's deficiencies. A preliminary evaluation shows the potential of the Leffe and the relevance of both creation and extension processes.