The surface mycoflora of "chorizo de Cantimpalos", a Spanish variety of fermented meat sausage characterised by a natural white covering, has been investigated. Among 54 mould strains isolated, 38 belonged to Penicillium subgenus Penicillium. The major species found (18 isolates) was identified as Penicillium commune, and the other dominant species (13 isolates) was identified as P. olsonii. None of the P. olsonii isolates produced cyclopiazonic acid, mycophenolic acid, roquefortine C. patulin or ochratoxin A, but all P. commune isolates produced cyclopiazonic acid. Toxicity to Artemia salina larvae was very high for all P. commune isolates investigated, while no isolates of P. olsonii studied were toxic to these crustaceans. The results may assist in selection of nontoxic strains, which could be used as surface starters in the manufacture of this type of sausage. The apparent inability to produce penicillin is a valuable characteristic to take into account in the selection process.