Six hypogeous fungi of Ascomycotina and Basidiomycotina have been studied from semiarid zones in Southern Spain. Melanogaster variegatus (Vitt.) Tul. is recorded for the first time from Spain. Picoa juniperi Vitt. and Terfezia claveryi Chat. are revealed as the most frequent species in semi-arid zones. Taxonomical problems on Tuber puberulum Berk. & Br. are discussed; Geopora arenicola (Lév.) Kers and G. cooperi Hark. are also commented on.