Fig. 1. In vitro development of joint fungal and algal cultures. (A) Phaeococcomyces chersonesii (A49) while co-cultured with Asterochloris (AB99.109B3) develop extensive contact zones, no growth inhibition of either partner is observed. (B) Colony of a Coniosporium-like strain A10 growing on a cellophane support between two colonies of Trebouxia AB99.051C5. (C) Coniosporium apollinii and T. asymmetrica; algal colony on the left side is partially exchanged for an intermixed culture of both partners. (D) After more prolonged periods of cultivation (over 80 d) some algal colonies were loosing pigmentation (Coniosporium apollinii A28 co-cultured with Trebouxia AB99.046B4). (E) The rock inhabiting strain AN11 and Asterochloris form an intermixed borderline between the streaked out colonies. The pattern of growth shows a balanced relation with no particular dominance of any partner. (F) After a week of co-cultivation Aspergillus niger overgrows two developed Trebouxia colonies (compact growth zones) on a cellophane support.