Reductive tendences on the synflorescences of the southern Calceolaria species. Patterns similar to these and new ones are reported in the present paper, as revealed by a study of 35 species from southern South America. According to this study, the basic synflorescence type is found in section Rugosae . Other morphological and caryological data support the view of this section as more ancestral in the southern range of the genus. Extreme reduction in these groups lead to single flowered inflorescences.
Truncation is an other kind of reduction pattern and is found in other groups as isolated events.
Different strategies of flower exposition are evident mainly in the rosulate species depending on which part of the synflorescences suffers elongation. Facultad de Ciencias Exactas F sicas y Naturales, Univ.