BALDUINIA

O gênero Heterothalamus Lessing e táxones afins

Abstract: The genus Heterothalamus Lessing and genera allied are studied, as a contribution to the knowledge of south-american flora, especially from Brazil, Argentina and Uruguay. The genus Heterothalamulopsis is a taxonomic novelty. Heterothalamulopsis wagenitzii, single species of the genus until this moment, is a dioecious small glandulous and ramified shrubs, provided with persistent bristled and broad apex pappus in male flowers, and with ligulate female flowers, protected by persistent paleas. The species, endemic of southern Brazil, occurs only on the border of the “Aparados da Serra Geral”, in the states of Rio Grande do Sul and Santa Catarina. The genus Heterothalamus comprises three polygamo-dioecious or imperfect-dioecious species of small glandulous and ramified shrubs, characterized by the presence of 1-2-series of radial, female or neutral flowers, in functional male heads, and by the presence of ligulate flowers, protected with persistent paleas, in female heads. The geographic distribution of the genus includes central Argentina (provinces of Cordoba, San Luis, La Rioja and Santiago del Estero), Uruguay and southern Brazil (states of Rio Grande do Sul and Santa Catarina). It is supplied a key to set apart the genera of subtribe Baccharinae Lessing, found in the brazilian, argentinian and uruguayan floras. Another key is furnished to distinguish the three studied species of Heterothalamus. Baccharis czermackii Hochreutiner was presently reduced to the synonymity of Heterothalamus psiadioides Less. Key words: Heterothalamus, Heterothalamulopsis, Baccharineae, Astereae, Asteraceae.

Notas sobre a ocorrência de Celtis pallida Torrey ssp. Pallida (Ulmaceae) na flora sul-rio-grandense

Abstract: The occurrence of Celtis pallida ssp. pallida is confirmed in the state of Rio Grande do Sul, Brazil. Taxonomic considerations, a botanical description and a kew for the identification of the species are also furnished. Key words: Celtis pallida Torrey ssp. pallida, Ulmaceae, Celtidaceae, Rio Grande do Sul.