Two new Brazilian species of Tachia (Gentianaceae: Helieae)

Abstract

SUMMARYTwo new species of Tachia (Gentianaceae: Helieae) are described from Brazil. They share the un usual characteristic of quadrangular, winged stems, formerly only known from Tachia longipes in Suriname. They differ from this species in their larger, winged, keeled, and long acuminate calyx lobes. Tachia lancisepala, spec. nov., is only known from one collection from the State of Rondônia in Brazil, and has unusually large and broadly funnelshaped corollas and ovate leaves with winged petioles. Tachia siwertii, spec. nov., has been found in three separate areas in southern Amazonas and Pará (Brazil) and is characterized by more elliptic leaves, unwinged petioles, and a narrower corolla than T. lancisepala. RESUMODuas novas espécies de Tachia (Gentianaceae: Helieae) oriundas do Brasil são descritas. Ambas compartilham os ramos quadrangulares e alados, características observadas originalmente apenas em Tachia longipes do Suriname. Diferem dessa espécie em seus lobos do cálice maiores, alados e longamente acuminados. Tachia lancisepala, spec. nov., é conhecida somente de uma coleção do estado de Rondônia no Brasil e tem corolas particularmente grandes e amplamente infundibuliformes e folhas ovadas. Tachia siwertii, spec. nov., tem sido encontrada em três diferentes áreas ao sul do Amazonas e Pará (Brasil), sendo caracterizada por folhas mais elípticas, pecíolos não alados e pela corola mais estreita do que de T. lancisepala.

Revision of <I>Tachia</I> (Gentianaceae: Helieae)

“…The last comprehensive monograph of the genus was published by , also authors of Flora of the Guayana Highlands, and they described six new species in their revision. Since then, three additional species have been described and many new collections have been accumulated (Cobb and Maas 1998;Struwe et al 2005).…”

In vitro and in vivo antimalarial activity and cytotoxicity of extracts, fractions and a substance isolated from the Amazonian plant Tachia grandiflora (Gentianaceae)

“…The structures of these substances were not defined. Based on the diagnostic morphological characters of the drawing of caferana in Pio Correa’s book, the species was either Tachia lancisepala or Tachia siwertii , both scientifically described only in 2005 (Struwe et al 2005). …”