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| Thismia pseudomelanomitra in Silva, Ribeiro et Braga, 2023. |
Abstract
A new species of Thismia is described and illustrated for the Brazilian Amazon Forest. Thismia pseudomelanomitra belongs to Thismia subg. Ophiomeris sect. Pyramidalis and is morphologically similar to T. melanomitra. However, it can be recognized by its orbicular outer tepals with revolute margins, inner tepals connate over the tube opening forming a subglobose mitre, outer surface bearing prominent irregularly dentate ribs and irregularly foveae on top. The new species is known from a single locality, collected at São Nicolau Farm, in the northwest of Mato Grosso State. Herein, we provide a detailed description with illustrations, photographic plates, distribution maps, and preliminary conservation status.
Keywords: Dioscoreales, Flora of Brazil, neotropics, taxonomy, Monocots
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| Thismia pseudomelanomitra.
A. Flowering habit. B–C. Leaves. D. Top view of the flower, showing the arrangement of the tepals and foveate mitre. E. Longitudinal section of floral tube with outer and inner tepals, stamens, stigma, placentation and inner surface with striated laminar projections. F. Outer tepals. G. Flower in side view, showing the details of the inner tepals. H. Detail of the stamens, stigma, placentation and inner surface of the floral tube. I. Detail of the inner surface of mitre, colliculate. J. Detail of the inner surface of floral tube with striated laminar projections.
Drawing by Marcus Falcão |
Thismia pseudomelanomitra
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| Thismia pseudomelanomitra.
A. Panoramic view of the area habited by T. pseudomelanomitra.
B–F and H. Flowering habit (in situ). G and I. Detail of the mitre, showing the variation in the number of foveae.
Photographs by Diego Ferreira da Silva. |
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| Thismia pseudomelanomitra.
A. Flowering habit. B. Leaves. C. Outer tepals. D. Mitre upper view. E. Detail of the outer surface of floral tube, showing the longitudinally arranged irregularly sized verrucae. F. Longitudinal section of floral tube with outer and inner tepals, stamens, stigma, placentation, and inner surface with striated laminar projections. G. Detail of the inner surface of mitre, colliculate. H. Detail of the annulus. I. Detail of the annulus surface. J. Stamen. K. Stigma and placentation.
Photos are provenient of the material in alcohol, disregard coloration. Photographs by Diego Ferreira da Silva. |
Diego Ferreira da Silva, Ricardo Da Silva Ribeiro and João Marcelo Alvarenga Braga. 2023. Thismia pseudomelanomitra (Thismiaceae), A New mycoheterotrophic Species from Brazilian Amazon Forest. Phytotaxa. 597(2); 175-183. DOI: 10.11646/phytotaxa.597.2.7