Thismia hyalina (Miers) Bentham & Hooker ex Mueller (1891: 234)

Silva, Diego Ferreira Da, Engels, Mathias Erich & Soares-Lopes, Célia Regina Araújo, 2020, Novelties in Thismia (Thismiaceae) from South Brazilian Amazon with the description of a new species, Phytotaxa 429 (4), pp. 261-273 : 263

1. Thismia hyalina (Miers) Bentham & Hooker ex Mueller (1891: 234) .

≡ Myostoma hyalinum Miers (1866: 474) . ( Fig. 1–2 )

Herb 2.5–7.5 cm tall. Roots 0.5– 5 cm length, not tuberous, filiform, white-hyaline. Tuber 3–10 × 3–6 mm, irregular, laterally flattened, pale brown. Stem 1–4.6 × ca. 0. 1 cm, white. Leaves 3–4, 3–6 × 1.5– 2 mm, reduced, verticillated right below the flower, narrowly-triangular to deltoid, base truncate, margin entire, apex acute, white-hyaline. Flower 1,1–1,6 × 1–2 cm, pedicellate; pedicel 1–3 × 1 mm, white-orange; ovary 2–3 × 3–4 mm, wide-oval to subrounded, 6- angular, pale orange to dark red; flower tube 1,1 × 0,6–0,8 cm, obovoid, 6–angular, internal surface smooth, dark red with macules white-metallic; tepals in two distinct whorls (3+3), outer tepals 11–12 mm length, filiform, cylindrical to subcylindrical, base truncate, apex rounded; inner tepals ca. 6 × 5 mm, curved over the annulus, obovate, base rounded, giving the impression of subcordate in natural position, apex rounded, red dark with whitish margin; annulus ca. 2 mm length, rounded. Anther 5 × 5 mm, rounded, auriculate at base; style ca. 5 mm length, filiform. Stigma ca. 4 × 1,5 mm, general form elliptical , orange; lobes ascendants with apex slightly curved to the center. Fruit ca. 10 × 8 mm, whitish-hyaline with the carpels union orange; pedicel ca. 5 × 0.1–0.2 cm, estiolated, whitish.

Specimens examined: — BRAZIL. Mato Grosso: Alta Floresta: RPPN Cristalino, Taboca trail, Alluvial Ombrophilous Dense Forest , near to Cristalino river , 28 January 2016, fl., fr., D. F. Silva & L. L. Mota 05 ( HERBAM) ; RPPN Cristalino, Taboca trail, Alluvial Ombrophilous Dense Forest, near to Cristalino river , 28 January 2016, fl., fr., D. F. Silva & L. L. Mota 06 ( HERBAM) ; RPPN Cristalino, Taboca trail, 5 January 2018, fl., fr., R. S. Ribeiro 346 ( HERBAM) ; Estância Jardim farm, 12 March 2018, fl., D. F. Silva & R. S. Ribeiro 44 ( HERBAM) ; Estância Jardim farm, 12 March 2018, fl., fr., D. F. Silva & R. S. Ribeiro 45 ( HERBAM) ; fragment of Alluvial Ombrophilous Dense Forest, near to Teles Pires River, 17 March 2018, fl., fr., D. F. Silva & R. S. Ribeiro 50 ( HERBAM) ; Fragment ofAlluvial Ombrophilous Dense Forest, near to Teles Pires River , 17 March 2018, fl., D. F. Silva & R. S. Ribeiro 51 ( HERBAM) ; Novo Mundo: RPPN Cristalino, Cacao trail, 26 December 2016, fl., fr., D. F. Silva & S. Sourell 20 ( HERBAM) ; RPPN Cristalino, Cacao trail, 26 December 2016, fl., fr., D. F. Silva & S. Sourell 21 ( HERBAM) RPPN Cristalino, Castanheira trail, 26 December 2016, fl., fr., D. F. Silva & S. Sourell 43 ( HERBAM) .

Geographic distribution: —Occurs in Peru and Brazil ( Govaerts 2019). In Brazil the species occurs in the North Region (Acre and Amazonas) and in the Southeast Region (Rio de Janeiro and São Paulo) ( Flora do Brasil 2020 em contrução 2019), being the first record of geographic distribution for the Central-West Region, in the Mato Grosso State.

Discussion: —This species may be differentiated from the other species of Thismia that occur in the study area by its tuberous stem; verticillate leaves in the apex of the stem, and juxtaposing to the flower; outer tepals cylindrical and filiform; inner tepals free between each other; anthers with connective not dilated; stigma with ascending lobes. Found flowering and fruiting between December and March.

Figures

FIGURE 1.—Thismia hyalina—A. Flowering habit. B. Fruiting habit. C. Leaf. D. Inner tepal distended. E. Inner tepal in natural position. F. Anther. G. Stigma. H. Frontal view of fruit.A, C–G based on D.F. Silva 05; B and H based on D.F. Silva 20. Drawing by M.E. Engels.

FIGURE 2.—Thismia hyalina—A–B. Flowering habit. C. Side view of the flower. D. Dorsal view of the flower. E. Flower after falling of the perianth. F. Flower after falling of the perianth, showing stigma. G–H. Fruit. Photographs: A, E–H. Susanne Sourell; B–D. Luísa Lima e Mota.