Thismia singeri (de la Sota) Maas et al. (1986: 166)

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 : 270-272

4. Thismia singeri (de la Sota) Maas et al. (1986: 166) .

≡ Mamorea singeri de la Sota (1960: 45) . ( Fig. 7 )

Herb 6,5–7 cm tall. Roots 5–5,7 × 0,1 cm, not tuberous, filiform, white-brownish. Tuber absent. Stem 4,8–6 × 0,1–0,3 cm, white. Leaves 7, 3–7 × 1,5–3 mm, reduced, alternate, narrowly-triangular to lanceolate, base truncate to cuneate, apex acute, white-hyaline. Flower 1,9–2,2 × 1,7–2,7 cm, pedicellate; pedicel 8 × 3 mm, white; ovary 4 × 5 mm, wide-obovoid, 3-angular, white-brownish; flower tube 1,4–1,6 × 0,9–1,1 cm, ellipsoid, internal surface horizontally striated, brown; tepals in two different whorls (3+3); outer tepals 3, 13–17 × 8–10 mm, inserted in the 1/3 basal of the tube, sub elliptical, laminar, base decurrent, margin entire, apex rounded, brown; inner tepals ca. 7 × 5 mm, curved over the annulus, unguiculate, blade subrounded, sub ovoid, obovoid or sub spatulate, base rounded, apex rounded to inconspicuously obtuse, brown; annulus ca. 2 mm length, hexagonal. Anther 1,5 × 1,5 mm, obovate; filament ca. 1 mm length, filiform. Stigma ca. 3 × 3 mm, general form sub pyramidal, white to brownish; lobes descendant with apex strongly curved to the center. Fruit ca. 6 × 7 mm, pale brown; pedicel ca. 9 × 2 mm, estiolated, whitish.

Specimens examined: — BRAZIL. Mato Grosso: Alta Floresta, RPPN Cristalino, Taboca trail, Ombrophilous Dense Forest , near to Cristalino river , 25 January 2016, fl., fr., D. F. Silva & L. L. Mota 01 ( HERBAM) ; RPPN Cristalino, Taboca trail, Ombrophilous Dense Forest, near to Cristalino river , 25 January 2016, fl., D. F. Silva & L. L. Mota 02 ( HERBAM) ; RPPN Cristalino, Taboca trail, Ombrophilous Dense Forest, near to Cristalino river , 27 December 2016, fl., D. F. Silva & S. Sourell 22 ( HERBAM) ; RPPN Cristalino, Taboca trail, Ombrophilous Dense Forest, near to Cristalino river , 27 December 2016, fl., fr., D. F. Silva & S. Sourell 23 ( HERBAM) ; RPPN Cristalino, Taboca trail, Ombrophilous Dense Forest , 5 January 2018, fl., R. S. Ribeiro 345 ( HERBAM) .

Geographic distribution: — Bolivia, Ecuador, and Brazil ( Voloschen et al. 2013). This species was reported recently for Brazil in the Pará State, by Voloschen et al. (2013), corresponding to the second collection in Brazil and fourth of the species. It is the first register of geographic distribution in the Brazilian Central-West Region, in the Mato Grosso State.

Discussion: —It may be recognized among other species of the study area by the absence of tuberous stem; filiform roots (<1 mm thickness); alternate leaves; tepals in two heights, the inner tepals free (mitre absent); anthers obovate; stigma with descendant lobes. Found flowering and fruiting between December and January. The drawline of this species can be found in Voloschen et al. (2013).

Figures

FIGURE 7.—Thismia singeri—A–B. Flowering habit. C. Detail of the flower button. D. Flower in dorsal-lateral view. E. Dorsal view of the flower with outer tepals distended, showing annulus. F. Flower sectioned, showing internal cavity, anthers, stigma and ovary. G. Side view of the fruit. H. Frontal view of the fruit. Photographs: A, C and F–G. Susanne Sourell; B, D and G–H. Luísa Lima e Mota.