Cyathea delgadii Pohl ex Sternb.

4.1. Cyathea delgadii Pohl ex Sternb., Vers. Fl. Vorwelt 1: 47. 1820. Plants terrestrial. Stem erect, arborescent. Fronds 140–215.2 cm long, monomorphic, 2-pinnate-pinnatifid, pendent; petiole 52–92 cm long, brown to blackish brown, adaxially sulcate, with prickles and lanceolate scales at the base, scales 0.9–1.7 cm long, shiny, pale brown, concolorous, rarely with the central portion near the base slightly blackish; rachis adaxially sulcate, with short prickles on the proximal portion, and dense hairs adaxially, sparse abaxially; laminae 69.5–137 × 10–14.6 cm, oblong, gradually narrowed distally; pinnae ca. 55 × 17 cm, 17–21 pairs, pinnules 6.5–8.5 × 1.3–2 cm, pinnatifid, chartaceous, abaxially with sparse and short hairs, and scales at the base of the costae, margins crenate to serrate, pinnatifid apex; veins forked. Sori rounded, medial to supramedial; indusia sphaeropteroid, globose. Examinedmaterial: MARANHÃO: Alto ParnaÍba, PNNRP, Cachoeira do Sussuapara, 10°09’56’’S, 45°55’38’’W, 380 m, 21.IV.2022, P. H.C. Aguiar et al. 38 (CCAA); P. H.C. Aguiar et al. 39 (CCAA); P. H. Castro-Aguiar et al. 163 (CCAA); P. H. Castro-Aguiar et al. 164 (CCAA); Fazenda do Merval, próxima a casa de serraria, 09°49’22’’S, 46°16’14’’W, 373 m, 19.VII.2023, P. H. Castro-Aguiar et al. 319 (CCAA, UB). PIAUÍ: Barreiras do PiauÍ, PNNRP, Cachoeira do Urubu, 10°11’45’’S, 45°47’48’’W, 470 m, 14.XII.2022, P. H. Castro-Aguiar et al. 107 (CCAA). Cyathea delgadii has a Neotropical distribution, occurring from Costa Rica to Paraguay (Lehnert 2011; Weigand & Lehnert 2016). In Brazil, it is recorded for all biomes (Pietrobom et al. 2023). In the study area, it was observed exposed to the sun, close to waterfalls, and in shaded areas on the banks of streams, inside the gallery forest. Cyathea delgadii is characterized by having concolorous scales, shiny petiole, laminae abaxially with scarce and minute hairs on the veins, glabrous adaxially, and spheropteroid, globose indusia.