25. Croton myrianthus Müller Argoviensis (1865: 138) .

Type: — BRAZIL. ‘in Brasilia Meridionali’, s.d., F. Sellow 3936 (holotype B† ; lectotype SP 18550! designated by Lima & Pirani 2008b; isolectotypes A 00257962!, photo F 0 BN005137!, G 00434607!, NY 00262931!) (Fig. 15, A–B).

Croton myrianthus is a shrub with subentire lepidote trichomes on both leaf surfaces, and unisexual inflorescences. Lima & Pirani (2008b) pointed out the similarities between C. myrianthus and C. uruguayensis, however, the two species can be distinguished by inflorescence size (up to 2 cm long in C. myrianthus vs. up to 7 cm in C. uruguayensis), and by leaf shape (elliptical, ovate or ovate-lanceolate in C. myrianthus vs. narrowly elliptic to narrowly lanceolate in C. uruguayensis). The species belongs to section Lamprocroton subsect. Lamprocroton (van Ee & Berry 2011) .

Distribution and habitat:— It occurs in southern (PR, RS, SC) Brazil (Caruzo et al. 2020), where it grows in open vegetation, frequently close to riverbanks, between 700 and 990 m of elevation (Fig. 14).

Phenology:— Flowering and fruiting from October to March.

Representative specimens:— PARANÁ: Bituruna, Fazenda Lageado Grande, 987 m, 18 September 2004, D. Liebsch 798 (UPCB). Dois Vizinhos, Foz do Chopim, 9 December 1968, G . Hatschbach 20578 (MBM, NY, RFA, UPCB). General Carneiro, Fazenda São Pedro, Lagoa Sanguessuga, 01 October 2004, A. C . Cervi 8678 (UPCB). Guarapuava, Rio Coitinho, 15 December 1965, R . Reitz & R. M . Klein 17657 (NY, P). Palmas, 04 November 1998, A . Soares & W . Maschio 282 (HFC, HUEM) .