9. Croton didrichsenii Webster (1992: 271) .

— Julocroton humilis Didrichsen (1857: 132) .

Type:— BRAZIL. São Paulo: “campis Mugi ”, November 1833, P.W. Lund s.n. (holotype C 10011298 !; isotypes A 00277247!, C 10011297!, G 00312779!). (Fig. 5, G–I)

This subshrub can be recognized by its densely yellowish to ferrugineous indumentum, the presence of a xylopodium, congested inflorescences, and pinnatifid pistillate sepal. It shares several morphological characters with C. triqueter . However, C. didrichsenii is a subshrub found in ‘cerrado’, while C. triqueter is a shrub found mainly at the edge of forests. The species belongs to Croton sect. Julocroton (van Ee et al. 2011) .

Distribution and habitat:— It ocurrs in Argentina, Bolivia, Brazil (BA, DF, GO, MG, MS, MT, PR, RS, SC, SP, TO), Paraguay, and Uruguay (Caruzo & Cordeiro 2007, Cordeiro 1990, Caruzo et al. 2020). It is frequently found in open vegetation (‘campo limpo’ and ‘cerrado’), between 550 and 1050 m elevation. (Fig. 6).

Phenology:— Flowering and fruiting from September to March.

Representative specimens:— PARANÁ: Campo Mourão, Cerrado Valtra, 24°00’’52.04’ S, 52°21’47.02”W, 555 m, 18 October 2016, A. P. N . Pereira, F. S . Petrongari & O. L. M . Silva 30 (SP). Jaguariaíva, Parque Estadual do Cerrado, 05 November 1994, A . Uhlmann 94 (MBM, UPCB). Idem, Lageado 5 Reis, 18 September 1975, G . Hatschbach 37085 (MBM). Piraí do Sul, Rodovia PR-090, 10 km O do alto da Serra das Furnas, 12 January 2000, G . Hatschbach, M . Hatschbach & J. M . Silva 69899 (MBM). Tibagi, Fazenda Monte Alegre, 16 September 1952, G . Hatschbach 3078 (MBM) .