14. Astrocaryum arenarium Barbosa Rodrigues (1898: 53) .

Type:— BRAZIL. Prov. Mato Grosso [Mato Grosso state]: Serra da Chapada, s.d., Barbosa Rodrigues 214 (probably destroyed) . Lectotype [designated by Glassman (1972: 15) as “type”, here corrected]:—Illustration in Barbosa Rodrigues (1898: Tab. XVIII) .

Notes:—The taxonomic identity of this species remains uncertain. Despite A. arenarium being considered valid according to POWO (2024), it is often categorized as dubious or potentially extinct (Lorenzi et al. 2010).About the type, as with all other previously reported species, the specimen indicated in the protologue of Astocaryum arenarium was probably destroyed. Based on substantial historical information, the material was deposited in the personal collection of Barbosa Rodrigues, which was subsequently lost during a bad flood in the city of Rio de Janeiro (Glassman 1972, Stafleu & Cowan 1976, Batista et al. 2011, Buzatto et al. 2011, Rodrigues 2012, Stauffer et al. 2016). Consequently, the only remaining original material is an illustration (Fig. 11) of the species in the protologue ( Barbosa Rodrigues 1898), which Glassman designated as the type. Here, we recognize this illustration as a lectotype, following the guidelines outlined by Turland et al. (2018).