5. Meriania callosa Rob.Fern., R.Goldenb.& Michelang., Willdenowia52(1): 49 (2022).

Type:— PERU. Amazonas: Prov. Bongará, Dist. Yambrasbamba, ruta desde CP Santa Rosa hacia bosque El Toro, 1950 m, 05°40’07.98”S, 77°55’30.04”W, 11 Nov 2020 (fl.), R. Fernandez-Hilario, W. Chuquitucto & A. Wong 2055 (holotype: MOLF! [barcode 000007]; isotypes: HOXA! [accession no. 077833], KUELAP! [accession no. 971], MOLF! [barcode 000008], NY! [barcode 04239399], UPCB! [accession no. 99412]) . (Figures 17–18).

Comments:— This species is distinguishable by the combination of nodes with interpetiolar flaps (0.5–3 mm long) (Fig. 17D), glabrous hypanthia and calyces, calyces with callose dorsal projections (Fig. 17H)), spreading, fuchsia corollas, isomorphic stamens, stamen connectives with two appendages (Fig. 17E), one triangular descending dorso-basal appendage, and other dorsal appendage as a mere hump (rarely inconspicuous). Among Peruvian species, M. callosa most closely resembles M. zunacensis but differs by the projections on the insertion of the petioles with the leaf blades [absent vs. present (scutum)], petiole length (10–22 mm vs. 25–50 mm), and the dorsal projections on calyces (callose vs. absent). A detailed comparison of M. callosa with other related species can be found in Fernandez-Hilario et al. (2022).

Distribution and phenology:— Meriania callosa is endemic to northern Peru (Department of Amazonas) and grows in montane forests at 1880–1970 m (Fig. 9). It has been collected in flower in April and November, and fruit in August and November.

Specimens examined:— PERU. Amazonas: Prov. Bongará, Dist. Yambrasbamba, ruta desde CP Santa Rosa hacia bosque El Toro, 1970 m, 05°40’09.22”S, 77°55’30.05”W, 11 Nov 2020 (fl. bud, fr.), R. Fernandez-Hilario et al. 2056 (HOXA!, MOLF!, NY!, UPCB!); Prov. Rodríguez de Mendoza, Dist. Mariscal Benavides, CP Izcuchaca, 1880 m, 06°19’40”S; 77°31’05”W, 30 Aug 1998 (fr.), R. Vásquez & J. Campos 25339 (NY!), same locality, 11 Apr 2001 (fl.), H. van der Werff et al. 16941 (NY!, USM!) .