18. Meriania penningtonii Rob.Fern., R.Goldenb. & Michelang., Nordic J. Bot. 39(3)-e02669: 2 (2021).

Type:— PERU. San Martin [Amazonas]: Rioja to Pedro Ruíz, border with Amazonas [near to CP Buenos Aires], 1800 m, 05°45’S, 77°40’W, 04 Dec 2003 (fl.), T.D. Pennington, R.T. Pennington & A. Daza 17639 (holotype: MOLF! [barcode 000003]; isotypes: E! [barcode E00177820], K! [barcode K000544378], MOLF! [barcodes 000004, 000005]) . (Figures 42–43).

Comments:— Meriania penningtonii is clearly distinguished by its quadrate and 4-winged internodes (the wings projections up to 3.5 mm high) (Fig. 43B), the nodes without interpetiolar flaps, callose dorsal projections on the calyces, spreading, reddish-purple corollas, and stamen connectives with dorsal appendages as mere humps (Fig. 42E). Other species such as M. tetragona (Ecuador and Peru) and M. nobilis Triana (Colombia) have quadrangular-winged internodes, but none of these species have evident winged projections like M. penningtonii . Additionally, the dorsal projections on the calyx are whitish and much lighter than the rest of the calyx and hypanthium when dry (Fig. 42G), which makes M. penningtonii easily recognisable. Meriania callosa, M. fantastica Alvear, Humberto Mend. & Almeda, M. rigida and M. sessilifolia have spreading corollas and calyces with callose dorsal projections, but in these species the projections are never whitish when dry. A detailed comparison of M. penningtonii with other related species can be found in Fernandez-Hilario et al. (2021).

Distribution and phenology:— Meriania penningtonii is endemic to northern Peru (Department of Amazonas) and occurs in montane forests at 1800–2180 m (Fig. 44). It has been collected in flower in July and December.

Specimens examined:— PERU. Amazonas: Prov. Bongará, Dist. Yambrasbamba, bosque “El Toro” de la Comunidad Campesina de Yambrasbamba, 2088 m, 05°39’16.9”S, 77°54’36.9”W, 23 Jul 2015 (fl. bud), S. Almeyda & C. Castillo 18 (MOLF!, UPCB!), Abra Patricia-Alto Nieva Private Conservation Area, Abra Patricia, from the highway to the mountain top, 2180 m, 05°40’03.67”S, 77°46’14.56”W, 20 Jul 2014 (fl.), Y.F. Deng et al. 1660 (USM!), inmediaciones del CP Miraflores, 1960 m, 05°42’16.44”S, 77°55’54.18”W, 10 Nov 2020 (fl. bud), R. Fernandez-Hilario et al. 2030 (HOXA!, MOLF!, NY!), ruta desde CP Santa Rosa hacia bosque El Toro, 2000 m, 05°40’15.03”S, 77°55’26.60”W, 11 Nov 2020 (fl.), R. Fernandez-Hilario et al. 2058 (HOXA!, MOLF!, NY!, UPCB!), ruta desde CP La Florida hacia finca de Don Ilario, 2100 m, 05°40’21.68”S, 77°57’16.02”W, 12 Nov 2020 (fl.), R. Fernandez-Hilario et al. 2072 (HOXA!, MOLF!, UPCB!) .