Eighteen new species of Neotropical Costaceae (Zingiberales) Author Maas, Paul J. M. Naturalis Biodiversity Centre, Botany, P. O. Box 9517, 2300 RA Leiden, Netherlands Author Maas-van de Kamer, Hiltje Naturalis Biodiversity Centre, Botany, P. O. Box 9517, 2300 RA Leiden, Netherlands Author Andre, Thiago https://orcid.org/0000-0003-4148-3662 Universidade de Brasilia, Departamento de Botanica, Campus Universitario Darcy Ribeiro, Asa Norte, Brasilia (DF), Brazil Author Skinner, David https://orcid.org/0000-0003-4585-925X Le Jardin Ombrage, Tallahassee, (Private botanical garden, Botanic Gardens Conservation International - BGCI - registration ID 50148), Florida, USA Author Valderrama, Eugenio Cornell University, Section of Plant Biology and the L. H. Bailey Hortorium, School of Integrative Plant Science, Ithaca, NY, USA Author Specht, Chelsea D. https://orcid.org/0000-0001-7746-512X Cornell University, Section of Plant Biology and the L. H. Bailey Hortorium, School of Integrative Plant Science, Ithaca, NY, USA cdspecht@cornell.edu text PhytoKeys 2023 2023-03-22 222 75 127 http://dx.doi.org/10.3897/phytokeys.222.87779 journal article http://dx.doi.org/10.3897/phytokeys.222.87779 1314-2003-222-75 348E6053A6D55787993694B23682FDE9 Costus callosus Maas & H.Maas sp. nov. Diagnosis. Costus callosus sp. nov. (Fig. 7 ) is most similar to C. curvibracteatus , differing by the inflorescence mostly produced terminally on a leafless shoot, with soon withering sheaths and bracts with a very long callus. Figure 7. Costus callosus Maas & H.Maas A plant in habitat B inflorescence C separate flowering shoot D bract and flower details showing very long bract callus E, F cultivated plant A, C, D observation from Willie Mazu site, Bocas del Toro, Panama B plant in cultivation at Lyon Arboretum 2003.0125, collected in Costa Rica by Alan Carle E, F plant observed at Reserva Natural Nirvana, Valle del Cauca, Colombia. Photos A, C, D by Dave Skinner, B by John Mood, E, F by Paul Maas. Type . Colombia , Choco : Mun. San Jose del Palmar , mouth of Rio Torito (affluent of Rio Habita ), Finca Los Guaduales , 730-830 m , 4 Mar 1980 , E. Forero , Jaramillo-Mejia , Espina Z. & Palacios 6668 ( holotype COL, 3 sheets; isotypes MO-1456278, U1607067, U1607068, U1607069, U1610613) . Description. Herb 0.5-3 m tall. Leaves sheaths 15-30 mm diam; ligule obliquely truncate, 10-30 mm long, distally black to dark purple, with a minute, salient rim; petiole 5-20 mm long; sheaths, ligule and petiole glabrous, sparsely puberulous, or densely villose; lamina narrowly elliptic, 25-50 x 7-16 cm, adaxially sparsely to rather densely villose to puberulous, abaxially rather densely villose, base acute, apex acuminate (acumen 5-15 mm long). Inflorescence ovoid to subglobose, 6-23 x 6-12 cm, terminating a leafless shoot 20-90 cm long, rarely terminating a leafy shoot ( Knapp & Vodicka 5524 ), sheaths withering and completely or partly falling off with age, obliquely truncate, 4-10 cm long, glabrous, sparsely puberulous to densely villose; bracts, bracteole, calyx, ovary, and capsule glabrous to rather densely puberulous. Flowers abaxially oriented; bracts orange-red, red, or yellow, coriaceous, ovate-triangular, 4-7 x 2.5-4 cm, apex acute to obtuse, more or less curved outwards to patent in living plants, callus 8-25 mm long, margins wooly in living material; bracteole boat-shaped, 20-30 mm long; calyx red, 10-18 mm long, lobes deltate, 2-8 mm long; corolla orange to yellow, ca. 50 mm long, glabrous, lobes elliptic, ca. 30 mm long; labellum yellow, lateral lobes rolled inwards and forming a tube ca. 10 mm diam, elliptic when spread out, ca. 35 x 25 mm, 3-lobulate, lobules red, 5-6 mm long; stamen yellow, 35-40 x 12-15 mm, slightly exceeding the labellum, apex orange-red, acute, anther 9-10 mm long. Capsule ellipsoid to obovoid, 8-15 mm long. Distribution. Costa Rica, Panama, Colombia (Antioquia, Choco ) (Fig. 21F ). Habitat and ecology. In forests, at elevations of 0-1300 m. Flowering year-round. Vernacular names. Panama: Cana agria (Kuna). Etymology. Costus callosus sp. nov. has been named after the very conspicuous thickened callose zone on its bracts. Paratypes. Costa Rica. Alajuela : Volcan Arenal, Funk 10490 (MO). Heredia : path beyond Rio Sucio, Braulio Carrillo, 400 m, 4 May 1984, Gomez Pignataro et al. 21201 (MO); Canton de Sarapiqui , Llanura de Tortuguero, ca. 5 km NE of Puerto Viejo, NE side of Rio Sucio, 50 m, 5 Oct 1996, Hammel et al. 20494 (INBIO, MO, U, 2 sheets); Canton de Sarapiqui , Cuenca del Sarapiqui , 5 km NE of Puerto Viejo, NE side of Rio Sucio, 50 m, 22 Sep 1996, Hammel et al. 20694 (INBIO, MO). Limon : Hacienda Tapezco-Hacienda La Suerte, 29 air km W of Tortuguero, 40 m, 24 Aug 1979, Davidson & Donahue 8770 (CR, LAM, U); Parque Nacional Braulio Carrillo, W side of Rio Sucio, 450 m, 4 Aug 1989, Hammel et al. 17668 (MO, U); Braulio Carrillo National Park, Quebrada Gonzales section, ca. 40 km NNE of San Jose , 500 m, May 1992, Luecking s.n. (U). Panama. Bocas del Toro : 2 miles below the divide along main highway, 500 m, 23 Jun 1986, Kress et al. 86-1978 (MO). Chiriqui : behind Vivero Forestal de Boquete, 12 km N of Los Planes de Hornito, IRHE Fortuna, 1100-1200 m, 17 Jun 1982, Knapp & Vodicka 5524 (U); near Fortuna dam, from Continental Divide to Chiriqui Grande, 1100 m, 22 Oct 1985, LaFrankie 85-38 (MO, U). Darien : Parque Nacional del Darien , along S branch of Rio Pucuro, near Tacarcuna, ca. 18 km E of Pucuro, 600-800 m, 25 Oct 1987, Hammel et al. 16513 (MO, U); 0-2 miles E of Tres Bocas, along the shortest headwater of Rio Cuasi, 28 Apr 1968, Kirkbride & Duke 1180 (MO, U). Panama : Altos de Pacora, ca. 20 km NE of Cerro Azul, 750 m, 19 May 1972, Dressler 4190 (U, 3 sheets); summit of Cerro Jefe, 26 Aug 1967, Hayden 1020 (MO, 2 sheets); 5-6 hours walk from Choco village, Serrania de Maje, 650-800 m, 31 Mar 1982, Knapp et al. 4519 (MO, U); Altos de Pacora, 750 m, 2 Sep 1974, Maas et al. 1548 (U, 2 sheets). Colombia. Antioquia : Mun. Amalfi, between Amalfi and Fraguas, 1220-1300 m, 14 Feb 1989, MacDougal et al. 4020 (HUA). Choco : Carretera Panamericana, between Rio San Pablo and Rio Pato , 23 Apr 1979, Forero et al. 5765 (COL, MO, U, 2 sheets). Cultivated Material. Colombia, Valle del Cauca, Mun. Palmira, Reserva Natural Nirvana, 13 Jul 2018, Maas et al. 10688 (L, 3 sheets). Notes. Maas (1977) already suspected this species differed from C. curvibracteatus Maas, although they share many ligule and bract characters. The presence of a separate, leafless flowering shoot with soon withering sheaths and the presence of a distinct callus on the bracts convinced us that it is worthy of recognition as a separate species. Material recently collected ( Maas et al. 10688 ) in the Reserva Natural Nirvana, Valle del Cauca, Colombia, made it possible to add all flower details to the description.