Costus callosus Maas & H.Maas, 2023

Maas, Paul J. M., Maas-van de Kamer, Hiltje, Andre, Thiago, Skinner, David, Valderrama, Eugenio & Specht, Chelsea D., 2023, Eighteen new species of Neotropical Costaceae (Zingiberales), PhytoKeys 222, pp. 75-127 : 75

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.

Type.

Colombia, Chocó: Mun. San José del Palmar, mouth of Río Torito (affluent of Rio Habita ), Finca Los Guaduales , 730-830 m, 4 Mar 1980, E. Forero, Jaramillo-Mejía, 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 × 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 × 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 × 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 × 25 mm, 3-lobulate, lobules red, 5-6 mm long; stamen yellow, 35-40 × 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, Chocó) (Fig. 21F ).

Habitat and ecology.

In forests, at elevations of 0-1300 m. Flowering year-round.

Vernacular names.

Panama: Caña agria (Kuna).

Etymology.

Costus callosus sp. nov. has been named after the very conspicuous thickened callose zone on its bracts.

Paratypes.

Costa Rica. Alajuela: Volcán Arenal, Funk 10490 (MO). Heredia: path beyond Río Sucio, Braulio Carrillo, 400 m, 4 May 1984, Gómez Pignataro et al. 21201 (MO); Cantón de Sarapiquí, Llanura de Tortuguero, ca. 5 km NE of Puerto Viejo, NE side of Río Sucio, 50 m, 5 Oct 1996, Hammel et al. 20494 (INBIO, MO, U, 2 sheets); Cantón de Sarapiquí, Cuenca del Sarapiquí, 5 km NE of Puerto Viejo, NE side of Río Sucio, 50 m, 22 Sep 1996, Hammel et al. 20694 (INBIO, MO). Limón: 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 Río 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 José, 500 m, May 1992, Lücking 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). Chiriquí: 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 Chiriquí Grande, 1100 m, 22 Oct 1985, LaFrankie 85-38 (MO, U). Darién: Parque Nacional del Darién, along S branch of Río 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 Río 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 Chocó 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). Chocó: Carretera Panamericana, between Río San Pablo and Río Pató, 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.

Figures

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.

Figure 21. Distribution maps for new species of Costaceae: Chamaecostus - Costus douglasdalyi A Chamaecostus manausensis Maas & H. Maas B Costus alfredoi Maas & H. Maas C Costus alleniopsis Maas & D. Skinner D Costus alticolus Maas & H. Maas E Costus antioquiensis Maas & H. Maas F Costus callosus Maas & H. Maas G Costus cochabambae Maas & H. Maas H Costus convexus Maas & D. Skinner I Costus douglasdalyi Maas & H. Maas.