Spathacanthus hoffmannii Lindau, Bull. Herb. Boissier 3: 370. 1895

Burgos-Hernandez, Mireya & Castillo-Campos, Gonzalo, 2020, Taxonomic revision of the Mesoamerican genus Spathacanthus (Justicieae, Acanthoideae, Acanthaceae), PhytoKeys 144, pp. 31-55 : 31

Spathacanthus hoffmannii Lindau, Bull. Herb. Boissier 3: 370. 1895 Figs 4 , 5

Type.

Costa Rica. Alajuela: prope Aguacate, Aug 1857, C. Hoffmann 842 (holotype: B destroyed, photos F!, GH!, US!).

Description.

Small trees or shrubs, up to 8 m height, highly branched, internodes glabrous. Stems quadrate to flattened when young, glabrous or pubescent at nodes with flexuose eglandular trichomes. Leaves subsessile to rarely short petiolate, petioles 2-5 mm long, blades elliptic to obovate-elliptic, 72-285 mm × 25-110 mm, apically acute to acuminate, basally acute, margin undulate, glabrous on both surfaces. Inflorescences terminal, sometimes axillary, rachis pubescent; bracts triangular to lanceolate, subulate, 1-8 mm × 1-1.3 mm, abaxial surface glabrous; bracteoles lanceolate to subulate, 2.5 mm × 1-1.5 mm, abaxial surface glabrous. Flowers pedicellate, pedicels 9 mm long, glabrous; calyx green before fruiting, 10-40 mm × 10-16 mm, abaxially glabrous, equally divided into 2 prominent elliptic to obovate-elliptic segments; each segment 11-30 mm long; anterior segment entire, the posterior entire to bilobed; triangular lobes, 1.5-5 mm long, acute to apiculate; corolla white, 52-110 mm long × 30-50 mm wide, externally glabrous and internally pubescent, throat 35-50 mm long × 9-20 mm in diameter near midpoint, upper lip 15-26 mm long, bilobed, lobes ovate to elliptic, 10-20 mm × 11-18 mm, lower lip 18-25 mm long, three-lobed, lobes ovate to elliptic, 15-20 mm × 12-16 mm. Stamens whitish, longer pair 24-34 mm long from the base to the apex of the thecae, shorter pair 18-28 mm long; anthers dithecous, thecae 4-6 mm long; style glabrous 44-59 mm long; stigma lobes 0.3-0.6 mm long. Capsule 50-89 mm long, stipe 20-40 mm long, head 22-39 mm long. Seeds subcordate, 7.5-13 mm × 7.5-11 mm, surface roughened.

Distribution, habitat and phenology.

Spathacanthus hoffmannii is known only from Costa Rica where it has been reported from all provinces (Fig. 1A ). It occurs along the banks of watercourses and on cliffs in humid forests, rain forests and cloud forests at 350 to 1750 m a.s.l. Flowering takes place from January to October, fruiting from December to September.

Specimens examined.

Costa Rica. Alajuela: Est. Biol. Reserva Forestal de San Ramón, valley of Río Lorencito, Burger et al. 12439 (F); Bajos de Jamaical, Reserva de San Ramón, I. Chacón 1768 (CR, DUKE); finca Los Ensayos ca. 11 mi NW of Zarcero, 900 m a.s.l., 15 Aug 1977, T.B. Croat 43516 (MO); San José de Naranjo, I. García s.n. (CR, F); río San Lorencito, límite E de la Reserva Forestal de San Ramón, J. Gómez-Laurito 10263 (CR, F); Est. Biol. Res. Forestal de San Ramón, valley of río Lorencito on Caribbean slope, J. Gómez-Laurito & K. Swangel 12439 (CR); Reserva Forestal de San Ramón, río San Lorencito, 800-1000 m a.s.l., 05 Dec 1983, G. Herrera 362 (CR, MEXU, MO, US); Buena Vista de San Carlos, L. Holdridge 6790 (CR); Quebrada Lajas, finca Los Ensayos, Buena Vista de San Carlos, A. Jiménez M. 2319 (CR, F, MO, NY); near road to Laguna Hule, R. Lent 3243 (CR, F, MO); Cordillera de Tilarán, río La Balsa, 500 m a.s.l., 07 Mar 1994, V. Ramírez & Q. Jiménez 273 (CR, MO, NY); road to Colonia Virgen del Socorro, barranca of río Sarapiquí, 700-800 m a.s.l., 08 Aug 1979, W. Stevens 13547 (DUKE, F, MEXU, MO). Cartago: carretera entre Turrialba y Siquirres, a la vera del río Chitaría, J. Gómez-Laurito 6801 (CR, USJ); cerros de La Carpintera, 1600 m a.s.l., 14 Oct 1973, R, Lent 3657 (CR, F, MO); 13 km E of Turrialba on hwy to Limón, canyon of Río Chitaría, R. 750-800 m a.s.l., 10 May 1983, Liesner et al. 15444 (CR, DUKE, MEXU, MO); above Turrialtica restaurant, 36.5 km from Turrialba, R. Read & G. Daniels 74-63 (US); vicinity of Pejivalle, P. Standley & J. Valerio 46759 (F, US); 9.5 mi E of Turrialba, on rocky banks of río Chitaría, 762 m a.s.l., 12 Aug 1977, G. Webster 22253 (DUKE, F, MEXU). Guanacaste: El Silencio, near Tilarán, P. Standley & J. Valeria 44745 (F, US). Heredia: Virgen del Socorro, río Sarapiquí, Cariblanco, 600-800 m a.s.l., 31 Aug 1983, I. Chacón & G. Herrera 1211 (CAS, CR, DUKE, MO); barranca del río Sarapiquí, Colonia Virgen del Socorro, J. Gómez-Laurito 9868 (CR, F); canyon of río Sarapiquí, just upstream from bridge on rd to La Virgen del Socorro, 05 Aug 1983, B. Hammel 13304 (CR, DUKE, F, MO); camino a la Colonia de la Virgen del Socorro, rumbo a Pto. Viejo, L. Poveda 985 (CR); Vara Blanca de Sarapiquí, N slope of Central Cordillera, 1500-1750 m a.s.l., Jul 1937, A. Skutch 3325 (K, MO, NY, US). Limón: La Florida, voie ferrée atlantique, H. Pittier 11286 (US); río Hondo, H. Pitiier 16641 (K). Puntarenas: Miramar, Quebrada seca, cerro Zapotal, 18 Sep 1985, L.D. Gómez et al. 23990 (CAS, CR, DUKE, MEXU, MO). San José: Terrazú, Pérez Zeledón. estribaciones del cerro Diamante, 500-600 m a.s.l., 22 Sep 1998, A. Estrada et al. 1730 (MEXU); zona protectora La Cangreja, Santa Rosa de Puriscal, Q. Jiménez 482 (CR, K); zona protectora cerro Turrubares, Q. Jiménez 543 (CR).

Figures

Figure 1. Distribution of the Mesoamerican genus Spathacanthus Baillon. A Distribution of S. hahnianus and S. hoffmannii B distribution of S. magdalenae and S. parviflorus.

Figure 4. Spathacanthus hoffmannii Lindau. R. Liesner, E. Judziewicz & B. Perez G. 15444 (MEXU), Costa Rica: Cartago.

Figure 5. Spathacanthus hoffmannii Lindau. Image modified from Durkee (1986) Flora Costaricensis, No. 18, page 19. The image shows an elliptic leaf of S. hoffmannii, flowers with a five-lobed corolla and the 2 - segments of calyx equally or subequally divided, with its large woody fruit.