Phlegmariurus dichotomus (Jacquin) W.H. Wagner (1993: 305)

Øllgaard, Benjamin & Testo, Weston, 2021, The Lycopodiaceae of Panamá, Phytotaxa 526 (1), pp. 1-66 : 18-21

. ­­­ Phlegmariurus dichotomus (Jacquin) W.H. Wagner (1993: 305) . Fig. 7C

Lycopodium dichotomum Jacquin (1762: 314) .— Huperzia dichotoma (Jacquin) Trevisan (1874: 248) .— Urostachys dichotomus (Jacquin) Herter (1922: 249) . Type:—Fide Proctor (1977: 28): Jacquin (1776: t. 45), an authentic specimen in BM (Exemplar, quod collegi in insula Martinica, et quod iconi inservitt mihi olim) lectotype.

Lycopodium gramineum Spring (1849: 19) .— Urostachys gramineus (Spring) Herter (1949a: 63) . Type:— ECUADOR. Prov. Guayaquil: Jameson s. n. (K holotype).

Lycopodium barbatum Christ (1905: 254) ; non Kaulfuss (1824: Selaginella ).— Urostachys barbatus (Christ) Nessel (1939: 30) . Type:— COSTA RICA: Wercleì s. n. (P [Herb. Christ] holotype; BONN [Herb. Nessel 7, fragment] isotype).

Lycopodium chamaepeuce Herter (1909a: 50) .— Urostachys chamaepeuce (Herter) Herter (1923: 164) . Type:—None designated.

Urostachys chamaepeuce (Herter) Herter var. urbanianus Herter (1923: 164) . Type:— GRENADA: Annandale on cacao trees, February 1906, Broadway 3457 (B n.v.; NY), 3458b (B n.v.).

Urostachys lindeneri Nessel (1940 a: 164 excluding figure).— Huperzia lindeneri (Nessel) Holub (1985: 74) . Type:— GUATEMALA: Chilion, Mazatenango, 1866–1878, Bernoulli & Cario s. n. (BONN-Nessel 350 holotype).

Urostachys schlechtendalii Nessel (1940 a: 153) .— Huperzia schlechtendalii (Nessel) Holub (1985: 76) . Type:— MEXICO: “Guaveyma”, Wagner s.n. (BONN-Nessel 349 p. p. holotype).

Plants pendent or recurved from an erect base, lax to subrigid, sparsely to densely and spreadingly branched, usually to 25 (–50) cm long. Shoots homophyllous, almost equally thick throughout, 20–25 mm in diameter including leaves near the base, usually tapering to (10–) 15 mm in densely sporangiate terminal divisions. Stem excluding leaves 2–3 mm thick at the base, sometimes tapering to 1.5–2 mm, usually almost concealed by leaves, ridged by decurrent leaf bases, sporangiate from 5–15 cm above the base and upward, usually 3–5 times dichotomous. Leaves borne in alternating whorls of 5–6, these 1–2 mm apart, forming 10–12 indistinct longitudinal ranks, spreading to ascending, usually somewhat obliquely falcate, in terminal divisions ascending to somewhat appressed, or appressed throughout, linear-subulate, gradually tapering from the base, (8–) 10–15 (–17) × 0.7–1 mm, almost flat, with slightly prominent vein above, with flat or slightly revolute margins, abaxially with slightly to sharply prominent vein, soft-herbaceous, usually twisted at the base. Leaf bases long and prominently decurrent, green, as wide as, or wider than the lamina, with sharply prominent vein. Sporangia 1–1.5 mm wide.

­­­ Distribution:— Florida, Central America, West Indies, Colombia, Venezuela, Ecuador, Galapagos Islands, Peru, Bolivia, Brazil.

­­­ Habitats:— Usually epiphytic in lowland, riverine, and premontane forests. Elev. 0–2300 m elev.

­­­ Notes:— Plants usually rather short and recurved to pendulous, with linear, densely crowded, usually basally twisted, falcately ascending leaves. This is the most widespread and variable species of the group. Closer study of the material referred to this species may show the presence of more than one taxon, especially in the northern part of the range, because there is considerable variation in the thickness of stems, leaf length and direction, and compactness of the plants. However, the correlation of the variation with growth conditions is uncertain at this point.

Urostachys mortonii Herter (1930: 108) .— Huperzia mortonii (Herter) Holub (1985: 75) .— Syntypes from Guatemala, n. v., appears to be a synonym of P. dichotomus .

­­­ Specimens­­­examined:—Bocas­­­del­­­ Toro: Wedel 190 (MO). Forest near headwaters of Río Culebra ca. 5 km ENE of Cerro Pate Macho, 1158 m, Hammel 6145 (MO). Alto Río Guabo, Atlantic slope N of Fortuna Dam site, 500–650 m, Foster et al. 15780 (PMA). Distr. Changuinola, orillas del Quebrada Bonyic, Hernández et al. 490 (PMA). Distr. Changuinola, Guayacan, 230 m, Laube et al. 362 (PMA). Canal­­­ Zone: Drowned forest of Quebrada Tranquilla and its branches, 70–80 m, Dodge & Allen 17503 (MO, US). Valley of Río Puente, between Tunnel and Natural Bridge, Dodge & Allen 17321 (US). Barro Colorado Island, Croat 8029, 8521 (MO). Near Madden Dam, 100 m, Dodge 16566 (US). Barro Colorado Island, Shattuck 841 (F). Baillemona, Stevens 660 (US) Barro Colorado Island, Shannon 1, Foster 900 (photo DUKE). Barro Colorado Island, Kenoyer 60 (photo US). Chiriquí: La Fortuna hydroelectric project; in forest along ridge top north side of river, 1200 m, Hammel 2195 (MO). Trocha 3 de noviembre, Alto de Guayabo—linea divisora continental, 1050–1650 m, Correa et al. 2864 (PMA). North side of Cuesta de Piedra, 10 km S of El Hato del Volcán, on road to Concepción, 1040 m, Nee 10076 (MO). Paraiso, Wagner 645 (M). 0.8 km up the main road from the center of the town Cerro Punta, then 1.2 km SW along side road on ridge beyond end of the road, primary forest, 2100–2300 m, Lellinger et al. 1925 (photo US). San Bartolo Limité, 18 km W of Puerto Armuelles, 450 m, Busey 588 (MO). Ca. 5 km S of Boquete, Dressler & Williams 4014 (PMA). Bugaba, Camarón, 612 m, Martínez et al. 1994 (PMA). Coclé: Road La Pintada—Coclesito, 600 m, Hamilton & Davidse 2864 (MO). Between Continental Divide above El Cope and El Petroso sawmill and the Río Blanco to the N, a 5 hr hike, 152 m, Sytsma et al. 2436 (MO). Valle de Antón, 700 m, Hunter & Allen 317 (US). Between continental divide above El Cope, and El Petroso sawmill, and Río Blanco to the North, 150 m, Sytsma et al. 2436 (MO). Penonomé and vicinity, Williams 1162 (NY). Colón: 20 km from Transisthmica Hwy. on Santa Rita Ridge, SE facing slope, Río Gatun drainage, 400 m, Knapp & Schmalzel 1769 (AAU). Walking upstream from the bridge over the Río Guanche, Antonio 4788 (MO). Ca 4 km SW of Portobelo, 20 m, Croat 14188 (MO). Parque Nacional Portobelo, Ribera del Río Guanche, Galdames & Aranda 4112 (PMA). Porto Belo, 5–200 m, Maxon 5821 (US) N side of Río Guanche, 0.5–1 km upstream from Puerto Pilón–Portobelo road, 5–30 m, Née 7116 (MO). Semi-swampy floodplain near bridge over Río Buenaventura, near Portobello, Foster 1790 (photo DUKE). Parque Nacional San Lorenzo, 130 m, Sánchez 42 (PMA). Darien: Río Morti, 250 m, Duke 14307 (MO). Campamento Buena Vista, Río Chucunaque above confluence with Río Turquesa, near Quebrada Felix, Stern et al. 956 (MO). Panamá: Capira, Lower slopes and trail to Cerro Campana, Witherspoon 8393 (MO). Near Salamanca, gorge of Río Pequení, 70–80 m, Dodge et al. s.n. (MO). Panamerican hwy El Llano—Río Mamoni, Duke 5652 (MO). Veraguas: Distr. Montijo, Isla Coiba, Soledad, Ensenada María, Araúz et al. 667 (PMA). Parque Nacional Coiba, Estero Boca Grande, Galdames et al. 4050 (PMA). P.N. Coiba, Jicarón, 5 m, Ibañez et al. 3704 (PMA).