A new species of Adiantum from Cuba.

ABSTRACT.--Adiantum alomae is described from eastern Cuba. It is characterized by pubescence on all parts of the leaves and its small size. Its habitat is also distinctive, occurring on limestone cliffs and walls, usually facing and very near the sea, receiving salt spray. A key is given to differentiate it from the related Cuban endemic Adiantum sericeum, and illustrations of the distinctive characteristics of both species are presented.

KEY WORDS.--Adiantum alomae, Cuba, new species

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Adiantum is represented in Cuba by 23 species (Duek, 1971). These species grow mainly in gallery forest and secondary forest, from sea level to ca. 700 m in elevation or in coffee, cacao and citrus plantations. The genus is nearly absent in rain and cloud forests at high elevations.

Two species of Adiantum grow in eastern Cuba in coastal shrub vegetation or on limestone cliffs near or facing the sea. The first is Adiantum alomae, described below, which occurs mainly along the southern coast. The second is A. deltoideum Sw. occurring along the northern coast.

Eaton (1869) described Adiantum sericeum and pointed out that it differed from many other species of Adiantum by the pubescence on all parts of the leaf. Since then, many collections of densely pubescent Adiantum have been gathered in Cuba and identified as A. sericeum. Recent herbarium and field observations, however, suggest that they represent not one but two species: A. sericeum, growing in central and western Cuba, and a new one confined to eastern Cuba, which is here described.

Adiantum alomae Caluff, sp. nov. TYPE.--CUBA. Santiago de Cuba. Castillo del Morro y sus alrededores, en rocas y paredones calizos, localmente abundante, 0-50 m, matorral costero, 14 Jun 2007, Caluff, Shelton, & M. Serguera 6356 (Holotype: BSC!; isotypes: HAC!, HAJB!). Fig. 1 A-I.

Ad A. sericeum D.C. Eaton affinis differt, frondium magnitudine (12-51 x 4-10 cm in A. sericeo autem 5-28 x 1.3-2 cm in A. alomae), laminae architectura (2-3 pinnata in A. sericeo autem 1-2 pinnata in A. alomae), rhizomatis squamarum longitudine (4-20 mm in A. sericeo autem 1.3-5 mm in A. alomae), atque rachium trichomatibus (trichomata densissima, rigida, patentia obscuro-rubescentiaque in A. sericeo, autem sparsa, flexuosa, albescentia usque claro-fusca in A. alomae).

Plants epipetric or rarely terrestrial. Rhizome ascending, ramified, cylindrical, blackish, 2-3 mm in diam., scaly toward the apex, the scales (Fig. 1E) ovate to ovate-lanceolate, brown, 1.3-5 x 0.8-1.2 mm, nearly clathrate, the cells in the basal and medial portion roundish, distally enlarged, basifixed, the base truncate to more or less cordate, denticulate, the teeth (Fig. 1F) recurved or incurved, concolorous, usually conformed by two cells, the apex filiform: fronds (Fig. 1A) numerous, fasciculate, 5-30 cm long; laminae linear-lanceolate, 1-pinnate or occasionally 2-pinnate in the largest medial pinnae, 4-24 x 1-3.2 cm, with an apical, the biggest, conform pinna (Fig. 1B-D), usually hairy on both surfaces; stipes cylindrical, 1-6 cm long and 0.2-1.0 mm diam., reddish brown when young, eventually blackish, lustrous, scaly at the very base, hairy throughout like the rachis and pinnae stalks (Fig. 1G), the hairs weak and deciduous, of two types: some numerous, unicellular (Fig. 1I), whitish to clear brown, usually flexuous 0.8-0.9 (1.3) mm long, cylindrical, sometimes paler and flattish, with an enlarged base, others, occasional, found near the pinnae insertion and in the stalks, pluricellular (Fig. 1H), translucent, flattish, flexuous, with some cateniform cells, the septae reddish, up to 3 mm long, scales also present, these, deltate-enlarged, clear brown, lustrous, the base truncate, the cells 2-4 times longer than wide; pinnae 8-16 pairs, stalked 1-3 mm, 0.5-1.7 x 0.4-1.3 cm, alternate, with 3(-5) lobules, the margins entire to shallowly dentate, the base cuneate, lightly oblique, articulate, deciduous, the stalk and its blackish color stopping abruptly in a dilatate, discoid joint, the simple ones never overlapping the rachis, the sterile herbaceous, rounded or with blunt lobes, the fertile ones somewhat contracted, chartaceous, saggitate, the apex and lobules acute; pinnules (if any) 1 or 2, similar to the pinnae but smaller; veins free, flabellate-dichotomous, clear brown, lightly raised over the laminar tissue and hairy on both surfaces; laminar hairs abundant, unicellular, whitish, flexuous, 0.6-0.9 mm long. Sori linear, usually continuous and curved, avoiding the lobe apex; indusia brown to dark brown, entire, with numerous rigid, whitish to clear brown hairs, 0.40.5 mm long; sporangia glabrous; spores tan to yellowish, globose-tetrahedral, retate, 40-45 [micro]m.

[FIGURE 1 OMITTED]

SPECIMENS EXAMINED.--CUBA. Granma: municipio Pilon, Boca de Toro, desembocadura del rio Boca de Toro, suelo calizo, 0-10 m, 19 Mar 1988, Gabriel Brull s/n (HAC; HAJB). Santiago de Cuba: farallon costero, Sardinero, Santiago., 8 Jul 1949, Alain 815 (HAC); Oriente, Florida Blanca, sobre rocas, 10 Jan 1960, Hno. Alain, Acuna, Lopez-Figueiras & Ramos s/n (HAC); playa Sardinero, Justici, Santiago de Cuba, entrando a la playa, sobre paredones calizos, 5 m, matorral xeromorfo costero, 13 Jul 1980, Caluff 920 (BSC); Castillo del Morro de Santiago de Cuba, comun en paredes y resquicios calizos, 50 msm, vegetacion costera, 20 Aug 1979, Caluff & Couso 1 (BSC); playa Sardinero, Reserva Siboney-Jutici, Santiago de Cuba, en rocas y paredones a 1 km de la playa, 10 m, bosque semideciduo microfilo, 29 Feb 2007, Caluff & M. Serguera 6226 (BSC); paredones a la entrada de la playa Sardinero, Santiago de Cuba, 5 m, matorral xeromorfo costero, 19 Mar 1990, Caluff & Shelton 2942 (BSC); alrededores de Santiago de Cuba, Jul 1920, Clemente 131 (HAC); alrededores del Morro, Santiago, 18 Nov. 1937, Clemente 2248 (HAC); sobre una roca en los farallones que rodean a la Playa de Sardinero, Santiago de Cuba, 25 Nov 1951, Lopez Figueiras 315 (HAC); provincia de Oriente, cercanias de la desembocadura del rio San Juan, en la playa de Aguadores, 26 Oct 1952, Lopez Figueiras 1716 (HAC, 3 sheets; HAJB); provincia de Oriente, en farallones del Monte Picote, cercanias del central Miranda, 12 Mar 1955, Lopez Figueiras 2001 (HAC; HAJB); Santiago de Cuba, Morro Castle, 24 7. 1909, Voisard & Boelloz 1556 (HAC). Without locality: 27 Jul 1952, F. G. C. s.n. (HAC); Garcia Canizares s.n (HAJB); Cuba orientali, 1859-1860, Wright 1078 (3 sheets) (HAC).

DISTRIBUTION.--Endemic to the coasts of southeastern Cuba, Santiago de Cuba and Granma Provinces, with a single small population found inland, growing in the karstic belt of the southern side of Sierra de Nipe Mountains.

HABITAT.--Terrestrial or epipetric in dry coastal shrubs vegetation and in semi deciduous microphillous forest, on limestone, in cave entrances, on big rocks, cliffs and old walls, exposed or partially shaded, usually in crevices, facing the sea and receiving the salt spray, 0-50 m elevation; the population inland, on limestone cliffs, usually in open and sunny places, 80-150 m elevation.

Adiantum alomae grows in dry habitats near and commonly facing the sea, receiving the salt spray. The largest population was found in the Morro Castle of Santiago de Cuba and nearby areas, consisting of hundreds of individuals. They grows on old walls, big rocks, around a cave entrance, in the ground. The stone masonry associated with the castle was built using calcareous rocks and terracotta bricks cemented with lime mortar.

Adiantum alomae and A. sericeum are the only two completely hairy species of this genus in Cuba. The hairs cover the stipes, rachises, indusia, and laminar tissue on both surfaces. These species can be distinguished by the following key:

1. Leaves up to 30 x 2.3 cm; lamina 1-pinnate to occasionally 2-pinnate; the simple pinnae not overlapping the rachis; unicellular hairs of the non laminar axes whitish to clear brown, weak, flexnous A. alomae

1. Leaves up to 51 x 10 cm; lamina 2-pinnate to occasionally 3-pinnate; basal acroscopic pinnule of each pinna overlapping the rachis; unicellular hairs of the non laminar axes dark reddish, acicular, rigid, patent A. sericeum

Adiantum alomae and A. sericeum resemble A. tricholepis Fee from the United States, Mexico, and Mesoamerica. They all have denticulate rhizome scales and pubescent laminar tissue on both surfaces. Adiantum tricholepis differs from the other two species by laminae ovate to deltate and 3-4 pinnate, the acroscopic basal pinnules not overlapping the main rachis, the rachis and costae glabrous, and the apex of the stalks not or lightly enlarged (Moran et al., 1995).

Adiantum alomae is similar to A. deltoideum in habitat, small size, and pinna shape. Adiantum deltoideum differs basically in being glabrous and in its distribution, confined to the northern coast of eastern Cuba, growing likewise, on the northern and east coasts of Jamaica, and in Hispaniola (Proctor, 1985).

EPONYMY.---This species is dedicated to Omar Aloma Moreno, Director of the Macradenia Orchid Garden, in Palmira, Cienfuegos Province, central Cuba, who first called my attention to the differences between A. sericeum and the new species.

Because the protologue for Adiantum sericeum is very simple and this rare Cuban endemic is poorly known, a complete description of this species is given.

Adiantum sericeum D. C. Eaton, Botanisch Zeitung. Berlin. 27. 361. 1869.

TYPE.--prope Trinidad, Wright 3950 (isotypes: MBG!; HAC!; NY! {5 sheets}). Fig. 2 A-H.

Plants epipetric or terrestrial. Rhizome ascending, branched, cylindrical, blackish, 2.5-9 mm in diam., densely scaly at the apex, the scales (Fig. 2E) lustrous, concolorous, light brown, deltate-attenuate to deltate-lanceolate, 4-10 x 0.3-1.5 mm, non clathrate, basifixed, the base cordate or lightly so, the margins denticulate (Fig. 2F) with spaced and usually straight, minute, concolorous, one or two celled teeth, the cells in the basal portion rounded to quadrangular, toward the medial and distal portion gradually more enlarged, 2-5 times longer than wide; fronds numerous (Fig. 2A), fasciculate, ca. 51 cm long; lamina 8-38 x 4-10 cm, lanceolate to oblanceolate, 2-pinnate throughout or occasionally 3-pinnate at the base and in the base of the medial largest pinnae, gradually tapered to an apical, conform, simple pinna similar to the apical pinnules of the largest pinnae (Fig. 2. B-D), herbaceous to papyraceous, densely hairy on both surfaces with unicellular, acicular, patent, whitish to deep reddish hairs 0.6-0.9 mm long; stipes 4-13 cm long and 0.6-1.8 mm diam., cylindrical, reddish black, lustrous, scaly at the very base with scales similar to thouse of the rhizome, densely hairy throughout like the rachises and stalks (Fig. 2G), the hairs deciduous, of two types, the commonest acicular (Fig. 2H), unicellular, patent, dark reddish, with a pustular, persistent, enlarged base, ca. 0.7 mm long, and very occasional hairs pluricellular, flexuous, some flattish, translucent with reddish septae, sometimes with some cateniform cells; pinnae 10-17 pairs, alternate, 2-7 x 1-2.7 cm, oblong-attenuate, stalked 2-5 mm, lightly oblique, with a terminal conform, biggest pinnule; pinnules alternate, oblique, articulate, stalked 13 mm, the black color of the stalk suddenly stopping at the pinnule base, leaving a discoid black joint when it falls off, the sterile ones larger, the base cuneate, distally rounded or with the apex and lobules blunt, the outer margins crenate and dentate to lobulate, the fertile ones contracted, saggitate, the apex and lobules acute, lobulate, dentate toward the lobules apex; pinnules of the first order 2-7 pairs, 0.5-1.7 x 0.5-1.7 cm, the basal acroscopic in each pinna overlapping the primary rachis, the apical one always the largest, ca. 2.1 x 2.3 cm; pinnules of the second order similar to those of the first order but more smaller; veins free, flabellate dichotomous, ending in teeth, light brown, lightly raised over the laminar tissue and hairy on both surfaces. Sori oblong, usually discontinuous, curved to straight, avoiding the lobe apex; indusia brown to dark brown, the margin entire, densely hairy with dark reddish, 0.4-0.5 mm long hairs; spores tan, globose-tetrahedral, lightly tuberculate.

[FIGURE 2 OMITTED]

SPECIMENS EXAMINED.--CUBA. Sancti Spiritus: Farallon del Charco de Oro, rio Higuanojo, Area Protegida El Naranjal, Alturas de Sancti Spiritus, en farallones calizos, 300 m, 26 Aug 1994, E. Becqer & E. Martinez 3444 (BSC); alrededores del Hoyo del Naranjal, margenes del rio Higuanojo, Alturas de Sancti Spiritus, prov. Sancti Spiritus, en farallones rocosos, 280 m, bosque siempreverde secundario, 30 Nov 1994, Caluff & Shelton 3854, 3855, 3856 A/B (BSC): cascada Las Cortinas, arroyo La Yaba, finca La Vega, km 40 de la carretera desde Cienfuegos a Trinidad, a unos 200 m de la carretera, en un pedregal de rocas micaceas carbonatadas esquistosas, subiendo por el lado derecho de la cascada, 60-80 m, en bosque semideciduo mesofilo, 3 Feb 2007, Caluff, Shelton & 0. Aloma 6224 (BSC, 16 sheets); Cienfuegos: arroyo Navarro, Mina Carlota, SE de Cumanayagua, Sierra de San Juan, 330 m., 22 Mar 1957, Proctor 29409 (HAC). EASTERN CUBA. Pinar del Rio: paredones del Pan de Azucar, Vinales, del Rio, 5 Feb 1956, Acuna & Morton 20106 (HAC); sobre las rocas, base del mogote Pan de Azucar, Vinales, 9 Oct 1955, Alain 4425 (HAC); La Guira, 7 km de Punta de La Sierra, Pinar del Rio, exploracion sur del mogote, 12 Nov 1972, Bobrov & Cardenas 29409 (HAC); exploracion sur del mogote La Guira, 12 Nov. 1972, Bobrov & Cardenas 29811 (HAC); cercanias de Sumidero, Pinar del Rio, Jul 1012, J. A. Shafer & Leon 3171, (Shaffer 13407) (HAC).

DISTRIBUTION.--Endemic to central Cuba, Sancti Spiritus, and Cienfuegos Provinces, Trinidad and Sancti Spiritus Heights, and western Cuba, Pinar del Rio Province, Sierra de los Organos.

HABITAT.--Semi deciduous and evergreen secondary forest and in karstic (mogote) vegetation, on limestone, in well drained and inclined stony soil, on big rocks and cliffs, usually in crevices, in filtered sun, 60-300 malt., locally common.

Adiantum sericeum grows inland in moderately humid places, typically with pteridophytes such as Adiantopsis rupicola Maxon, Adiantum fragile Sw., Adiantum tenerum Sw., Anemia adiantifolia (L.) Sw., Anemia cuneata Poepp. ex Spreng, Blechnum occidentale L., Lygodium venustum Sw., Pteris longifolia L., Selaginella eatonii Hieron. ex Small, Selaginella spp., Thelypteris dissimulans (Maxon & C. Chr.) C. F. Reed, T. kunthii (Desv.) C. V. Morton, and T. scolopendrioides (L.) Proctor.

ACKNOWLEDGMENTS

I thank Dr. Robbin C. Moran and Dr. Victor Fuentes Fiallo, and the two anonymous referees for revising the manuscript; MSc. Susana Carreras G. for the Latin diagnosis, and Ing. Maite Sergnera N. for spore determination.

LITERATURE CITED

DUEK, J. J. 1971-1972. Lista de las especies cubanas de Lycopodiophyta, Psilotophyta, Equisetophyta y Polypodiophyta (Pteridophyta). Adansonia, ser. 2, 11:559-578, 717-731.

EATON, D. C. 1989. Ein neues Adiantum yon Cuba. Botanisch Zeitung. Berlin. 27. 361.

MORAN, R. C., B. ZIMMER and A. C. JERMY. 1995. Adiantum. In Moran, R.C. & R. Riba. (eds. Pteridofitas). In Davidse, G. M., M. Sousa S. and S. Knapp (eds. generales). Flora Mesoamericana. Vol. 1 Psilotaceae a Salviniaceae. Univ. Nac. Autonoma de Mexico, Inst. de Biologia, Mexico, D. F.

PROCTOR, G. R. 1985. Ferns of Jamaica. British Museum (Nat. Hist.) London.

Jardin de los Helechos de Santiago de Cuba, Centro Oriental de Ecosistemas y Biodiversidad (BIOECO), Carretera del Caney No. 129, La Caridad, Santiago de Cuba, Codigo Postal 90400, Cuba