Monographs Details: Asplenium serratum L.
Authority: Morton, Conrad V. & Lellinger, David B. 1966. The Polypodiaceae subfamily Asplenioideae in Venezuela. Mem. New York Bot. Gard. 15: 1-49.
Family:Aspleniaceae
Scientific Name:Asplenium serratum L.
Description:Species Description - Rhizomes large and massive, epiphytic, covered with masses of densely tomen-tose roots, paleaceous at apex with thin, brown, linear-lanceolate, clathrate scales; fronds numerous, fasciculate, erect, nearly sessile, the short thick stipes rarely more than 2 cm long; blades simple, unlobed, linear-oblanceolate, up to 100 cm long, 7-14 cm broad (or less in depauperate or juvenile specimens) , rather thin in texture, bright green, abruptly caudate at apex to acuminate but not long-attenuate, narrowed toward base, subentire to conspicuously serrate or sometimes crenulate; veins once-forked near the base, at an angle of 66°-72° with the midrib; sori elongate, linear, extending one-half to two-thirds the distance to the margin.

Distribution and Ecology - General distribution. West Indies; Mexico to Bolivia and Argentina. In the Venezuelan states of Nueva Esparta, Terr. Delta Amacuro, Sucre, Bolivar, and Amazonas.

Discussion:

Asplenium nidus sensu Raddi, Opusc. Sci. Bologna 3: 290. 1819, non L., 1753.

? Asplenium longifolium Schrader, Goett. Gelehrte Anzeig. 1824: 870. 1824. No specimens or locality cited.

Asplenium subsessile Cav. Descr. Pl. 254. 1802. Type: Andes, Nee (MA, not seen). Christensen examined the type and found that the locality originally cited “Palapa, Mariannas,” was surely erroneous, and that the specimen presumbly came from the Andes.

Asplenium crenulatum Presl, Tent. Pterid. 10G. 1836. Based on A. nidus sensu Raddi, the type thus Mandiocca and Corcovado, Brazil, Raddi.

Asplenium schomburgkianum Klotzsch, Linnaea 20: 350. 1847. Syntypes: British Guiana, Schomburgk 265, Rob. Schomburgk 323 (isosyntype US) .

Type. There are two sheets in the Linnaean Herbarium (one of them, no. 1250-7, labelled serratum in the hand of Linnaeus, photograph US), both representing A. angustum Swartz. It seems likely that they were added to the herbarium after 1753 and did not form part of the original concept of the species. Linnaeus cited Plumier, Lingua Cervina longo lato serratoque folio. Plum. amer. 27. t. 39, Petiver fil. 106. t. 6, f. 7, and Sloane Jam. 14. hist. 1. p. 72, all of which doubtless represent A. serratum in the traditional sense. The Sloane reference may be designated as lectotype, since there is probably an authenticating specimen extant in the British Museum.

Most of the specimens from the Guayana Highlands are smaller than typical West Indian specimens. Possibly distinct is A. schomburgkianum Klotzsch (an earlier name perhaps A. subsessile Cav.), which has the fronds only 30-50 cm long, 3-5 cm broad, gradually attenuate below, obtuse to acute-cauclate at the apex, the margins crenate-serrate toward the apex and generally entire below.

Most of the specimens from the Guayana Highlands are smaller than typical West Indian specimens. Possibly distinct is A. schomburgkianum Klotzsch (an earlier name perhaps A. subsessile Cav.), which has the fronds only 30-50 cm long, 3-5 cm broad, gradually attenuate below, obtuse to acute-cauclate at the apex, the margins crenate-serrate toward the apex and generally entire below. and the rhachises often stramineous or merely gray, passing into shallowly grooved, nearly obsolete stipes.