Danaea Sm., nom. cons.,
Descripción
Rhizomes creeping, green, clothed with thinmargined stipules in two rows on the dorsal part of the rhizomes; roots fleshy, thick; leaf axes with swellings at pinna insertions and occasionally on the stipes; fronds dimorphic; sterile blades 1-pinnate, rarely simple (not in ours), thick-herbaceous to subcoriaceous; veins free, curving at margins into cartilaginous edge; scales on axes and costae, minute scales and trichomidia on veins and lamina; fertile fronds similar in dissection to the sterile, but often with narrower pinnae; sporangia fused into linear, multilocular (20–100 locules) synangia extending from costae to the blade margins, synangia nearly covering the abaxial surfaces; spores bilateral; x=40.A
Forma de vida
TerrestreA
Distribución
México (país) Nativo y no endémicoA
Categoría IUCN
No incluidaB
Categoría NOM-059-SEMARNAT-2010
No incluidaC
Discusión taxonómica
Danaea is a genus of about 30–35 species of the American tropics, in wet montane forests at low to middle elevations. Three species occur in Mexico. The genus is not closely allied to others in the Marattiaceae and is sometimes segregated as a distinct family. Its distinguishing features include its rhizome stipules, fleshy, dimorphic fronds, jointed frond axes, and synangia extending from costa to margin. The family Marattiaceae occupies a basal position within the ferns (Hasebe et al., 1995; Pryer et al., 2001) and has a fossil record back more than 300 million years.
Unplaced Names
Danaea elata Liebm., Mexic. Bregn. 306 (reprint 154). 1849. Type. Mexico. Veracruz: Barranca de la Hacienda de Jovo, Liebmann s.n. [Pl. Mex. 2199, Fl. Mex. 848] (C!).
Danaea media Liebm., Mexic. Bregn. 306 (reprint 154). 1849. Syntypes. Mexico. Veracruz: Barranca de la Hacienda de Jovo, Liebmann s.n. [Pl. Mex. 2185, Fl. Mex. 653, 654, 849, and 850] (C!).
Tuomisto and Christenhusz (Univ. Turku, Finland) are currently studying the systematics of Danaea and have recently concluded (in litt.) that D. elata and D. media, variously treated by several authors (e.g., Underwood, 1909; Smith, 1981; Mickel & Beitel, 1988; Lellinger, 1989; Camus & Pérez-García in Davidse et al, 1995), apply to the same taxon. Tuomisto and Christenhusz believe that this taxon is distinct from the widespread and polymorphic D. nodosa, a name that has been applied to Mexican material with large fronds and nodeless stipes. The types of both D. elata and D. media were collected at the same locality, and it appears likely that D. media is simply a juvenile of D. elata. They were probably described under different names (in the same publication, with a mention that they grow together) because D. media has nodes on the stipes (at least one of the syntypes, possibly a juvenile; see Smith, 1981), whereas D. elata does not. That juveniles often have nodes but adults more often do not is a characteristic shared with populations of D. media elsewhere in Central America. Typical D. nodosa, type from Martinique, does not have nodes on the stipe, even when juvenile, and it also differs from Mexican and Central American material in pinna shape and much bulkier rhizomes. Tuomisto and Christenhusz tentatively plan to use the name D. media for Mexican and Central American plants previously called D. nodosa.
A
Unplaced Names
Danaea elata Liebm., Mexic. Bregn. 306 (reprint 154). 1849. Type. Mexico. Veracruz: Barranca de la Hacienda de Jovo, Liebmann s.n. [Pl. Mex. 2199, Fl. Mex. 848] (C!).
Danaea media Liebm., Mexic. Bregn. 306 (reprint 154). 1849. Syntypes. Mexico. Veracruz: Barranca de la Hacienda de Jovo, Liebmann s.n. [Pl. Mex. 2185, Fl. Mex. 653, 654, 849, and 850] (C!).
Tuomisto and Christenhusz (Univ. Turku, Finland) are currently studying the systematics of Danaea and have recently concluded (in litt.) that D. elata and D. media, variously treated by several authors (e.g., Underwood, 1909; Smith, 1981; Mickel & Beitel, 1988; Lellinger, 1989; Camus & Pérez-García in Davidse et al, 1995), apply to the same taxon. Tuomisto and Christenhusz believe that this taxon is distinct from the widespread and polymorphic D. nodosa, a name that has been applied to Mexican material with large fronds and nodeless stipes. The types of both D. elata and D. media were collected at the same locality, and it appears likely that D. media is simply a juvenile of D. elata. They were probably described under different names (in the same publication, with a mention that they grow together) because D. media has nodes on the stipes (at least one of the syntypes, possibly a juvenile; see Smith, 1981), whereas D. elata does not. That juveniles often have nodes but adults more often do not is a characteristic shared with populations of D. media elsewhere in Central America. Typical D. nodosa, type from Martinique, does not have nodes on the stipe, even when juvenile, and it also differs from Mexican and Central American material in pinna shape and much bulkier rhizomes. Tuomisto and Christenhusz tentatively plan to use the name D. media for Mexican and Central American plants previously called D. nodosa.
A