Diplazium franconis Liebm.
Descripción
Rhizomes erect; rhizome scales dark brown, linear-lanceolate, dull to lustrous, 5–9 X 1–1.5 mm, entire; fronds (50–)70–170 cm long; stipes green to stramineous or brownish, darker at bases, 25–80 cm X (2–)3–6 mm, ca. 1⁄2 the frond length, often with dark brown scales at bases, glabrous distally; blades chartaceous, 2-pinnate to 2-pinnate-pinnatifid, 30–100 X 25–70 cm, ovatelanceolate, apices pinnatifid, lacking buds; rachises glabrous or occasionally with papillae ca. 0.05 mm long in adaxial grooves; pinnae stalked 5–7 mm toward their bases, sessile or adnate distally, to ca. 6 free pairs, (10–)15–26 X 3–9 cm, inequilateral, pinnules sessile to adnate, infrequently stalked 1–2 mm, also inequilateral, 2–7 X 0.8–2 cm, cut 1⁄3–3⁄4 of distance to costules, narrowly to broadly cuneate proximally, more deeply lobed acroscopically than basiscopically, segment margins dentate; indument essentially absent on both surfaces, or adaxially of sparse minute papillae 0.05 mm in costal grooves, abaxially sometimes with sparse brown, septate hairs to ca. 1 mm long; veins free, mostly 5–8 pairs per segment, forked; sori pinnate, on the anterior veinlet of a forked pair, with entire to erose indusia mostly 2–4 X 0.5–0.8 mm; 2n=164 (Oax).A
Forma de vida
TerrestreA
Ejemplar revisado
Chis (Breedlove 22671, NY). Gro (Lorea 1949, FCME, IEB). Hgo (Rzedowski 27653, IEB, NY). Méx (Hinton 2768, US). Mich (Rzedowski 46052, ENCB). Mor (Lyonnet 550800002, MEXU). Oax (Mickel 4114, ENCB, UC). Pue (Arreguín 541, ARIZ, CHAPA, NY). Qro (Carranza 3851, IEB, UC; Rzedowski 46583, IEB). SLP (Pringle 3958, DS, NY, UC, US). Ver (Copeland herb. 44, UC, US).A
Elevación
150 – 2450 mA
Tipo de vegetación
Bosque de neblina/mesófilo, Selva altaA
Categoría IUCN
No incluidaB
Categoría NOM-059-SEMARNAT-2010
No incluidaC
Discusión taxonómica
Diplazium franconis is extremely variable and more or less intermediate in blade division between D. lonchophyllum (barely 2-pinnate proximally, with usually a single free acroscopic pinnule on lower pinnae) and D. donnell-smithii (3-pinnate). Diplazium franconis is distinguished from D. donnell-smithii (q.v.) by the less dissected blades and absence of numerous hair-like scales on the rachises and costae abaxially. Small fronds of D. franconis can be mistaken for unusually divided forms of D. lonchophyllum. Hybridization has probably occurred between D. franconis and D. drepanolobium in Chiapas (Smith, 1981) producing putative hybrids with misshapen spores (e.g., Breedlove 22293, 22484, DS, NY). Mickel 5368 (NY), from Oaxaca, also has malformed spores and was reported as “hexaploid” with 90 pairs and 93 univalents (Smith & Mickel, 1977), but this number is well beyond hexaploid, closer to heptaploid. The specimen is intermediate between D. franconis and D. donnell-smithii and may represent the hybrid between those two species. Mickel 1619 (NY, US), also from Oaxaca, was reported by Mickel and Beitel (1988) as D. drepanolobium X lonchophyllum, but we now see it more likely as D. franconis X lonchophyllum. This collection was reported as triploid, ca. 41II + 75I in meiosis (Mickel et al., 1966; Mickel & Beitel, 1988), but this number more closely approximates what would be expected of a tetraploid in Diplazium (2n=164). It also suggests that D. franconis and D. lonchophyllum have a genome in common. Breedlove 36649 (DS, CAS), from Chiapas, has malformed spores and might also be D. franconis X lonchophyllum. The parentage of these and other putative hybrids in this group cannot be resolved satisfactorily until further cytological and probably also isozymic studies are done.
Specimens seen from the states of Querétero, San Luis Potosí, and Hidalgo are less dissected than those in southern Mexico. Pinnules are often rounded at the tips, with crenulate margins and, sometimes, a single acroscopic shallow lobe; also, there are fewer free pinnules on the proximal pinnae.
A
Specimens seen from the states of Querétero, San Luis Potosí, and Hidalgo are less dissected than those in southern Mexico. Pinnules are often rounded at the tips, with crenulate margins and, sometimes, a single acroscopic shallow lobe; also, there are fewer free pinnules on the proximal pinnae.
A