Asplenium dianae A.R. Sm.
Descripción
Ab A. myriophyllo laminis angustioribus, tantum 2-pinnatis, pinnulis (praeter pinnulam acroscopicam basalem in quoque pinna) valde adnatis, non vel vix constrictis basi, laminis chartaceis differt. (Honoring Diana (Dee) Ferguson, who has assisted with details of descriptions of Asplenium for this work, as well as descriptions of species in a few other genera.)
Roots fine, wiry, not proliferous; rhizomes erect; rhizome scales dark brown to blackish, strongly clathrate, to ca. 3 X 0.8 mm, entire; fronds clumped, 9–13 cm long; stipes brownish, dull, 1–2 cm X 0.5–0.8 mm, <1⁄5 of frond length, glabrescent or with a few hair-like or linear-lanceolate scales to ca. 4 cells wide, adaxially with narrow green wings for much of their length; blades chartaceous, lanceolate or narrowly elliptic, 2-pinnate, 8–12 X ca. 2 cm, narrowed proximally, to 6 proximal pairs gradually reduced with the lowermost pair trifid and less than 4 mm long, blade apices confluent, gradually tapered, pinnatifid, not proliferous; rachises brownish or greenish distally, dull, with sparse hair-like scales and green lateral wings 0.2–0.3 mm wide; pinnae deltate-lanceolate, to ca. 20 pairs, to 1.2 X 0.5 cm, sessile, not articulate, inequilateral, excavate at basiscopic bases, auriculate acroscopically, pinnules to 4 pairs per pinna, strongly ascending ca. 30–40° from costae, simple and undivided except for the largest basal acroscopic one, that cuneate-flabellate and 2–4-toothed at apices, to 5 mm X 2.5 mm, but mostly ca. 1–2 X 1 mm; veins ± evident on both sides of blades, simple or occasionally 1-forked, tips prominent adaxially; indument abaxially of scattered, appressed, clavate hairs 0.1 mm long; sori one per ultimate segment; indusia 1–2 X 0.5–0.6 mm, margins entire; spores reniform, probably 64 per sporangium.A
Roots fine, wiry, not proliferous; rhizomes erect; rhizome scales dark brown to blackish, strongly clathrate, to ca. 3 X 0.8 mm, entire; fronds clumped, 9–13 cm long; stipes brownish, dull, 1–2 cm X 0.5–0.8 mm, <1⁄5 of frond length, glabrescent or with a few hair-like or linear-lanceolate scales to ca. 4 cells wide, adaxially with narrow green wings for much of their length; blades chartaceous, lanceolate or narrowly elliptic, 2-pinnate, 8–12 X ca. 2 cm, narrowed proximally, to 6 proximal pairs gradually reduced with the lowermost pair trifid and less than 4 mm long, blade apices confluent, gradually tapered, pinnatifid, not proliferous; rachises brownish or greenish distally, dull, with sparse hair-like scales and green lateral wings 0.2–0.3 mm wide; pinnae deltate-lanceolate, to ca. 20 pairs, to 1.2 X 0.5 cm, sessile, not articulate, inequilateral, excavate at basiscopic bases, auriculate acroscopically, pinnules to 4 pairs per pinna, strongly ascending ca. 30–40° from costae, simple and undivided except for the largest basal acroscopic one, that cuneate-flabellate and 2–4-toothed at apices, to 5 mm X 2.5 mm, but mostly ca. 1–2 X 1 mm; veins ± evident on both sides of blades, simple or occasionally 1-forked, tips prominent adaxially; indument abaxially of scattered, appressed, clavate hairs 0.1 mm long; sori one per ultimate segment; indusia 1–2 X 0.5–0.6 mm, margins entire; spores reniform, probably 64 per sporangium.A
Ejemplar revisado
Known only from the type. Tam(F. & M. Webster 221, TEX).A
Distribución
México (país) EndémicoA
Elevación
500 mA
Categoría IUCN
No incluidaB
Categoría NOM-059-SEMARNAT-2010
No incluidaC
Discusión taxonómica
Of Mexican species, this is most similar to A. myriophyllum.
It differs from that in the narrower, less divided blades (only 2-pinnate); strongly adnate pinnules (except the basal acroscopic one of each pinna), not or only slightly constricted at the bases; and chartaceous (vs. thin-herbaceous) blades. The spores are reniform and normal in appearance; although in the type specimen most sporangia have shed their spores, some were found with at least 45 spores, indicating that this species is probably sexual, with 64 spores per sporangium.
The closest relative of A. dianae may be A. sciadophilum Proctor, endemic to Jamaica. That species, although basically 2-pinnate like A. dianae, has larger fronds (20–40 X 5.5 cm) and much longer stipes (4–11 cm), and is, like A. myriophyllum, thintextured; it also has lighter green blades than A. dianae. Additional relatives, all apparently less closely related, include several species mentioned by Adams (in Davidse et al., 1995) under A. cladolepton Fée, i.e., A. barclayanum C. D. Adams from Isla del Coco, A. macraei Hook. & Grev., from Hawaii, and A. haenkeanum (C. Presl) Hieron., from Colombia to Peru (Tryon & Stolze, 1993).
The type was regrettably mounted abaxial side down with nearly indestructable glue, causing many of the important characters to be obscured. Surgery on the specimen revealed that all of the half dozen developed fronds are fully fertile.A
It differs from that in the narrower, less divided blades (only 2-pinnate); strongly adnate pinnules (except the basal acroscopic one of each pinna), not or only slightly constricted at the bases; and chartaceous (vs. thin-herbaceous) blades. The spores are reniform and normal in appearance; although in the type specimen most sporangia have shed their spores, some were found with at least 45 spores, indicating that this species is probably sexual, with 64 spores per sporangium.
The closest relative of A. dianae may be A. sciadophilum Proctor, endemic to Jamaica. That species, although basically 2-pinnate like A. dianae, has larger fronds (20–40 X 5.5 cm) and much longer stipes (4–11 cm), and is, like A. myriophyllum, thintextured; it also has lighter green blades than A. dianae. Additional relatives, all apparently less closely related, include several species mentioned by Adams (in Davidse et al., 1995) under A. cladolepton Fée, i.e., A. barclayanum C. D. Adams from Isla del Coco, A. macraei Hook. & Grev., from Hawaii, and A. haenkeanum (C. Presl) Hieron., from Colombia to Peru (Tryon & Stolze, 1993).
The type was regrettably mounted abaxial side down with nearly indestructable glue, causing many of the important characters to be obscured. Surgery on the specimen revealed that all of the half dozen developed fronds are fully fertile.A