Terpsichore diaphana Moguel & M.Kessler, 2009

Velázquez, Ana Laura Moguel & Kessler, Michael, 2009, Taxonomic notes on the fern species group around Terpsichore lanigera (Polypodiaceae), including the descriptions of three new species and one new variety, Phytotaxa 2, pp. 35-45 : 38-40

Terpsichore diaphana Moguel & M.Kessler , sp. nov. ( Fig. 2 ).

Plantae epiphyticae, epillithicae aut terrestres cum indumento setarum pilorumque parvorum pallido; pinnae lineareoblongae vel lineare-deltatae, cum hydathodis adaxialiter numquam exudatis calcareis ferentibus, apice obtusae vel acutae, marginibus et paginis abaxialibus dense setuliferis; setae stellatae, usque 10-ramificatae.

Type:— BOLIVIA: La Paz: Nor Yungas, hill above Cotapata on La Paz-Caranavi road, 16°17’S, 67°50’W, 3200 m, 15 Aug 1990, A. & L. Fay 3031 (holotype, LPB!; isotypes, LPB!, MO!, NY!, UC!) .

Plants epiphytic, saxicolous or terrestrial; rhizomes 0.5–3.0 cm long, short-creeping to suberect, radially symmetric, scaly, the scales castaneous, concolorous, dull, 0.5–2.0 mm long, setulate and usually also puberulent, the setae present on the margins and sometimes on the surfaces, hyaline, 0.2–0.5 mm long, usually not much longer than the scale breadth, the hairs present at the scales margins and apices, scarce to abundant, 0.05–0.10 mm, branched, bearing an orangish, oval, apical cell on one of their shorter rays; fronds 15–60 × 1.5–6 cm, caespitose, pendulous, with indeterminate growth; stipes 0.2–0.4 mm × 0.5–1.5 cm, castaneous to dark brown, with simple, hyaline to yellowish, 0.5–2.0 mm long setae and hyaline to yellowish, simple or branched, 0.1–0.2 mm long hairs each with an orangish, oval, apical cell on a shorter ray; blades linearlanceolate, pinnatisect, thin-chartaceous, gradually tapering at the apices and very gradually tapering at the bases, with up to 15 reduced segment pairs at the bases (1/3 to 1/2 of the frond) and often also with a few reduced segments at the apices or elsewhere in the blades (seasonal constrictions); rachises sclerenchymatous, dark brown, puberulent like the stipes and with abundant, hyaline to golden, 0.3–2.0 mm long setae, these simple and abaxially also bifurcate and stellate, 3–10-branched (sometimes with one or more rays hair-like with colored, oval, apical cells), occasionally these setae very thin and matted (in extreme cases almost arachnoid); pinnae perpendicular or irregularly up to a 60° angle oblique to the rachises, alternate, 0.3–0.6 × 1.0– 3.5 cm, linear-deltate to linear with parallel margins, sometimes reflexed, 1/3 of their width to entirely adnate to the rachises, symmetric to slightly asymmetric at the bases, excised to slightly curved acroscopically and slightly curved to slightly decurrent basiscopically, sometimes the entire bases slightly dilated, apices obtuse to subacute, margins entire, sometimes slightly sinuate, densely setose, the setae bifurcate and basally stellate, 3–10-branched, yellowish to golden, 0.3–0.5(–2.0) mm long; sinuses 2–6 mm wide; veins free, 1- furcate, ending medially, the costae conspicuous adaxially and abaxially, dark brown to black; blade surfaces puberulent like the stipes, also adaxially and abaxially with simple, bifurcate and 3–10-branched, hyaline to golden, 0.3–0.5(–1.0) mm long setae, occasionally these setae abaxially very thin and matted (in extreme cases arachnoid); hydathodes inconspicuous, lime dots lacking; sori pale yellowish to pale orangish, round, arising at the vein apices, up to 30 per pinna, sometimes only on the apical halves of the pinnae; receptacles not or sparely setose; sporangia ciliate, the cilia ca. 0.3–1.5 mm long. Spores elongated tetrahedral-globose, ca. 33 × 37 µm, trilete.

Distribution and ecology:— Peru (Ayacucho) and Bolivia (Cochabamba, La Paz), in Polylepis forests and the humid montane Yungas forests of the Bolivian Andes from 2400 m to 4000 m. Found in shady, humid places, as an epiphyte or saxicolous, on tree trunks, gorges, rocky cliffs, and shallow caves, frequently deeply buried in moss and perhaps for this reason with numerous reduced basal segments.

Etymology:—In Latin diaphanus means colourless and nearly or quite transparent, and refers in this case to the pale indument of these plants.

Specimens examined (paratypes):— PERU: Ayacucho: Huamanga, Ayacucho-Andahuaylas, km 200, above Ocro, Lehnert 337 ( GOET) . BOLIVIA: Cochabamba: Prov. Ayopaya, 2 km SE of Saila Pata, Kessler 12450 and 12479 ( UC) ; Prov. Ayopaya, km 10 Cocapata to Cotacajes, Kessler 9364 ( GOET) ; Prov. Ayopaya, near community Pampa Grande, Jiménez & Moguel 1664 ( GOET) ; Prov. Chapare, new road to Santa Cruz, Jiménez & Moguel 1733, 1739 and 1741 ( GOET) , Jiménez & Moguel 1734, 1740 and 1751 ( LPB) ; Prov. J. Carrasco T., 3 km from Siberia to Karahuasi, Kessler 9148 ( LPB, UC) . La Paz: Gran Poder, small gold mine about 40 km N of Sorata, Brooke 6472 (NY); Parque Nacional Cotapata, Bach 1830 ( GOET) , Kessler 11715 ( GOET) ; Parque Nacional Madidi, Jiménez 1091 ( LPB) ; Prov. Inquisivi, Cerro Kharrata SSE Camillaya, J. Müller & J. Heinrichs 6426 ( GOET, LPB) ; Prov. Inquisivi, Choquetanga community (serranías de Lulini), Salinas 2661 and 2662 ( LPB) ; Prov. J. B. Saavedra, km 15 Charazani-Chullina, Kessler 10596 ( GOET) ; Prov. Nor Yungas, near the gas station of Cotapata, A. Fay & L. Fay 2956 ( LPB) ; Prov. Nor Yungas, about 30 km after the summit to Unduavi, Beck 2845 ( LPB) ; Prov. Nor Yungas, cerro Hornuni, Jiménez & Quisbert 49 ( UC) ; Prov. Nor Yungas, near Coscapa, Jiménez 565, and 566 ( GOET) , Jiménez & Vidaurre 553 ( GOET, UC) , Moguel & Lehnert 22 ( LPB) , Moguel & Lehnert 23-32 ( GOET) ; Prov. Nor Yungas, Cotapata, A. Fay & L. Fay 2597 ( LPB) ; Prov. Nor Yungas, near Chuspipata, Moguel & Lehnert 18 ( GOET) ; Prov. Sud Yungas, Unduavi, Buchtien 2752 ( UC, US) , Gonzáles et al. 1542 and 1553 ( UC) ; road of Zongo valley , A. Fay & L. Fay 2919 ( LPB) ; Pongo, Tate 124 (NY).

Terpsichore diaphana is characterised by its pale, dense indument of setae which are strongly branched on the blade margins, blade surfaces, and rachises, by lacking lime dots on the hydathodes, by having basally many reduced segments, and by its peculiar scale and rachis hairs with orangish, oval, apical cells (which are otherwise only found on the rhizome scales of the closely related species T. contacta ). Terpsichore diaphana can be distinguished from T. smithii Rojas (2008: 15) , T. contacta , T. cultrata (Bory ex Willdenow, 1810: 187) Smith (1993: 486) and T. laxa ( Presl, 1825: 23) Smith (1993: 487) by the abundant stellate, hyaline to yellowish setae on the abaxial blade surfaces, and especially by the strongly branched, hyaline to golden, basally stellate setae of the blade margins.

Figures

FIGURE 2. Terpsichore diaphana (Moguel 23); A, habit; B, rhizome scale; C, detail of rhizome scale with hairs; D, stellate rachis seta; E, rachis hair.