Asplenium (sect. Hymenasplenium) basiscopicum, a new species from Bolivia ROBBIN C. MORAN
AND
MICHAEL A. SUNDUE
Moran, Robbin C. & Michael A. Sundue (The New York Botanical Garden, Bronx, NY 10458-5126, U.S.A.; e-mail:
[email protected] and msundue@ nybg.org). Asplenium (sect. Hymenasplenium) basiscopicum, a new species from Bolivia. Brittonia 56: 124–127. 2004.—Asplenium basiscopicum is described, illustrated, and compared to the most similar species, A. purpurascens. Key words: new species.
Asplenium, Aspleniaceae, Bolivia, Hymenasplenium, Neotropics,
While identifying fern specimens for the Flora de la Regio´n del Parque Nacional Amboro´, Bolivia (M. Nee, in prep.), we found a new species of Asplenium sect. Hymenasplenium, which we describe as follows: Asplenium basiscopicum R. C. Moran & M. A. Sundue, sp. nov. (Fig. 1). TYPE: BOLIVIA. Santa Cruz: Prov. Ichilo, Parque Nacional Amboro´, steep slopes above and 1 km S of Rı´o Saguayo, 178419S, 638449W, 750 m, 20 Jan 1988, M. Nee 36020 (HOLOTYPE: NY; ISOTYPES: LPB— n.v., MO—n.v.). Rhizomata repentia; petioli castanei; laminae pinnato-pinnatifidae; pinnae basales a latere basiscopico elongatae, pinnulis basalibus basiscopicis 2–3-plo longioribus quam pinnulis supra eas; venae liberae.
Plants terrestrial; roots 0.3–0.7 mm diam.; rhizomes 2.5–4 mm wide, creeping, the apex scaly; scales 1.9–3 3 0.3–0.5 mm, lanceolate, dark brown, clathrate, the lumina clear, faintly iridescent, the margins sparingly denticulate; fronds distichous; petiole bases 1.4–3 mm diam., swollen, persistent, 3–4 mm distant from each other on the same row; petioles 5–15 3 (0.07–) 0.1–0.2 cm, ⅓–½ the length of the frond, atropurpureous, shining, nearly glabrous, with scattered minute hairs 0.1–0.2 mm long, the base with a few scattered scales; laminae 11–25 3 8–18 cm, medium green,
herbaceous, 1-pinnate-pinnatifid, deltate to ovate-deltate, widest at the base or just above it, with (10–)14–18 pinna pairs, the apices attenuate, pinnatifid; rachises adaxially grooved, alate, the wings green, herbaceous, perpendicular to the rachis; medial pinnae 4–10 3 1–2.5 cm, lanceolate, the basiscopic side excavate for 1⁄10 – 1⁄6; the length of the pinna, the acroscopic side usually with a basal auricle, this sometimes lacking, the segment lobes incised ¼ to ⅔ of the way to the pinna costae, the pinna apices long-attenuate, the proximal pinnae short-stipitate; basal pinnae (4–)6–11 3 2– 4 cm, the basiscopic segment lobes elongate, 2–3 times longer than the lobe on the acroscopic side, the basal lobes deeply incised to within 1 mm of the pinna costa, the margins of the segment lobes crenate; veins forked 4–8 times per segment lobe; sori 3– 5 mm long, occasionally diplazioid; indusia pale, thin, the margins subentire to erose. Annular cells 17–21. Spores well formed. Distribution. Bolivia, also expected to occur in southern Peru. Tropical evergreen wet forests on the eastern slopes of the Andes, 430–1850 m. Asplenium basiscopicum belongs to sect. Hymenasplenium, a section that is sister group to the rest of Asplenium (Murakami, 1995). Its membership in the section is based on its creeping dorsiventral rhizomes, leaves in two ranks on the dorsolateral surfaces of the rhizomes, and characteristic ra-
Brittonia, 56(2), 2004, pp. 124–127. q 2004, by The New York Botanical Garden Press, Bronx, NY 10458-5126 U.S.A.
ISSUED: 7 April 2004
2004]
MORAN & SUNDUE: ASPLENIUM BASISCOPICUM
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FIG. 1. Asplenium basiscopicum. (A, B, E, Williams 1080, NY; C, D, F, Nee 36020, NY; G–I, Williams 1104, NY.)
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FIG. 2. Asplenium purpurascens. (A, Camp E-3785, NY; B, Sodiro s.n., NY; C, D, Cazalet & Pennington 5224, NY; E, Cazalet & Pennington 5199, NY.)
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MORAN & SUNDUE: ASPLENIUM BASISCOPICUM
COMPARISON
OF
TABLE I Asplenium basiscopicum
Diameter of roots (mm) Diameter of rhizomes (mm) Length of rhizome scales (mm) Diameter of petiole bases (mm) Diameter of petioles at mid-petiole (mm) Length of laminae (cm) Basiscopic pinnules of basal pinnae Length of medial pinnae (cm) Number of pinnae Number of vein forks per lobe Length of sori (mm)
chis-costae architecture as described by Murakami and Moran (1993). Within the section it differs from all other species by elongate basiscopic lobes of the basal pinnae, which are typically two to three times as long as the lobes on the acroscopic side. We name this new species A. basiscopicum to draw attention to this distinguishing characteristic. Asplenium basiscopicum most closely resembles A. purpurascens Mett. ex Kuhn (Fig. 2) by its regularly pinnatifid pinnae— a character that is unique within sect. Hymenasplenium to these two species. The two species, however, differ in several characters (Table I). A strong tendency between the two species is that the laminae of A. basiscopicum are thinner. Smith et al. (1999), who cited the holotype and the two Williams collections cited below as ‘‘Asplenium purpurascens Mett. ex Kuhn, vel aff.,’’ noted that the laminae were thinner compared to A. purpurascens (they also pointed out the unusual basiscopically elongated basal pinnae). The holotype, however, has laminae as thick as those of A. purpurascens, showing that the difference is not constant. Nevertheless, most of the specimens of A. basiscopicum have thinner laminae compared to A. purpurascens. Besides the morphological differences, the ranges of the two species do not overlap. Asplenium purpurascens occurs pri-
AND
A. purpurascens
A. basiscopicum
A. purpurascens
0.3–0.7 2.5–4 1.9–3 1.4–3 1–2 11–25 Elongate 4–10 (10–)14–18 4–8 3–5
1.5–2 4.2–6.5 1.6–2.3 2–5 1.5–2 20–30 Excavate or not elongate 6.5–12 8–11 3–4 4–8
marily on the western side of the Andes in Ecuador (Murakami & Moran, 1993), whereas A. basiscopicum occurs on the eastern side of the Andes in Bolivia. Neither species has yet been recorded from Peru, but it seems likely that A. purpurascens is likely to be found in northern Peru and A. basiscopicum in southern Peru. In the specimens cited below, the geographical coordinates for the R. S. Williams collections were obtained from Dorr (1991). Additional specimens examined. BOLIVIA. Beni: Prov. Gral. Ballivia´n, 12 km por el camino maderero, al SW del Km 12 Yucumo-Rurrenabaque, 158049S, 678079W, 450 m, 25 Jul 1997, Kessler 10819 (LPB– n.v., UC); 26 Jul 1997, Kessler 10844 (LPB–n.v., UC). La Paz: Prov. Iturralde, San Buena Ventura, [approx. 148289S, 678359W], opposite Rurrenabaque, 148289S, 678349W, ca 430 m, 12 Nov 1901, R. S. Williams 1080 (NY); Prov. Franz Tamayo, near Inglis-Inglis, ca. 9 km SE of Ate´n, 148579S, 688199W, 1850 m, 15 Aug 1902, R. S. Williams 1104 (NY).
Literature Cited Dorr, L. J. 1991. The vascular plant collections of R. S. Williams from Bolivia and Peru (1901–1902). Brittonia 43: 211–239. Murakami, N. 1995. Systematics and evolutionary biology of the fern genus Hymenasplenium (Aspleniaceae). J. Pl. Res. 108: 257–268. ——— & R. C. Moran. 1993. Monograph of the neotropical species of Asplenium sect. Hymenasplenium (Aspleniaceae). Ann. Missouri Bot. Gard. 80: 1–38. Smith, A. R., M. Kessler & J. Gonzales. 1999. New records of pteridophytes from Bolivia. Amer. Fern J. 89: 244–266.
