Dicksonia karsteniana var. spruceana (Kuhn) Lehnert, 2018

Noben, Sarah, Kessler, Michael, Weigand, Anna, Tejedor, Adrian, Rodr´, Wilson D., Gallego, Luis Fernando Giraldo & Lehnert, Marcus, 2018, A Taxonomic and Biogeographic Reappraisal of the Genus Dicksonia (Dicksoniaceae) in the Neotropics, Systematic Botany (Basel, Switzerland) 43 (4), pp. 839-857 : 850-851

1.3. Dicksonia karsteniana var. spruceana (Kuhn) Lehnert , comb. et stat. nov.

Dicksonia spruceana Kuhn , Linnaea 36: 153. 1869.

TYPE: PERU. San Martin: Near Tarapoto, Mte. Campana, [ca. 06°07’S, 76°40’W] 1855–1856, R. Spruce 472 8 (lectotype B!, inadvertently designated by Tryon 1989: 105, isolectoypes A-00020971 [image], BM-000586133 !/- 000097860 !, GH-00020972 !, K-000006839 !/– 00006840 !/– 00006841 !, LD-1763634 !/- 1763698 ![image], P-01414987 ![image]).

Trunks to 4(–6) m tall, skirt of dead fronds weakly developed; petioles with dark reddish brown setiform hairs well developed, paler (white or orange) woolly undercoat weakly developed; hairs adaxially on frond axes dark red-brown to blackish, antrorsely curved, ± appressed, petioles and lower rachises abaxially covered with matted white hairs when young, soon glabrescent, no remnants of cobwebby hairs in the axils, upper rachises, costae, costules, and midvein abaxially with few to many spreading hairs, reddish, soft, to 3 mm long, leaving a smooth to faintly scabrous surface when abraded, sparse to absent elsewhere; sori ± 1.5 mm diam. Figures 1H , 5C .

Distribution and Habitat —Found on the eastern Andean slopes of Ecuador and Peru, expected farther north ( Colombia) and south ( Bolivia). Present in lower mountain rainforests at (1400–) 1800–2000 m, usually in small numbers under a dense canopy, in deep ravines or sinkholes that are notably cooler than the surroundings ( Fig. 6 ).

Additional Specimens Examined — Ecuador.— ZAMORA-CHINCHIPE: Estación Cientifica San Francisco, 03°58’S, 79°04’W, 1820 m, Sep 2008, N. Cumbicus, J. Homeier, E. Jaramillo, B. Medina 4113 ( STU), 5 Oct 2003, M. Lehnert 957 ( GOET, UC), 2000–2010 m, 21 Sep 2010, M. Lehnert 1877 ( QCA, STU). Peru. — HUÁNUCO: SW slope of the R´ıo Llullapichis watershed, on the ascent of Cerros del Sira, shallow valley just beyond Camp 4 (Peligroso), 09°25’S 074°44’W, 1540 m 25 Jul 1969, T.R. Dudley 13254 ( MO). — SAN MARTIN: Huallaga, Saposa , alrededores de la Canaan , 2000 m, 28 Aug 2001, V. Quipuscoa, M. V´ılchez T., D. Anazco ~ B2630 ( UC).

Figures

FIG. 1. Important characters of Andean Dicksonia in the field. A–C. Trunk and leaf arrangement of plants growing outside the forest. A. Dicksonia lehnertiana, short trunks ca. 0.8 m tall, no skirt of old fronds (Anori, Dept. Antioquia, Colombia). B. Dicksonia karsteniana var. arachneosa, trunks ca. 1.7 m tall, with skirt of old fronds (La Cocha, Dept. Nar~ no, Colombia). C. Dicksonia stuebelii, trunks 2–3.6 m tall, fronds characteristically erect, dead fronds persisting but not forming skirt (Colan, Dept.Amazonas, Peru).D–I. Hairs on petioles.D.Spreading bristly hairs, D.lehnertiana (Yarumal, Dept.Antioquia, Colombia). E. Matted hairs, paler undercoat exposed by emerging adventitious buds, D. navarrensis (Dept. Caldas, Colombia). F. Thick white undercoat with longer darker hairs emerging, D. karsteniana var. arachneosa (La Cocha, Dept. Nari~ no, Colombia). G. Woolly hairs, left D. karsteniana var. arachneosa (or probable hybrid) with D. stuebelii, right (Molinopampa, Prov. Amazonas, Peru). H. Spreading soft hairs, undercoat weakly developed to absent, D. karsteniana var. spruceana. I–J. Adventitious buds I. Buds with small coiled-up croziers (dashed circles), at base of rotting petiole still attached to trunk (right), D. navarrensis (Colombia). J. Small plant from such a bud growing in root mantle of mother plant, D. navarrensis (Panama). All pictures © M. Lehnert except for C, © A. Tejedor.

FIG. 5. Important characters of Neotropical Dicksonia. A. Dicksonia karsteniana var. karsteniana. (A1 from Lehnert 1000, GOET; A2, A4 from Mostacero and Castillo 275, UC, from locus classicus of the species; A3 from Delascio-Ch. 9063, UC). B. Dicksonia karsteniana var. arachneosa. (B1, B4 from Lehnert 2323, STU; B2 from Cumbicus et al. 457, STU). C. Dicksonia karsteniana var. spruceana. (C1, C2 from lectotype, Spruce 4728, K; C3, C4 from Quipuscoa et al. 2630, UC). D. Dicksonia navarrensis.(D1–D4 from Lehnert 3493 with Tejedor, BONN). A1–D1. Petioles, showing lower parts, either with spreading hairs (A1–C1) and varying undercoat (well developed in B1), or all hairs matted (D1). Lowest pinnae tapering, often reaching down to petiole base (A1), may be substituted for adventitious buds (D1). A2–D2. Pinnules, adaxially (not shown for B).Large ones (A2, D2) showing typical form with slightly asymmetric base, which may be more notable in smaller pinnules from pinna apex (C2). A3–D3. Sterile segments, abaxially. A4–D4. Fertile segments, abaxially.

FIG.6. Distribution of Dicksonia in South America. A. Dicksonia karsteniana (squares), D.sellowiana (dots). Inset: varieties of D. karsteniana, var. arachenosa (triangles), var. spruceana (asterisks). B. Dicksonia lehnertiana (crossed circle), D. navarrensis (triangles), D. stuebelii (stars; occurrence in northern Colombia).