Sticherus moyobambensis J.Gonzales, 2011

Gonzales, Jasivia & Kessler, Michael, 2011, A synopsis of the Neotropical species of Sticherus (Gleicheniaceae), with descriptions of nine new species, Phytotaxa 31, pp. 1-54 : 34-36

Sticherus moyobambensis J.Gonzales , sp. nov. ( Fig. 12 )

Differt a Stichero velato segmentis distanter pectinatis angustioribusque, venis segmentarum branchibusque magis squamatis, squamis rigentibus hyalinis branchum venarumque centralium angustioribus, paginis abaxilibus segmentarum squamas destitutis.

Type: — PERU. San Martín: Zepelacho, near Moyobamba , 1100–1600 m, December 1933, Klug 3458 (holotype B!, isotypes G!, NY!, S!) .

Rhizomes unknown. Petioles 30–60 cm long and 4.0– 4.5 mm thick, light-castaneous to stramineous, weakly scaly. Rachises ca. 35 cm long between pinnae, the scales large, whitish; aphlebiae trifoliate to pinnatifid. Fiddleheads 4–7 mm in diameter, matted, the scales dense, white to yellow. Buds of proximal branches large and of distal branches shorter, ascending, semi-open, the scales narrowly lanceolate, basally shortened, apically fringed and/or long-ciliate, (1.5–)3.0–4.0(–6.5) × 0.4–0.8(–1.4) mm, bicolorous with orange bases and centers and whitish margins, the margins with straight, regularly arranged cilia 1/5–1/3 times the scale length, with lattice-like cell texture and with short, narrowly hexagonal cells and linear marginal cells. Pinnae 30–60 cm long, branches 3–4-forked, 1 st and 2 nd branches shorter than the distal ones, (5–) 6–15 cm long and 2.0– 3.5 mm thick, both branches with trifoliate aphlebiae, the 1 st branch not pectinate, 2 nd branch pectinate, ca. 4 cm wide with segments, the internal segments gradually reduced, 3 rd branch 18–34 cm long and 1.5–2.0 mm thick, 4.5–5.0 cm wide with segments, 4 th branch ca. 20 cm long and ca. 1.5 mm thick, lanceolate, 3.0– 3.5 cm wide with segments, with ca. 2.5 segment per cm, each opposite pair of branches unequal in size; adaxial scales mixed, one type linear, 2.5–5.0 × 0.8–1.2 mm, translucent to light orange, the second type rectangular, 0.4–0.5 × 0.05 mm, both scale types with rectangular-linear or irregular cells; abaxial and lateral scales lanceolate, narrow, apically with 3 long cilia, a tuft of cilia, or with the middle cilium prolonged to a pectinate hair, 0.6–1.6(–3.0) × 0.2–0.3(–0.5) mm, about 7 cell rows wide, whitish to dull translucent, the margins with long, curved cilia 1/3–1/2 times the scale length, with lattice-like cell texture and hexagonal cells. Segments linear to oval, chartaceous, (1.4–) 1.8–2.4 cm × 2.5–3.0(–3.5) mm, the margins slightly revolute, ciliate; abaxial scales only on the veins, covering 15–60% of the leaf surfaces; midvein scales fimbriate, translucent to light orange, mixed, one type linear, 2.5–3.2 × 0.1 mm, 2 cell rows wide, the margins with a few cilia about 1/3 times the scale length, the cells rectangular, very large, the second type rectangular, sometimes with a pectinate apical hair to 2.4 mm long, 0.5–0.8 × 0.3 mm, 3 to 4 cell rows wide, the cells elongate, rectangular, each bearing a marginal cilium, the third type reduced, fimbriate, ca. 0.5 × 0.1 mm, 2–4 cell rows wide, the margins with wavy cilia 3–4 times the scale length; abaxial scales restricted to the secondary veins, scattered, covering about 40% of the surfaces, arachnoid, 0.05–0.30 mm in diameter; adaxially glabrous or with a few fimbriate scales similar to, but paler than, those on the midveins. Sori medial, nested superficially within arachnoid scales, 9–16 pairs per segment, 3–5 sporangia per sorus.

Distribution and ecology: —Known only from the type locality at 1100–1600 m at Zepelacho near Moyobamba in northern Peru. We surmise that this species was collected on mountain ranges with stunted vegetation on highly nutrient-deficient sandy soils that are characteristic of this region.

Notes: — Sticherus moyobambensis is presumably related to S. velatus , as evidenced by their large size and similar scale patterns. Sticherus moyobambensis differs in having narrower and more remote segments, much more densely scaly branches and segment midveins, narrower, rigid and translucent midvein and branch scales, and by lacking scales on their abaxial segment surfaces. Unlike any other species in this complex, fiddleheads of S. moyobambensis are densely covered in orange (vs. whitish to bicolorous) scales.

Figures

FIGURE 12. Sticherus moyobambensis A. bud scales; B. abaxial branch scales; C. midvein scales. Klug 3458. Scale bars in A–C3 are all 1 mm long.