Chusquea paucispiculata A.S. Vega & Rúgolo, 2014

Guerreiro, Carolina, Olivera, J. José Alegría, Rúgolo De Agrasar, Ma. E., Beck, Stephan G. & Vega, Andrea S., 2014, Two new species and synopsis of Chusquea subg. Platonia (Poaceae: Bambusoideae: Chusqueinae) in Bolivia and a new record for Peru, Phytotaxa 183 (4), pp. 224-238 : 231-232

4. Chusquea paucispiculata A.S. Vega & Rúgolo , sp. nov.

Type:— BOLIVIA. La Paz: Nor Yungas, Chuspipata 1 km hacia Cotapata , 3080 m, 22 August 1999, fl., Beck 26225 (holotype LPB!, isotypes K, SI!). Figs. 3–4 .

Chusquea paucispiculata is related to C. asymmetrica and differs from it by having s ynflorescences (50–)55–88 × 47–56 cm with basal primary branches 10–29 cm long;spikelets (3.5–)4–4.5(–5.1) × 2.5–4 mm including awns, purplish at maturity;lower glume (2–) 3– 4.5 mm long, ca. ½ or subequal to the length of the spikelet, 1-nerved, base ovate, abruptly acuminate, short awn ca. 1 mm long; upper glume (2.5–) 5–6 mm long, ca. ¾, equal or exceeding the length of the spikelet body, apex acuminate, the short awn ca. 1 mm long; fertile floret glabrous in both surfaces;anthers 1.7–2 mm long; and stigmas bearded.

Perennials 2.5–3 m tall, including the synflorescences, caespitose, growing isolated or in small colonies. Culms 0.4 cm diam., hollow, glabrous. Rhizome sympodial; cataphylls papyraceous, shining, stramineous-brownish, apex acute, with a rigid mucro, glabrous. Foliar succession between cataphylls to culm leaves gradual. Culm leaves: blade reduced to a rigid mucro. Succession between culm to foliage leaves abrupt. Foliage leaves: pseudopetiole 5–8 cm long, in subtending leaf of the synflorescence ca. 0.7 cm long, glabrous; outer ligule ca. 1 mm long, cartilaginous, glabrous; abscission zone between leaf sheath and pseudopetiole inconspicuous; inner ligule ca. 9 mm long, margin denticulate, without fimbriae, cartilaginous, decurrent to the leaf sheath, glabrous; blades (91–)150–200 × 2–3 cm, erect, narrowly lanceolate, midrib eccentric, abaxially prominent on the lower half, adaxially not tessellate, abaxially weakly tessellate, margin scabrous, apex acute, glabrous. Synflorescence (50–)55–88 × 47–56 cm, paniculate, exserted from the subtending leaf at maturity, lax, branches paucispiculate. Main axis pluricarinate, scabriusculus on the carinas. Basal primary branches 10–29 cm long. Pulvini well developed, yellow, basally at the base of the branches and pedicels, glabrous. Rachis pluricarinate, scabrous on the carinas. Pedicels 0.5 mm long, scabrous. Spikelets (3.5–)4–4.5(–5.1) × 2.5–4 mm, purplish at maturity. Glumes unequal in length. Lower glume (2–) 3–4.5 mm long, ca. ½ or subequal to the length of the spikelet, 1-nerved, midrib centric, base ovate, abruptly acuminate, short awn ca. 1 mm long, scabrous on both surfaces. Upper glume (2.5–) 5–6 mm long, ca. ¾, equal or exceeding the length of the spikelet body, 3-nerved, base ovate, apex acuminate, the short awn ca. 1 mm long., scabrous on both surfaces. Lower sterile lemma 3–3.5 mm long, 3-nerved, apex mucronate, keeled, margins with purplish tints. Upper sterile lemma 3.3–4 mm long, 3-nerved, apex mucronate, keeled, with purplish tints. Fertile floret glabrous in both surfaces. Fertile lemma 4.3–4.5 mm long, 3-nerved, navicular. Palea 4.3–4.5 mm long, 5-nerved, navicular, bimucronulate. Lodicules 3, 0.5–0.7 mm long, membranaceous, obovate, apex obtuse, crenate. Stamens 3; anthers 1.7–2 mm long, pale-yellow. Ovary glabrous; stigmas 2, bearded, pale with purplish tints, exserted. Caryopsis immature.

Geographic Distribution and Ecology: — Bolivia and Peru. In Bolivia, it occurs at 3000–3100 m in “Ceja de Monte”. In Peru, it has been considered as a common species, collected in Ceja de Monte, in a very wet and reduced elfin forest.

Additional Material Examined: — BOLIVIA. La Paz: Nor Yungas, Road La Paz-Coroico , ca. 2 km NW Chuspipata, ca. 3100 m, 16º17´S, 67º50´W, 22 August 1999, veg., J . Müller 7475 ( JE, LPB); ditto, 24 April 2000, fl., Wood 16300 ( K, LPB); 0.5 km from Cotapata to Chuspipata , ca. 3100 m, 16º17´11¨ S , 67º50´43¨ W, 25 July 2010, veg., Beck 32668 ( LPB) .

PERU. Cusco: La Convención, peak between Camps 3 & 4, ca. 2555 m, 12º37’S, 73º34’W, 3 July 1968, fl., Dudley 10686 ( USM) .

Observation:— Chusquea paucispiculata is also similar to C. tovari , which differs from the former by its wider foliage leaf blades 4–6.6 cm lat., its greater synflorescences (75–) 90–108 cm long and the palea that bears an acute apex, while in C. paucispiculata , it is bimucronulate.

The micromorphological characters of foliage leaf blades of C. parodii and C. paucispiculata are compared with those of related and sympatric species of Chusquea subg. Platonia ( C. laegaardii and C. asymmetrica ) in Tables 1–2 and Figs. 5–6 .

Figures

FIGURE 3. Chusquea paucispiculata. A. Floriferous culm. B. Foliage leaf: inner and outer ligule, detail. C. Leaf blade fragment showing midnerve in eccentric position. D. Spikelet. E. Lower glume, ventral view. F. Upper glume, ventral view. G. Upper glume, dorsal view. H. Lower sterile lemma, ventral view. I. Upper sterile lemma, ventral view. J. Fertile lemma, lateral view. K. Palea, lateral view. L. Lodicules,

FIGURE 4. Chusquea paucispiculata. A. Habit. B. Synflorescences. Scale bars = 50 cm for A, 10 cm for B. Photographs: S. Beck.

FIGURE 5. Foliage leaf blade transverse section LM micrographs. Chusquea asymmetrica. A. Keel [from Beck 17683 (SI)]. B. General view [from Beck 17683 (SI)]. C. Margin [from Clark 1113 (AAU)]. Chusquea laegaardii [from Beck 24403 (SI)]. D. Keel. E. General view. Chusquea parodii [from Beck 26221 (SI)]. F. Keel. G. General view. H. Margin. Chusquea paucispiculata [from Beck 26225 (SI)]. I. Keel. J. General view. K. Margin. Scale bars = 200 μm for D, 100 μm for all others.Abbreviations: Bc, bulliform cells; Scl, sclerenchyma; VB1, first order vascular bundle; VB2, second order vascular bundle; VB3, third order vascular bundle.

FIGURE 6. Foliage leaf blade abaxial epidermis SEM micrographs. Chusquea asymmetrica [from Clark 1113 (AAU)]. A. General view. B. Detail of furrow. Chusquea laegaardii [from Laegaard 101905B (AAU)]. C. General view. D. Detail of stomata. Chusquea parodii [from Beck 26221 (SI)]. E. General view. F. Detail of stomata. Chusquea paucispiculata [from Beck 26225 (SI)]. G. General view. H. Detail of prickle hair. Scale bars = 100 μm for C, G and H, 50 μm for A and E, 20 μm for B and D, 10 μm for F.Abbreviations: In, inflated long cell; Mi, microhair; Pa, papillae; Pr, prickle; St, stomata.