Racinaea graminispicula Gouda, 2025

Gouda, Eric J., 2025, Two new species with tiny flowers for the genus Racinaea (Bromeliaceae), Phytotaxa 682 (3), pp. 267-273 : 270-272

Racinaea graminispicula Gouda spec. nov. Figure 3 A–H , 4 .

Type:— Peru, San Martin, N. E. of Moyobamba, 1000 to 1500 m. elev., ca 2009 J. Kent s.n., fl. cult. in collection E. J. Gouda with number EG-1216 ( U).

Diagnosis:—A Racinaea pugiformis like species, but the spikes are more robust and clustered suberect ( vs. laxly divergent to spreading), floral bracts even, broadly obovate, rounded, 2.7 mm long, much exceeded by the sepals, green at anthesis ( vs. distinctly nerved, ovate, acute, 4–5 mm long, equaling the sepals, often stramineous and dry at anthesis), sepals 3 x 2.3 mm, emarginate ( vs. 4–5 x 3 mm, rounded-apiculate), petals erect, not exceeding the sepals ( vs. petal blades spreading to recurving and exceeding the sepals).

Plant flowering 40–70 cm tall, acaulescent, with ca 12 leaves, forming a funnelform rosette, green. Leaves spirally arranged, 18–22 cm long, much shorter than the inflorescence, but exceeding the peduncle; sheath large, contrasting with the blade in color, merging into the blade, thin coriaceous at the base to chartaceous upward, elliptic, slightly inflated, 7–8 cm long, 4.5–5 cm wide, with narrow membranaceous margins, densely lepidote on both sides with closely appressed dark centered trichomes, adaxially dark purple-red in the upper half to pale brown toward the base and abaxially; blade suberect to arching, soft, chartaceous to thin coriaceous, nearly flat, sub-ligulate to narrowly strap-shaped, 10–12 cm long, ca 2 cm wide, with slightly undulate margins, apex attenuately acute or narrowly acuminate, sparsely to subdensely lepidote on both sides with minute transparent trichomes not masking the color of the blade, green. Inflorescence erect, twice-branched or rarely thrice-branched of a few short spikes, with ca 10 slightly spirally arranged primary branches (ca 20 spikes in total), fertile part 20–48 cm long, to 12 cm wide (diameter), lax, but the spikes sub-densely clustered, fertile part paniculate, sparsely to subdensely lepidote in some parts, not masking the green coloration; peduncle short, wholly covered by bracts except at the distal end, erect, stout, 11–18 cm long, 2.2–3.5 mm in diam., sub-densely lepidote to glabrescent, exceeding the leaves, green, even; peduncle bracts erect and clasping the peduncle, not foliaceous, slightly to densely imbricate, about twice as long as the internodes or less, chartaceous, narrowly oblong, fleshy acuminate at the apex, abaxially subdensely lepidote, green; main axis (rachis) elongate, slender, slightly flexuous, terete, sparsely lepidote, but soon glabrescent, green, internodes 2–2.5 cm long in the lower part, becoming shorter upwards; primary bracts divergent to spreading with the branches, remote, chartaceous, like the upper peduncle-bracts but slightly shorter and upwards decreasing in size, with broad hyaline margins, apiculate, exceeding the stipes of the branches. Spikes erect or slightly divergent and ascending, laxly distichously (4–)10–18 flowered, complanate, linear-oblong, (2–) 5–7.5 cm long, 0.3 cm wide, with one or a few sterile flowers at the base and the apex; stipes short to prominent, the lower with a few bracts, not bracteate upwards, spreading to a right angle with the axis, but ascending and appearing divergent, the lower ones slender, 0.3–3.3 cm long; stipe bracts erect (contiguous with the stipe), remote; rachis wholly exposed, slender, flexuous, slightly excavated near the flowers, sparsely to densely lepidote of slightly spreading trichomes, green, the internodes 2.3–3 mm long. Floral bracts erect, remote, chartaceous, even, ecarinate, broadly obovate, rounded, incurved, 2.7 mm long, 2.7 mm wide, much exceeded by the sepals, slightly exceeding the internodes, with broad hyaline margins, abaxially sparsely lepidote at the base only, green. Flowers 4–4.5 mm long, contiguous with the rachis (suberect); receptacle (flower base) obconic, short ( 0.5 mm); sepals chartaceous, surface even, slightly asymmetrical, obovate, emarginate, incurved, 3 mm long, 2.3 mm wide, with broad hyaline margins, adaxial and abaxial ones all alike, free, glabrous, green; petals slightly fleshy, 3 mm long, 1.5 mm wide, erect, not exceeding the sepals, ovate or elliptic, rounded or obtuse, free from each other, white. Stamens included, all equal in length, 2 mm long, exceeding the pistil; filaments free, lanceolate, white; anthers dorsifixed at about one third from base, short, bi-lobed at the base, apiculate at the apex, green. Pistil exceeded by the stamens, 1.8 mm long; ovary globose, ca 1 mm long, rounded and then tapering into the style, green; style shorter than the ovary; stigma short conduplicate, erect, papillose.

Distribution and habitat:—Epiphyte in dry forest, only known from the type locality, at 1000 to 1500 m. elevation.

Etymology:—The epithet is referring to the grass (‘Gramen’) like spikelets (‘Spicula’).

Observations:—This new species is morphologically closely related to Racinaea pugiformis ( Smith 1930: 13) Spencer & Smith (1993: 156) , but the leaves are subligulate, suberect, lustrous bright green ( vs. narrowly triangular, curved divergent, cinereous-green), the peduncle short and hidden in the rosette ( vs. elongate, about twice the length of the leaves); inflorescence with the primary branches spreading, then curved ascending and the spikes clustered suberect closely together ( vs. the primary branches spreading and then the spikes divergent to spreading, not clustered), the spikes short stipitate or subsessile (except the terminal one) ( vs. long and slenderly stipitate), all flower parts smaller (see diagnose).

Figures

FIGURE 3. Racinaea graminispicula Gouda, A. primary bract; B. apical part of a spike; C. flower with floral bract; D. floral bract; E. sepals; F. petals; G. stamens and pistil; H. stamens and pistil in detail; drawing of a fresh flower from the type specimen, by the author.

FIGURE 4. Racinaea graminispicula Gouda, A. Habit of flowering plant in cultivation by the author; B. inflorescence showing the spirally arranged primary branching; C. primary branches with the ascending densely inserted spikes; D. spike and flower in detail, note the petals not exceeding the sepals. All photos by the author.