Bulbostylis maritima Sunil, V.P. Prasad & Naveen, 2020

Sunil, Chandrasseril Narayanan, Prasad, Vadhyaruparambil Prabhakaran & Kumar, Vannaratta Naveen, 2020, Bulbostylis maritima-A new species of Cyperaceae from coastal Kerala, India, Phytotaxa 430 (1), pp. 51-56 : 52

Bulbostylis maritima Sunil, V.P. Prasad & Naveen , sp. nov. ( Figs. 1–3 )

Bulbostylis maritima is allied to B. subspinescens by its terminal head inflorescence and presence of 3 stamens, but differing by glabrous culms, large bracteoles with prominently ciliate apex, large glumes with retuse apex and prominently thick keel with knee-like swelling at base, broadly winged rachilla with prominent cavities and prominently tubercled achenes. It is also similar to B. barbata in head inflorescence and glabrous culms, but differs in having few-flowered spikelets, large glumes with retuse apex and prominently thick keel with knee-like swelling at base, broadly winged rachilla with prominent cavities, presence of 3 stamens and prominently tubercled achenes.

TYPE:— INDIA, Kerala, Ernakulam district, Munambam 10 ° 10’33.77” N, 79°9’59.00” E, 12.12.2012, C. N. Sunil & Naveen Kumar 5019 (Holotype: CAL!; Isotypes: MH!, CALI!, SNMH!) .

Annual with fibrous roots. Culms tufted, erect, slender, 6–23 cm high, 0.5–1 mm thick, obtusely trigonous, glabrous, smooth, striate when dry. Leaves basal, 3–6 on culm; lower 2 or 3 bladeless, scale-like, ovate, 4–6 × 2–3 mm, acuminate at apex; upper 1–3 laminate, 0.4–4 cm long, 0.5–1 mm wide, linear, scabrous along margins, acute to acuminate at apex; sheaths membranous, 0.8–4 cm long, scabrous along margins, ciliate at orifice. Inflorescence a terminal head of 6–22 sessile spikelets, 1–1.5 cm across, subspherical. Involucral bracts 1–4, linear, shorter or longer than the inflorescence, 5–25 × 0.4–0.6 mm, acute at apex, scabrous along margins, ciliate on the dilated membranous portion towards base. Spikelets sessile, ovoid-lanceolate, 4–7 × 1.8–2.2 mm, angular, 4–7-flowered, subtended by 1 or 2 sheath-like bracteoles. Bracteoles broadly oblong to obovate, 2.5–3.5 × 2–2.5 mm, ciliate at the truncate to emarginate or obtuse apex. Glumes spirally imbricate, oblong-lanceolate or boat-shaped, 2.8–4.5 × 1.4–1.8 mm, retuse at apex, ciliate along the margins, hispid throughout; keel thick with a knee-like swelling towards base, extending beyond the apex into a straight or curved 0.3–1.3 mm long mucro, hispid, green; 1 or 2 lowermost glumes sterile with up to 2 mm long mucro. Stamens 3; filaments 2–3 mm long, hyaline; anthers linear-oblong, 1–1.3 mm long, apiculate at apex. Ovary trigonous, obovoid, 0.45–0.7 × 0.3–0.5 mm; style 1.8–2 mm long, dilated at base; stigmas 3, 0.7–1 mm long, ciliate. Achene obtusely trigonous, broadly obovoid, 0.6–0.8 × 0.5–0.7 mm, very shortly stipitate at base, apex with persistent style base, densely tubercled, whitish to straw-coloured.

Figures

FIGURE 1. A. Habit; B. Inflorescence; C. Spikelet; D. Bracteole; E. Sterile glume; F. Glume—side view; G. Glume—adaxial view; H. Dried glume showing the knee-like projection at base; I. Rachilla with prominent cavities; J. Pistil; K.Achene; L. Magnified portion of the achene showing isodiametric cells with tubercles.

FIGURE 2. A. Habit; B. Spikelet; C. Bracteole; D. Glume—lateral view; E. Glume—adaxial view; F. Rachilla with prominent cavities; G. Flower; H. Achene.

FIGURE 3. SEM micrographs of the achenes and their magnified surface: A & B. Bulbostylis barbata; C & D. B. subspinescens; E & F. B. maritima.