PHILODENDRON DARDANIANUM
PROTOLOGUE: Philodendron dardanianum , published in Kew Bulletin 46: 648 (1991).
Philodendron dardanianum Mayo sp. nov. Philodendron brasiliensi Engler affinis sed stylo quam ovarium longiore, infundibulo styli in ovarium penetranti, stylo sine lobo centrali tholiformi, staminodiis crassioribus, squamulis intravaginalibus caulis carentibus, lamina folii angustiore lanceolato-sagittata differt. Typus: Brazil, Harley et al. 21963 (holotypus CEPEC! isotypi K! MO! US!).
SYNONYMS:
HOMOTYPIC SYNONYMS: Thaumatophyllum dardanianum (Mayo) Sakur., Calazans & Mayo
DISTRIBUTION: Brazil (Bahia, Goiás): Brazil Northeast, Brazil West-Central.
SPECIES DESCRIPTION:
Stem: decumbent, to 1 m tall, up to about 4.5 cm in diam., internodes 0.5–9 mm long; prophyll scars 4–8 mm long; intravaginal squamules lacking; foliage leaf scars obliquely and transversely elliptic, 2 cm long, 3 cm wide. Leaf: prophyll c. 23 cm long; petiole 36–46 cm long, 0.6–0.7 cm diam. at apex, sheath 9–11 cm long; leaf blade elongate-sagittate, coriaceous, yellow-green, margins entire, sometimes repand, overall length 39–46 cm long, overall width 16–21 cm; anterior division 30–35 cm long, 16–21 cm wide, apex acute to subacute, primary lateral veins 5–7 per side, arising at an angle of 40–75° to midrib, paler than blade on upper surface; posterior divisions 8–10 cm long, 0.2 × overall blade length, 9–10 cm wide, basal ribs denuded for 2.5–3.5 cm, tip obtuse to rounded, primary acroscopic veins 1–2, primary basiscopic veins lacking.
INFLORESCENCE:
Inflorescence: peduncle (8.5–)15.5–21 cm long, 1–2 cm diam. at apex; spathe (11–)12.5–16.5 cm long, (1.3–)1.5–3 cm diam., decurrent for 2–3.5 cm, outer surface green to pale green; spadix 10–12.5 cm long, fertile male zone 2.8–3.5 cm long, 1.3–1.4 cm diam., ellipsoid, thicker than upper part of sterile zone, sterile male zone 5–5.5 cm long, 1.2–1.4(–1.8) cm diam., subcylindric, thicker at base, female zone 2.5–3 cm long, 1.1–1.5 cm diam. Flowers: stamens 4 mm long, 1.1–1.4 mm diam. at apex; staminodes 3.3–3.8 mm long, 1.9–2.5 mm diam. at apex, shortly and squatly clavate, tapering strongly to base, prismatic, apex ± truncate; gynoecium 6–6.5 mm long, ± flask-shaped, ovary 2–3 mm long, 2.5–3 mm diam., ± ventricose, broader than style, locules 4–6, ovules 2–3 per locule, inserted in cluster towards locule base, style longer than ovary, c. 4 mm long, compitum very long, penetrating ovary axis usually as far as the upper third but sometimes to halfway down, ridged along its length, raphide cells concentrated around lower half, style crown distinctly lobed, tannin cells only sparsely present in style lobes, central dome lacking, stylar canals short, entering locules about halfway down, stigma 3.5–4 mm diam., covering style lobes, ± lacking tannin hairs. Fruit: not seen.
ECOLOGY:
Found in riverine marshes or among rocks, river margins in cerrado; alt. 580–800 m.
ETYMOLOGY:
Named in honor of Professor Dárdano de Andrade Lima, in memory of his great contribution to Brazilian botany, especially of the northeastern region of the country. The Latinized epithet dardanianum means “of Dárdano.”
NOTES:
1. Related to Philodendron brasiliense Engler, but differs in having the style longer than the ovary, the funnel of the style penetrating the ovary, the style lacking a central dome-shaped lobe, thicker staminodes, no intravaginal squamules on the stem, and a narrower, lanceolate-sagittate leaf blade.
2. Philodendron dardanianum has its affinities with Philodendron uliginosum and Philodendron brasiliense, but the leaf blade is relatively longer than broad and the style is greatly elongated. Indeed, the gynoecium resembles that of Philodendron williamsii except for the lack of a central dome. Other diagnostic features are the short, thick staminodes, the absence of intravaginal squamules on mature stems, and the long, narrow leaves in which the posterior divisions have only a weakly developed area of lamina on the basiscopic side.
3. So far, this species is known only from the watershed separating the drainage of the Rio São Francisco from that of the Amazon Basin, which forms the border between Bahia and Goiás states.
REFERENCES:
1. Plants of the World Online, Royal Botanic Gardens, Kew — Philodendron dardanianum
2. Kew Bulletin 46: 648 (1991) — protologue.