Dypsis thermarum

Dypsis (DIP-sis) thermarum (tehr-MAHR-uhm)
Ranomafana, Madagascar. Photo by Dr. John Dransfield, Royal Botanic Gardens, Kew/Palmweb.
Scientific Classification
Genus: Dypsis (DIP-sis) Species: thermarum (tehr-MAHR-uhm)
Synonyms
None set.
Native Continent
Africa
Morphology
Habit: Solitary & clustering. Leaf type: 4 to 10 blades.
Culture
Survivability index
Common names
Fanikara (Tanala).

Habitat and Distribution

Endemic to Madagascar. Only known from Ranomafana National Park. Humid montane rain

Ranomafana, Madagascar. Photo by Dr. John Dransfield, Royal Botanic Gardens, Kew/Palmweb.

forest, on steep slopes; alt. 800-1400 m.

Description

Slender solitary or clustering undergrowth palm, forming small clumps of up to 8 stems. STEMS to 2 m tall, 4-9 mm in diam., internodes 10- 42 mm long, dark green with pale yellow-green vertical striping, glabrescent, or with very sparse pale brown scales. LEAVES about 6 in the crown; sheaths 6-8 cm long, 0.6 -1 cm in diam., sparsely brown scaly, whitish or pale yellow-green, forming a well defined crownshaft, auricles present, rather narrow, 6-11 x 4-5 mm; petiole 4-14 cm long, 2 mm in diam., sparsely scaly; rachis 8-14 cm; leaflets 2-5 on each side of the rachis, ± equal, mostly composed of a single fold, occasionally with up to 4 folds, sometimes slightly irregular, 15-35 x 0.4-2.5 cm, adaxially lamina with scattered pale brown punctiform scales, abaxially with abundant pale brown punctiform scales and scattered bands of caducous dark brown scales. INFLORESCENCE branching to 1, very rarely to 2 orders, much shorter than the leaves; peduncle 10-16 cm long, about 2 mm wide; prophyll 9-12 x 0.5-0.7 cm, rather densely covered in reddish brown indumentum; peduncular bract similar to prophyll, exceeding it by 0.5-4 cm; rachis 5-10 cm, about 2 mm in diam., very densely covered in long laciniate dark red-brown hairs; rachillae 11-28, tending to diverge ± at right angles, short and rather stocky, 1.5-4 cm long, about 1.5 mm in diam., increasing slightly in diameter in fruit, somewhat angular, densely covered in red-brown laciniate hairs; rachilla bracts about 2 mm apart, short with numerous marginal laciniate hairs. STAMINATE FLOWERS rounded, about 1.5 mm in diam.; sepals rounded, irregularly keeled, 0.9 x 0.9 mm; petals triangular, striate, 1.2 x 1.4 mm; stamens 6, biseriate, antesepalous filaments 0.4 x 0.3 mm, antepetalous 0.5 x 0.3 mm, anthers didymous, 0.3 x 0.3 mm; pistillode absent. PISTILLATE FLOWERS globular, about 1.3 mm in diam.; sepals 1 x 0.4 mm, imbricate, keeled; petals 1.4 x 1.3 mm, broadly imbricate at the base, striate; staminodes 3 or more, irregular, minute; ovary about 1 mm in diam., with slightly eccentric stigmas. FRUIT orange at maturity, fusiform, 11 x 4 mm. SEED 7 x 3.5 mm; endosperm homogeneous, embryo lateral near the base. (J. Dransfield and H. Beentje. 1995)/Palmweb. Editing by edric.

This species appears to be a common palm of the forest undergrowth on steep slopes in the National Park at Ranomafana. It resembles D. angusta but can be distinguished by the staminate flowers having six rather than three stamens. The leaflets are also of a different texture. D. anovensis, known only from its type, is superficially similar, but has an inflorescence of very different form. Collections made in November 1994 (Dransfield & Beentje JD7511) have flowers at staminate anthesis, and these flowers appear to have six fertile stamens. Despite this, the affinities of the palm remain with the species formerly included in Trichodypsis. (J. Dransfield and H. Beentje. 1995)/Palmweb. Editing by edric.

Culture

Shady, sheltered, and moist. Likes it very humid. Hardiness USDA zones, 10A - 11.

Comments and Curiosities

This is clustering undergrowth palm that is abundant in the undergrowth in deep valleys of the Ranomafana National Park. It can easily be distinguished by its few narrow and long leaflets and the densely hairy short inflorescences. It forms rather untidy clumps at the foot of steep slopes. The species name is the Latin for "of the hot springs", a translation of the Malagasy ranomafana. (J. Dransfield and H. Beentje. 1995)/Palmweb.

Conservation: Rare, probably not at present under threat, despite being geographically restricted. (J. Dransfield and H. Beentje. 1995)/Palmweb.

Uses: Stems used for making traps to catch crayfish.