Tamarix L.

Undershrubs, shrubs or trees, glabrous, papillose or subpapillose. Leaves scalelike, sessile, amplexicaul, auriculate or vaginate. Flowers in racemes or panicles on younger (aestival) or older (vernal) branches, bracteate, mostly bisexual rarely unisexual with plants dioecious. Calyx 4 - 5-lobed; lobes ovate to suborbicular, obtuse, rounded or acute at apex, subequal or equal. Petals 4 - 5, ovate, elliptic, oblong or obovate, obtuse and often slightly notched at apex, caducous or persistent. Stamens 4 - 10 (-12), haplostemonous, diplostemonous or partially diplostemonous with antisepalous stamens, usually slightly longer than antipetalous ones, inserted on or below the nectariferous disc; anthers ovoid, apiculate, acute or obtuse, equally or unequally 2-lobed at base. Disc variously shaped. Ovary pyramidal; styles 3 - 4, rarely 2 or 5 (3 in Indian species), free or rarely connate at base; stigmas spathulate. Capsules pyramidal, 3-valved. Seeds many, small with sessile coma.

Chiefly in saline areas of deserts, semideserts and steppes or on mountains along rivers in Europe, Africa and Asia; ca 60 species; 9 in India.

Literature. BAUM, B.R. (1978). The genus Tamarix, pp. 208. Israel Academy of Sciences and Humanities, Jerusalem. BAUM, B.R. et al. (1971). Pollen morphology of Tamarix species and its relationship to the taxonomy of the genus. Pollen et Spores 13: 495 - 521 (It also includes the palynology of Myricaria elegans (Royle) Ovcz. & Kinz. which Baum et al. treat as Tamarix ladachensis Baum). QAISER, M. (1981). The genus Tamarix Linn. (Tamaricaceae) in Pakistan. Pakistan J. Bot. 13: 107 -158.

Notes. Several species of Tamarix are cultivated as ornamentals prized for their feathery verdure and pink bloom. They also have medicinal properties and yield useful wood. They are also useful in arresting soil erosion and act as wind breakers. The galls formed on twigs are used for dyeing and tanning purposes.

KEY TO THE SPECIES

1a. Flowers unisexual; plants dioecious

3. Tamarix dioica

b. Flowers bisexual

2

2a. Androecium haplostemonous; stamens 5

3

b. Androecium diplostemonous or partially diplostemonous; stamens 10 or 6 - 10

7

3a. Leaves vaginate; racemes spirally twisted

1. Tamarix aphylla

b. Leaves pseudo-vaginate, amplexicaul or narrowed at base; racemes not spirally twisted

4

4a. Leaves pseudo-vaginate or amplexicaul; sepals rounded or truncate at apex; plants of plains

5

b. Leaves narrowed at base; at least some sepals acute at apex; plants of high altitude

6

5a. Rachis glabrous to sparsely papillose; racemes 3 - 4 (-5) mm broad; lobes of disc notched; filaments mesodiscine

5. Tamarix Indica

b. Rachis densely papillose; racemes 5 - 7 mm broad; lobes of disc not notched; filaments epilophic to confluent epilophic

8. Tamarix pakistanica

6a. Lobes of disc notched; filaments mesodiscine

2. Tamarix arceuthoides

b. Lobes of disc not notched; filaments confluent epilophic

7. Tamarix leptostachya

7a. Leaves vaginate in lower part; racemes 1 - 1.5 (-2) cm broad; bracts more than 2 mm long; petals irregularly denticulate in upper half;stamens 10; disc fleshy

4. Tamarix ericoides

b. Leaves amplexicaul or semi-amplexicaul; racemes 5 - 8 mm broad; bracts less than 2 mm long; petals entire, often emarginate; stamens 6 -10; disc not fleshy

8

8a. Petals 2 - 2.5 x 1 - 1.5 mm; disc lobed; filaments epilophic; capsules less than 7 mm long

6. Tamarix kutchensis

b. Petals 3 - 4.5 x 2 - 2.5 mm; disc not lobed; filaments epidiscine; capsules more than 8 mm long

9. Tamarix passerinoides

List of Lower Taxa