Musaceae Juss.

Milliken, W., Klitgard, B. and Baracat, A. (2009 onwards), Neotropikey - Interactive key and information resources for flowering plants of the Neotropics. http://creativecommons.org/licenses/by/3.0

Morphology General Habit

Large to giant suckering, glabrous herbs with sympodial rhizomes, short-thick underground stem (corm), erect pseudostems formed by overlapping leaf sheaths

Morphology Leaves

Leaves alternate, spirally arranged, simple, with course tubular sheath, petiole long (sometimes absent), margins entire (often split due to wind action), lanceolate or oblong, midrib distinct, venation closely set, parallel with slightly sigmoid lateral veins fusing near margins

Morphology Reproductive morphology Inflorescences

Inflorescence terminal, indeterminate, massive, pendent, sometimes erect, extensive thyrse with large distichous or spiraling, purple, spatheaceous, boat-shaped, deciduous bracts, enclosing a cincinnus (a dense monochasial cyme)

Morphology Reproductive morphology Flowers

Flowers unisexual and monoecious, zygomorphic, rarely bisexual in proximal part of inflorescence; basal flowers pistillate, apical flowers staminate, tepals 6, petaloid, outer ones and the inner 2 are fused into a 3-5- lobed tube, split on one side, inner tepal free, small, simple, scale-like, directed downwards, subtended by hyaline, recurved bracts; stamens 5 or 6 with one staminodial, alternating with perianth, filaments free from each other and perianth, filiform, anthers basifixed, opening via longitudinal slits; ovary inferior, syncarpous, carpels 3, 3-locular, style 1, filiform, ovules numerous, septal nectaries present

Morphology Reproductive morphology Fruits

Fruit a baccate, mostly indehiscent, oblong or cylindrical (banana-shaped) leathery, red-yellow, easily split longitudinally

Morphology Reproductive morphology Seeds

Seeds usually absent in Neotropical plants, c.9mm 5-15 mm in diam. when present, surrounded by a starchy, sweetish pulp derived from placental trichomes.

Note

Notes on delimitation: Has been broadly circumscribed in the past to include Strelitzia Aiton, Ravenala Adans., Phenakospermum Endl., Heliconia L. and often also Orchidantha N. E. Br. Currently treated as a family containing the genera Musa L. and Ensete Horan. (APG 2, 2003). In the pantropical order Zingiberales as part of the bananas alongside the gingers i.e. Cannaceae, Costaceae, Marantaceae and Zingiberaceae. Musaceae provide bananas Musa ×sapientum L. and plantains Musa ×paradisiacal L. Inflorescenceerect and self-pollinated or pollinated by sunbirds in SE Asia (hummingbirds in the Neotropics) or bat-pollinated and functional for only one night. Inflorescence represents the aerial stem. Number of genera: One Musa (30-50 species). One non-Neotropical Ensete (c.6 species).

Distribution

Often growing in dense stands in humid, lowland forest. Frequently cultivated as a food crop. From multiple origins in SE Asia from where they have been spread by man. Cultivated throughout the Neotropics preferring lowland forest.

Diagnostic

Key differences from similar families: Unisexual flowers vs. bisexual in Strelitziaceae and Heliconiaceae. Many ovules per locule vs. one ovule per locule in Heliconiaceae. Leaves spiral and fruit exarillate vs. leaves distichous and fruit arillate in Strelitziaceae. Torn leaves may appear superficially palm-like, however members of Arecaceae have truly pinnate or palmate leaves and a superiorovary. Massive leaves frequently torn by the wind. Purple, boat-shaped, caducous bracts. Stamens 5 (-6) the 6th one mostly staminodial. Distinguishing characters (always present): Large habit. Enormous inflorescence and infructescence usually weighed down by flowers or fruit. Unisexual flowers - basal flowers female, apical male. 6 petaloid tepals. Ovary inferior. Fruit a banana.

Timothy M. A. Utteridge and Laura V. S. Jennings (2022). Trees of New Guinea. Kew Publishing. Royal Botanic Gardens, Kew

Distribution

Musaceae is a family of two genera and 40–45 species with a natural distribution that covers tropical Africa, Madagascar, Indo-China, Malesia and northern Australia, although cultivated varieties of bananas are widespread in all tropical regions. Both native and cultivated representatives of both genera occur in New Guinea, including 13 wild species and an unknown number of cultivars and hybrids.

Ecology

Bananas are probably the second most important staple crop in New Guinea (after the sweet potato, Ipomoea batatas), and are cultivated from sea level to about 2000 m.

Morphology General Habit

Tree-like perennial herbs with rhizomes, overlapping leaf sheaths forming a pseudo-stem, often suckering, sometimes monocarpic. Leaves spirally arranged, very large, differentiated into sheath, petiole and blade, margins entire but usually torn along lateral veins by the wind, midrib prominent, secondary venation parallel, slightly sinuous, diverging at right angles from the midrib and converging at the margin

Morphology Reproductive morphology Inflorescences

Inflorescences terminal, often pendulous, indeterminate, numerous spathaceous bracts present, deciduous or persistent, each subtending a cluster of flowers, floral bracts absent

Morphology Reproductive morphology Flowers

Flowers unisexual and plants monoecious, rarely bisexual, zygomorphic, female flowers developing first, male flowers emerging distally later; tepals 6, petaloid, in 2 whorls, 3 outer tepals and 2 inner ones fused into a 5-lobed lamina, the other inner tepal free; stamens 5, staminode 1, filaments free; ovary inferior, syncarpous, 3-locular, numerous ovules per locule, placentation axillary, style filiform, stigma expanded

Morphology Reproductive morphology Fruits

Fruit baccate, indehiscent, oblong to cylindrical, exocarp leathery

Morphology Reproductive morphology Seeds

Seeds numerous, testa hard.

Musaceae, J.M.Lock. Flora of Tropical East Africa. 1993

Morphology General Habit

Giant herbs from a branched or unbranched corm-like rootstock

Morphology Leaves

Leaves arising from the apex of the corm, spirally arranged, very large; leaf-sheaths elongated, densely imbricate and forming a cylindrical pseudostem; lamina oblong, with a strongly channelled midrib and very many pinnately-arranged parallel lateral veins

Morphology Reproductive morphology Inflorescences

Inflorescence terminal on the corm, growing up through the centre of the pseudostem and thus appearing to arise from its apex

Morphology Reproductive morphology Flowers

Flowers unisexual, those on the proximal parts of the inflorescence ?, on the distal ?, borne in condensed groups subtended by spathaceous bracts

Morphology Reproductive morphology Flowers Calyx

Calyx spathaceous, splitting down one side, with ± 3 teeth at the apex

Morphology Reproductive morphology Flowers Corolla

Corolla lobes 3, 2 of them adnate to the calyx-tube, the third separate and directed downwards

Morphology Reproductive morphology Flowers Androecium

Stamens 6, but one usually rudimentary; filaments terete, thin; anthers dithecous with parallel thecae

Morphology Reproductive morphology Flowers Gynoecium

Ovary inferior, 3-locular; placentation axile; ovules many

Morphology Reproductive morphology Fruits

Fruit a large elongated fleshy 3-locular berry containing, in the wild species, numerous very hard subspherical seeds containing a straight embryo and copious endosperm