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<div type="description"><p>Moderate, solitary, unarmed, pleonanthic, monoecious palm, sometimes flowering while still without an emergent trunk. Stem erect, often curved or slanting, becoming bare and conspicuously ringed with leaf scars. Leaves numerous, pinnate, neatly abscising; sheath fibrous, forming a woven supportive network with a conspicuous, tongue-like extension opposite the petiole, eventually disintegrating and becoming open; petiole short to long, adaxially channelled, abaxially rounded, bearing caducous tomentum abaxially; rachis elongate, curved or straight, adaxially angled near the tip, abaxially rounded, with caducous tomentum abaxially; leaflets very numerous, single-fold, regularly arranged in one plane, usually rather stiff, linear, acuminate, usually bifid with slightly asymmetrical tips, adaxially glabrous, abaxially with abundant, dot-like scales and very small ramenta along the midrib, midrib prominent adaxially, transverse veinlets evident. Inflorescences solitary, interfoliar, axillary, branched to 1 order, protandrous; peduncle ± elliptic in cross-section, robust, elongate, bearing scattered scales; prophyll tubular, 2-keeled laterally, opening apically, becoming fibrous, tomentose, persistent, ± obscured by the leaf sheaths; peduncular bract inserted near the prophyll, very large, tubular, entirely enclosing the inflorescence until shortly before anthesis, splitting abaxially, becoming boat-shaped, beaked, thick, woody, adaxially smooth, abaxially with longitudinal, shallow grooves and caducous tomentum; rachis ±equalling the peduncle, bearing spirally arranged rachillae, each subtended by an inconspicuous triangular bract and with a swollen base; rachillae robust, ± pendulous at first, later spreading with a basal bare portion and none or a few basal triads and pairs or solitary staminate flowers distally; rachilla bracts and floral bracteoles inconspicuous. Staminate flowers ± asymmetrical, narrowly ovoid, moderate, sessile; sepals 3, distinct, rather unequal, imbricate, triangular, ± keeled; petals much longer than the sepals, thick, rather leathery, distinct, valvate, irregularly boat-shaped, acute; stamens 6, filaments rather short, distinct, awl-shaped, fleshy, ± erect, anthers deeply sagittate basally, shallowly so at the apex, elongate, medifixed, ± versatile, latrorse; pistillode with 3, slender, pointed lobes. Pollen ellipsoidal, frequently elongate and/or pyriform, usually with either slight or obvious asymmetry; aperture a distal sulcus; ectexine tectate, finely perforate, perforate and micro-channelled, or perforate-rugulate, aperture margin slightly finer; infratectum columellate; longest axis 62–70 µm [1/1]. Pistillate flowers very large, globose in bud, becoming very broadly ovoid at anthesis; sepals 3, distinct, imbricate, ± rounded; petals similar to and somewhat longer than the sepals, lacking valvate apices, very leathery; staminodal ring low, membranous, not lobed; gynoecium trilocular at the very base, triovulate, broadly ovoid, obscurely 3-angled, extremely fibrous distally, stigmas 3, very short, borne in a slight depression, ovule anatropous, very small, laterally attached. Fruit very large (except in unusual forms), ellipsoidal to broadly ovoid, indistinctly 3-angled, dull green, brown, brilliant-orange, yellow, to ivory-coloured when ripe, perianth enlarging in fruit, stigmatic remains apical; epicarp smooth, mesocarp very thick and fibrous, dry, endocarp thick and woody, ± spherical to narrow ovoid, indistinctly 3-angled, with 3 longitudinal ridges, and 3, large, slightly sunken, basal pores, each with an operculum. Seed almost always 1 only, very large, with a narrow layer of homogeneous endosperm, and a large central cavity partially filled with fluid; embryo basal, opposite one of the endocarp pores. Germination adjacent-ligular; eophyll entire, broadly lanceolate. Cytology: 2n = 32.</p></div>
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<div type="fossil record"><p>Fruit or, more often, endocarps are the most frequently recorded fossils. The endocarps are distinguished by usually 3, sometimes more, well-defined pores. However, encocarps as large as those of Cocos nucifera are unknown. This suggests that the fossils may represent other genera within subtribe Attaleinae. Berry (1926b) first described Cocos zeylandica, a small endocarp (ca. 3.5 cm long), from Pliocene brown coal Cocos-bearing Beds in New Zealand (Mangonui, North Island); it was one of a number of specimens recovered. The endocarps are usually well-preserved and commonly washed up on the beach. Couper (1952), in his record of the pollen and spores of the Cocos-bearing Beds, notes that the rich flora of these beds had been recognised by geologists as early as 1872. From two pollen- and spore-rich samples, Couper (1952) records 4% and 8% abundance for Rhopalostylis/Cocos-type pollen (the two genera have closely similar pollen). Couper (1953) claims there can be little doubt that the commonly encountered palm pollen in the Cocos-bearing Beds is associated with Cocos zeylandica. However, although pollen of the two genera is closely similar in exine and size range (60–70 µm), whereas the pollen of other cocosoid palms with similar exine characteristics is smaller (<58 µm), it seems more reasonable to associate the fossil pollen with Rhopalostylis, a New Zealand palm. Further specimens of carbonised Cocos zeylandica were recovered from Miocene turbidites (possibly the result of a tsunami) at a different site in North Island by Ballance et al. (1981). From South Island, New Zealand (Otago Peninsula and Canterbury), Campbell et al. (2000) describe fossil endocarps (5–14.5 cm long) that have distinctive cocosoid pores, with the records from South Island ranging from mid-Eocene (45 million years ago) to Lower Oligocene (ca. 35 million years ago). Other records of fruits and seeds include silicified fruit (10 cm long x up to 9.5 cm wide) from the latest Pliocene of Australia (Queensland), which Rigby (1995) considers most resemble Cocos nucifera. Palmocarpon cetera, recorded from the Middle Oligocene of Puerto Rico, is compared with Cocos and Astrocaryum, although there is insufficient detail to make a satisfactory comparison (Hollick 1928). From the upper Cenomanien of France, Sainte Menehould area, Fliche (1894) describes an endocarp that bears a strong resemblance to cocosoid endocarps (6 cm in length, a thick testa 8 mm), to which he gives the name Cocoopsis. He also describes Cocoopsis ovata and C. zeilleri endocarps from the Lower Cenomanian of France (Fliche 1896); these have a diameter ranging from 41–60 mm, with a thick testa (8–12 mm). From India, Eocene (Rajasthan State), Cocos sahnii was described by Kaul (1951); large Cocos nucifera-like petrified fruit, 13 x 10 x 6 cm, with a thin epicarp, wide and fibrous mesocarp, and well-developed hardened endocarp are described from the Deccan Intertrappean deposits of Amarkantak, Madhya Pradesh (Tripathi et al. 1999) (although the age span of these volcanic deposits is controversial, see Chapter 5). A much smaller oval fruit (5 x 3 cm) with a smooth epicarp, fibrous mesocarp and stony endocarp, Cocos intertrappeansis, is recorded from the Tertiary of Mohgaonkalan (Madhya Pradesh) (Patil and Uphadhye 1984). An almost-complete Cocos-like palm stem, Palmoxylon sundaram, has been described from the Deccan Intertrappean beds of India by Sahni (1946). Although stem wood is difficult to identify to generic level, this is an interesting fossil and probably worth further study. Mahabalé (1978) discusses the fossil history and origins of the coconut. Harries (1978) comments, “... if the smaller-fruited coconuts identified in the New Hebrides Islands are taken into consideration, together with the (small) coconut fossil(s) in New Zealand, it may be suggested that the centre of origin was in the region of the submerged continental fragment of the Lord Howe Rise–Norfolk Ridge complex ... isolated from Australia about 80 my ago and apparently submerged below sea level about 15 my ago ...” However, it must be emphasised that determining the generic affinity of these fossils on the basis of their endocarps alone is problematic, as most of the genera of the Attaleinae are distinguished on morphological features unlikely to be preserved in the fossil record. </p></div>
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