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1. Gnetum Linnaeus, Syst. Nat., ed. 12. 2: 612, 637; Mant. Pl. 1: 18, 125. 1767.
买麻藤属 mai ma teng shu
Morphological characters and geographical distribution are the same as those of the family.
Gnetum cleistostachyum C. Y. Cheng, in W. C. Cheng & al., Acta Phytotax. Sin. 13(4): 88. 1975, was described from SE Yunnan (Hekou Yaozu Zizhixian), but the name is invalid because the protologue indicated two collections (male and female) as types. It was based on material just at the start of anthesis, with rather deep, ± urceolate involucral collars tightly enclosing the flowers. Very little material of other species, at a similar developmental stage, was available for comparison, and it seems advisable to postpone validating this name until more complete collections, particularly with seeds, can be studied.
The name Gnetum indicum (Loureiro) Merrill IInterpr. Herb. Amboin. 77. 1917), based on Abutua indica Loureiro (Fl. Cochinch. 630. 1790), has been applied in the sense of G.
Montanum, but may in fact be the correct name for G. parvifolium. The taxonomic identity of G. indicum has often been questioned, and many herbaria followed F. Markgraf (Bull. Jard.
Bot. Buitenzorg, sér. 3, 10: 406. 1930), who dismissed it as being of uncertain application and placed most material so named in his new species, G. montanum. Type material of
Loureiro’s original species is available, including part of a seed not seen by Markgraf, which shows that it is not the same as G. montanum, even in the very wide sense used by
Markgraf, but closely resembles the species widely known as G. parvifolium (in the sense of which it has never been used). In order to prevent the name G. parvifolium from being
displaced, it seems best to follow Markgraf and formally propose that A. indica be rejected. It is also necessary to conserve, by lectotypification, the current application of G.
Montanum (see below). Many species are used in a variety of ways: the bark provides a strong fiber used for making ropes and nets; the sap flows very freely from cut stems and can be drunk to quench thirst;
the young leaves of some species are used as a green vegetable; and the seeds are roasted and eaten (the outer, fleshy layer contains irritant, needlelike crystals, and is not generally
eaten).
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Key based on female plants
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| 1 |
Shrubs or small trees; leaves drying yellowish; seed coat usually velvety, rarely glabrous |
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9 Gnetum gnemon |
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Vines; leaves drying dark green to brown or black; seed coat glabrous or with minute, silvery scales. |
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(2) |
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| 2 (1) |
Seeds clearly stipitate, stipe much longer than thick. |
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(3) |
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Seeds sessile or subsessile with stipe ca. as long as wide. |
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(6) |
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| 3 (2) |
Seeds 3-4 cm |
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1 Gnetum pendulum |
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Seeds (1-)1.2-2.5(-3) cm. |
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(4) |
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| 4 (3) |
Seed stipe 1.5-2.5 cm |
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2 Gnetum gracilipes |
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Seed stipe 0.2-0.6 cm. |
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(5) |
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| 5 (4) |
Seed cylindric-ovoid or cylindric, 0.65-0.9(-1.2) cm wide |
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3 Gnetum montanum |
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Seed broadly ellipsoid to subglobose, 1.4-2 cm wide |
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4 Gnetum catasphaericum |
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| 6 (2) |
Seeds 3-4 × 1.8-2.2 cm. |
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(7) |
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Seeds (1-)1.2-2.8 × (0.4-)0.5-1.6 cm. |
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(8) |
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| 7 (6) |
Female spikes with 12-21 involucral collars, 1.5-2.5 cm apart in fruit, each subtending 10-12 flowers |
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1 Gnetum pendulum |
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Female spikes with 8-11 involucral collars, to 3 cm apart in fruit, each subtending 6-12 flowers |
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6 Gnetum giganteum |
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| 8 (6) |
Seeds 1.1-1.6 cm wide. |
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(9) |
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Seeds (0.4-)0.5-0.9(-1.2) cm wide. |
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(10) |
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| 9 (8) |
Seeds (1.5-)1.9-2.1(-2.5) × 1.1-1.4(-1.6) cm, thinly fleshy, base rounded, apparent stipe not formed or very indistinct |
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7 Gnetum hainanense |
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Seeds 2.4-2.8 × 1.5-1.6 cm, very fleshy, base often contracted into an apparent stipe as long as wide when dried |
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8 Gnetum luofuense |
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| 10 (8) |
Seeds (1.3-)1.6-2.2 × (0.4-)0.5-0.8(-1) cm, 2-3.2 × as long as wide, surface longitudinally striate when dried |
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5 Gnetum parvifolium |
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Seeds (1-)1.2-1.5(-2) × 0.65-0.9(-1.2) cm, 1.6-1.85 × as long as wide, surface smooth or ± longitudinally wrinkled when dried, sometimes covered with silvery scales |
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3 Gnetum montanum |
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List of Keys
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Lower Taxa
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