Terminalia

  • Authority

    Stace, C. A. & Alwan, A.-R A. 2010. Combretaceae. Fl. Neotrop. Monogr. 107: 1-369. (Published by NYBG Press)

  • Family

    Combretaceae

  • Scientific Name

    Terminalia

  • Type

    Type. Terminalia catappa L.

  • Synonyms

    Terminalia catappa L., Buceras P.Browne, Bucida buceras L., Terminalia buceras (L.) C.Wright, Adamaram Adans., Kniphofia Moench, Panel, Myrobalanifera, Myrobalanifera citrina Houtt., Terminalia chebula (Gaertn.) Retz., Tanibouca, Tanibouca guianensis Aubl., Terminalia dichotoma G.Mey., Chuncoa, Chunchoa Pers., Badamia, Terminalia catappa L., Catappa, Terminalia bentzoe subsp. rodriguesensis Wickens, Myrobalanus, Pentaptera, Pentaptera angustifolia Roxb., Terminalia arjuna (Roxb. ex DC.) Wight & Arn., Vicentia, Vicentia acuminata Allemão, Terminalia acuminata (Allemão) Eichler, Chicharronia, Chicharronia intermedia A.Rich., Terminalia chicharronia (Griseb.) C.Wright, Terminaliopsis, Terminaliopsis tetrandus Danguy

  • Description

    Genus Description - Trees or shrubs, sometimes spiny, from ca. 0.5 m to 60(-70) m, the taller ones often with buttresses; combretaceous hairs the only trichomes present. Leaves spirally arranged, usually clustered at branchlet tips, sometimes with pocket-shaped or bowl-shaped domatia in secondary vein-axils, usually with petiolar glands. Inflorescence an axillary lax to congested simple leafless spike, the spikes often clustered at branchlet-ends, or rarely an axillary panicle of spikes; bracts very small and caducous. Flowers bisexual or andromonoecious, perhaps rarely dioecious, actinomorphic, sessile, 4- or 5-merous; lower hypanthium extended into a usually short distal "neck"; upper hypanthium cupuliform to campanulate, deciduous before fruiting or sometimes persistent; calyx lobes 4 or 5; petals 0; disk glabrous to densely pubescent; stamens 8 or 10, rarely 4, usually well exserted, with versatile anthers; style free, usually exserted, glabrous or pubescent, usually pubescent proximally and glabrous distally. Fruit 2-5-winged or -ridged or terete, flattened to actinomorphic, usually dry or spongy, sometimes slightly succulent. All species of Terminalia have small flowers borne in compact to elongated spikes. Terminalia lacks petals, and flower color comes from the upper hypanthium, and calyx lobes, and the filaments. These parts are variously described as white, cream-colored, yellow, or green. At the base of the upper hypanthium is a well-developed nectariferous disk, and many of the species are described as scented or fragrant, although a few are said to be scentless. They are clearly insect pollinated, and notes of visits by flies and bees are sometimes mentioned on labels. The inflorescences either have all bisexual flowers or are andromonoecious. In T. cat-appa the bisexual flowers are at the base of each spike and the males are more distal, so that fruits are borne only at the base of the rhachis. In contrast, the three species of section Ramatuellea have the opposite arrangement, so that the fruits are borne in a terminal head. In other species the two flower types are more mixed. In some cases sex expression is less regular. In T. fagifolia and T. eichleriana the inflorescences have variable proportions of male and bisexual flowers, and some specimens of the former species have some wholly male inflorescences. In T. amazonia and T. actinophylla (and possibly also T. glabrescens) the female organs (style, ovary, ovules) are variably developed, the intermediate flowers having small ovaries, very short styles, and tiny (presumably non-functional) ovules. In Terminalia the fruits vary from dry to slightly succulent and winged to wingless. In the Americas, apart from the introduced T. catappa and the enigmatic T. latifolia, all the traditionally recognized species of Terminalia (including Ramatuellea but not Bucida) possess winged fruits. These are radially symmetrical with three to five equal wings in sections Vicentia, Pachyphylla and Ramatuellea, but are elsewhere bilaterally symmetrical with two wings or asymmetrical with variably developed wings. The wings are thin and papery in section Chuncoa, and might be effective aids to wind dispersal, but in most other cases the fruits are quite heavy and the wings thick and stiff, and they might better act as sails allowing the fruits to be blown along on the ground. The two species of section Rhombocarpae have fruits that we believe to be unique in the genus. The proximal part of each of the two wings is thick and spongy, and surely aids in water dispersal these two species being riverine or littoral. The fruits of T. catappa have a similarly spongy mesocarp which would allow dispersal in the sea. Exell (1954) quoted observations from Java and Krakatau indicating that the fruits of this species are dispersed both by sea-water and by fructivorous bats. We know of no such observations in the Americas. The related T. latifolia is not littoral and the few fruits we have seen might be more succulent, suggesting animal dispersal. The three species of section Bucida have small dry, wingless achene-like fruits; no biological observations on these have come to our notice, but dispersal by animals, or by sea-water in coastal areas, is plausible. Polyembryony (two embryos producing two seedlings) was described by Sinha et al. (1993) in the Indian T. arjuna (Roxb.) Wight & Am. Over 60 counts on twelve species of Terminalia have been reported, but T. glabrescens (as T. brasiliensis) is the only native American species among them. This was reported with the hexaploid count 2n = 36 (Gibbs & Ingram 1982) in material from Sao Paulo, Brazil. In addition T. catappa has four counts with the tetraploid number 2n = 24, none from the Americas. The base number in Terminalia is x = 6 or 12; see under the family for details. Six of the species are represented by more than one ploidy level, and two of them (T. bellirica (Gaertn.) Roxb. and T. chebula Retz.) by four. For C-values see under introductory chapters.

  • Discussion

    Taxonomic History. Terminalia L. was founded in 1767 for the single species T. catappa L. In the next 100 years many extra species were described and about 14 extra genera founded in order to account for the wide variation displayed in fruit morphology. De Candolle (1828a, b) recognized Pentaptera and Chuncoa as well as Terminalia, but the late 20th century concept of this group was largely set by Eichler (1867), who amalgamated all these under Terminalia. The same generic concepts were upheld by Engler and Diels (1900) and Exell (1931), but Exell and Stace (1966) additionally recognized Terminaliopsis. In the last 20 years, however, more radical proposals have been made, based partly on the discovery of new species and partly on a desire to present a more evolutionary scheme.

    Vollesen (1981) showed that the traditional separation of the African Pteleopsis Engl, from Terminalia on the basis of its possession of petals broke down with the discovery of P. apetala Vollesen. He proposed that the distinction be redefined by basing 11 on the distribution of male flowers in andromonoecious inflorescences; in Pteleopsis they are proximal but in Terminalia they are distal (or all the flowers are bisexual). In fact they are also proximal in Ra-matuellea, now amalgamated with Terminalia, but Pteleopsis is distinct from Terminalia in other characters.

    Ramatuellea was described in 1825 for a distinctive Amazonian species (R. argentea Kunth), and two other related species are now known. Ramatuellea was separated from Terminalia on the basis of its andromonoecious inflorescences in which the male flowers are proximal, so that the fruits are borne in a tightly congested subspherical head. Although such separation is still possible, Ramatuellea clearly represents but one of several distinctive groups in Terminalia that could be similarly delimited. The subsequent discovery of the similar section Pachyphylla (Maguire & Exell, 1958) in the same area renders Ramatuellea far less distinctive, and Alwan and Stace (1989) reduced Ramatuellea to a section of Terminalia. This transfer removes the difference, based on sex distribution, between Terminalia and Pteleopsis.

    Bucida L. was described eight years before Terminalia, and its diagnosis (“Cal. 5-dentatus, superus. Cor. 0. Bacca monosperma”) could equally well apply to the latter. The three species of Bucida, all American, differ from Terminalia only in the small achene-like fruits which bear the persistent upper hypanthium on top. It therefore represents yet another distinctive group of Terminalia. Moreover there are three Madagascan species of Terminalia that also possess small rounded hard fruits bearing the persistent upper hypanthium (Capuron, 1967), so there is in any case no distinction. Stace (2007a) has amalgamated Bucida with Terminalia. Terminalia is conserved against Adamaram and Bucida.

    Useful regional revisions or floristic accounts of Terminalia are as follows. AMERICA: Eichler (1867); Exell (1935b, 1958); Stace (2007b, 2009); Stace & Alwan (1998); Standley & Williams (1962). AFRICA: Capuron (1967, 1973); Engler & Diels (1899-1900); Exell (1970, 1978); Exell & Garcia (1970); Griffiths (1959); Jongkind (1999); Keay (1954); Liben (1968, 1983); Perrier de la Bathie (1953, 1954); Wickens (1973). ASIA: Coode (1973); Exell (1954); Gan-gopadhyay & Chakrabarty (1997); Slooten (1924). AUSTRALIA: Byrnes (1977); Pedley (1990).

    Distribution and Ecology: Terminalia contains nearly 200 species, which are pantropical in distribution, occurring in tropical America, Africa, America, Australasia, and Oceania. It extends to southern subtropical regions in South America (to 37° 15' S), Australia (to 25°30' S), and Africa (to ca. 25° S); and to northern subtropical areas in North America (to 26°40' N). India (to ca. 31° N), and China (to ca. 28 N). Ihe greatest number of species and the greatest variation occur in eastern tropical Asia; only 34 species occur in the Americas, ca. 39 in Africa, and ca. 35 in Madagascar.