https://dx.doi.org/10.4314/ijs.v20i2.18 Ife Journal of Science vol. 20, no. 2 (2018) 371

VEGETATIVE AND REPRODUCTIVE MORPHOLOGICAL STUDY OF SOME SPECIES IN THE FAMILY COMBRETACEAE IN NIGERIA

1*Akinsulire O. P, 1Oladipo O. T, 1 Illoh H. C and 2 Mudasiru O. M 1Department of Botany, Obafemi Awolowo University, Ile-Ife, Nigeria. 2Department of Botany, University of Ibadan, Ibadan, Nigeria. * E-mail of corresponding author: [email protected], Tel.: +234 703 320 7527 (Received: 27th April, 2017; Accepted: 28th April, 2018)

ABSTRACT

A qualitative and quantitative morphological study of eleven species representing four genera in the family Combretaceae was conducted in search of inter- and intra-generic characters which may be of taxonomic use in the identification and classification of the family, as well as enhancing the understanding of the taxonomy of the family. Collection of accessions was done from different parts of southern Nigeria. Life plants, fruits, flowers and seeds from mature plants were collected and subjected to morphological studies. Both qualitative and quantitative characters were recorded. Quantitative data were subjected to analysis of variance, single linkage cluster analysis (SLCA) and principal components analysis (PCA). Morphological characters which separate the taxa include leaf shape, leaf apex, presence of hairs, and colour of reproductive parts such as pedicel, stamen, sepal, petal, style and stigma. Quantitative vegetative and reproductive morphological characters vary significantly (P = .05) among the taxa. The presence of undulating leaf margins and cladodromous venation in Terminalia mantaly, an introduced species is diagnostic for the species.

Keywords: Combretaceae, Diagnostic, Morphology, Reproductive, Taxonomy, Vegetative

INTRODUCTION Engl. & Diels., genus Terminalia: T. catapa L, T. Combretaceae, one of the families of flowering superba Engl. & Diels., T. ivorensis A. Chev., T. plants in the order Myrtales consists of 23 genera mantaly H. perr., T. avicennioides Guill. & Perr., and about 600 species (Stace, 2007). Hutchinson Anogeissus leiocarpus (DC.) Guill. & Perr. and and Dalziel (1958) established that Combretaceae Quisqualis indica L., the only West African consists of nine genera while Mabberley (2008) representative species of the genera Anogeissus and opined that Combretaceae comprises of trees, Quisqualis. shrubs and lianas distributed predominantly in tropical and subtropical Africa, but also in central MATERIALS AND METHODS and southern America, southern Asia and Collection of plants were made from different northern Australia. In West Africa, Combretaceae locations in southern Nigeria. The samples were has nine genera with about 72 species, of which identified at the Herbarium of the Department of Combretum Loefl. is the largest genus with 49 Botany, Obafemi Awolowo University (IFE). Five species (Gill, 1988). However, Keay (1989) accessions for each of the species were later reported 25 species of straggling shrubs or lianas subjected to morphological examinations. in the genus Combretum which are found in Nigeria. Qualitative as well as quantitative attributes of Hutchinson and Dalziel (1958) established that a vegetative and reproductive morphological number of species are indeterminate and occur in characters of the accessions collected were the south-eastern Nigeria. studied and documented as the reproductive parts were also assessed both qualitatively and The present study is therefore aimed at describing quantitatively. Data collected from this the qualitative and quantitative morphological documentation were subjected to cluster analysis characters of eleven species belonging to four and principal component analysis. Photographs genera-Combretum, Terminalia, Anogeissus and of some of the morphological characters of the Quisqualis of the family Combretaceae in Nigeria. taxa were also made. The representative species of the genus Combretum include: C. platypterum Hutch. & Dals., C. racemosum RESULTS Engl. & Diels., C. zenkeri P. Beauv., C. dolichopetalum Combretum platypterum (Welw.) Hutch. & 372 Akinsulire et al.: Vegetative and Reproductive Morphological Study

Dals. (Plates 1a - d) acute, base cordate, veins prominent beneath, Habitat and Habit: tropical regions. A scandent 12.03±0.54 cm long and 7.17±0.34 cm wide. shrub or forest liana, up to 10 m long Petiole round and pubescent, 1.67±0.07 cm long Stem: unarmed, weak, suffrutescent, bark green Venation: Eucamptodromous to grey and often flaking. Inflorescence and Flower: axillary, branched, Leaf and Petiole: leathery and shiny, green to globose head surrounded by abundant whitish dark-green, glabrous at both surfaces, opposite, leaves. Flower small, whitish and fragrant, flowers unarmed, obovate, margins entire, estipulate, apex are in long spike, ovary inferior. acute or acuminate, base acute or cuneate, Pedicel: pubescent, 0.20±0.00 cm long. 13.61±0.26 cm long and 5.98±0.17 cm wide. Sepal and Petal: short (0.15±0.00 cm) long, Petiole round, glabrous, 1.45±0.23 cm long cream-coloured or slightly whitish, acute at the Venation: Eucamptodromous apex. Petals cream-coloured, acute, densely Inflorescence and Flower: cluster, axillary, pubescent, 0.20±0.00 cm long spike-like raceme, generally more or less Stamen: short (0.44±0.01 cm) long and whitish. tomentose. Flowers are bisexual, regular, and are Style and Stigma: densely pubescent, 0.59±0.02 borne in axillary or terminal branched or c m l o n g . unbranched spikes, and are bracteates. Flowers are Fruit and Seed: one-seeded, dry indehiscent, 4-or 5-merous variable in shape and size, almost round, 5- Pedicel: pubescent, 0.42 ± 0.01 cm long. winged, whitish, cream to pale-brown, 1.65±0.01 Sepal and Petal: fused with petals in an alternate cm in diameter; Seed tiny (0.67±0.01 cm long and manner, cream or pinkish, acute at the apex, 1.65± 0.12±0.01 cm wide), spindle-shaped, greenish to 0.08 cm long. Petal vary from white, cream- brownish. coloured, yellow, but are sometimes pale to deep pink or bright red, ovate, apex acute, 2.03±0.10 cm Combretum racemosum P. Beauv. (Plates 3a - d) long. Habitat and Habit: forest or tropical regions. A Stamens: inserted on the hypanthium, usually scandent shrub or forest liana that produces from twice as many as the petals, and usually extended seeds and basal shoot re-growth beyond the petals, filaments red, anthers vary in Stem: stem is round, covered with long weak colour from yellow, orange, pinkish, crimson or hairs, armed with spines that are sparsely reddish to red-brown, 1.87±0.43 cm long. distributed, weak, suffrutescent, bark green to Style and Stigma: fairly glabrous, cream coloured grey; bark on young stems is often flaking and or pinkish, 3.87±0.11 cm long. peeling in stringy strips or threads. Fruit and Seed: fruit glabrous or covered with Leaf and Petiole: opposite, leathery, green to short hairs and is mainly a 4-5 winged samara, red dark-green, young leaves pubescent at the upper at first then pale yellow, 2.81±0.03 cm in diameter; surface glabrous beneath, matured leaves Seed whitish, spindle-shaped, 1.07±0.02 cm long glabrous at both surfaces, leaves opposite, sub- and 0.36±0.01 cm wide. opposite, unarmed, obovate, margins entire, estipulate, apex acute, base cordate, 12.12±0.23 Combretum zenkeri Engl. & Diels. (Plates 2a - cm long and 5.54±0.05 cm wide. Petiole round, d) pubescent, 0.82±0.03 cm long Habitat& Habit: savannah and secondary forest; Venation: Eucamptodromous. common in places and widely distributed. A Inflorescence and Flower: densely flowered- scandent shrub or forest liana, to 27 m high spike, with flowers in large panicles, surrounded Stem: armed with spines, weak, suffrutescent, by conspicuous white or pink bract-like leaves bark green to grey; sometimes dark-brown, bark subtending the flower clusters. Flower crimson; on young stems is often flaky and peeling in pink or dark-red, with hairy flower tubes, clustered stringy strips or threads. in short glomeruliform or umbel-like spikes Leaf and Petiole: opposite, sub-opposite, green arranged in a large panicle. to dark-green, pubescent at both surfaces, Pedicel: pubescent, 0.24±0.01 cm long unarmed, obovate, margins entire, estipulate, apex Sepal and Petal: greenish, cup-like, acute at the Akinsulire et al.: Vegetative and Reproductive Morphological Study 373 apex, 0.64±0.01 cm long. Petals red or crimson, Stem: unarmed, stem surface coarse and pilose outside, not incurved, elliptic to ovate, acute shallowly fissured, grey to dark-brown. at the apex, 0.27±0.01 cm long Leaf and Petiole: leaf leathery, glabrous at both Stamen: curly and pinkish, 1.40±0.02 cm long. surfaces, dark-green, turning bright yellow then Style and Stigma: glabrous, 1.57±0.03 cm long. vivid to dark red before falling, crowded at the Fruit and Seed: one-seeded, white, cream or terminal ends of branchlets, unarmed, obovate, pinkish, sometimes dark-red, fruit is four to five- margins entire, estipulate, apex acute, obtuse to winged. Fruit is 2.53±0.03 cm in diameter. Seed retuse, base acute, cordate to lobate, 22.28±1.07 elliptic or spindle – like, greenish, 0.96±0.02 cm cm long and 13.17±0.54 cm wide. Petiole round, long and 0.30±0.00 cm wide petiole of matured leaves pubescent, those of young leaves almost glabrous, 1.78±0.06 cm long Combretum dolichopetalum Engl. & Diels. Venation: Eucamptodromous. (Plates 4a - d) Inflorescence and Flower: inflorescence cluster. Habitat and Habit: forest; secondary re-growth Flowers are small, white or cream-coloured, five areas, usually near rivers. A scandent shrub or lobed, arranged on long axillary spikes with a forest liana mildly unpleasant smell, valvate aestivation and Stem: unarmed, weak, suffrutescent, bark grey to actinomorphic. dark brown; young stems hairy. Pedicel: short (0.31±0.02 cm long), flowers sub- Leaf and Petiole: pubescent at both surfaces, sessile, fruits sessile. leaves are opposite or sub-opposite, unarmed, Sepal and Petal: sepals regularly arranged, obovate or elliptic, margins entire, estipulate, apex triangular with acute apex, white to cream in cordate or acuminate, base cordate or lobate, colour, 0.25±0.01 cm long. Petal absent 6.99±0.19 cm long and 4.08±0.48 cm wide. Stamens: filaments tiny (0.44±0.01 cm long) and Petiole short (0.33±0.02 cm long), sub sessile, glabrous. round and pubescent. Style and Stigma: furcate, distinguishable from Venation: Eucamptodromous. filament, glabrous, 0.61±0.02 cm long. Inflorescence and Flower: inflorescences Fruit and Seed: sessile, one seeded, fleshy, terminal and axillary with long spreading hairs. laterally compressed, and ovoid to ovate, smooth- Flower regular, 5-merous, and often hidden by the skinned drupe. Unripe fruit green to dark- large yellow-green bracts; purplish, ripe fruit yellow to red, fruit 4.75±0.21 Pedicel: pubescent, 0.56±0.03 cm long. cm long and 3.66±0.11 cm wide. Seed enclosed in Sepals and Petals: sepal short (0.19±0.01 cm a rind of light, pithy or corky tissue, 1.98±0.06 cm long), triangular, acute at the apex. Petals long and 0.73±0.02 cm wide. lanceolate, 1.93±0.04 cm long, usually yellow with crimson streak within. Terminalia superba Engl. & Diels (Plates 6a - d) Stamens: usually 10, free and glabrous, 2.71±0.02 Habitat and Habitat: forest tree of tropical West cm long, ovary inferior. Africa. A woody tree (up to 45.72 m high) with Style and Stigma: style short (0.26±0.00 cm large thin buttresses, clean straight bole and a long), glabrous. doomed flat crown, and a trunk typically clear of Fruit and Seed: one seeded, glabrous or softly branches for much of its height, buttressed at the covered with hairs, fruits mainly a 4-5winged base. samara; 1.93±0.03 cm in diameter. Seed: Stem: unarmed, with slightly coarse ashy-grey 1.09±0.03 cm long and 0.34±0.01 cm wide. surface, almost glabrous, bark surface smooth and grey in young trees; inner bark soft-fibrous and Terminalia catapa Linn. (Plates 5a - d) pale yellow. Habitat and Habit: sub-tropical and tropical Leaf and Petiole: thinly leathery and glabrous, regions. A woody tree (up to 24.10m high), crowded at the terminal ends of branchlets, extensively flat topped, with a wide horizontal pinnately veined, unarmed, obovate, margins canopy of evenly distributed foliage arising from entire, estipulate, apex acute, base acute, 17.86 the apex of the straight bole. ±0.46 cm long and 8.98±0.26 cm wide. Petiole 374 Akinsulire et al.: Vegetative and Reproductive Morphological Study round, glabrous, 4.18±0.16 cm long elongated and narrow, finely tomentose with very Venation: Eucamptodromous short reddish or orange-brown hairs, 6.52±0.08 Inflorescence and Flower: Inflorescence an cm long and 2.60±0.08 cm wide, including the axillary spike, short-hairy. Flower small and wings. Seed oval and glabrous, 0.92±0.02 cm long whitish, growing in loose spikes, flowers bisexual and 0.28±0.01 cm wide or male, regular, usually 5-merous; receptacle spindle-shaped. Terminalia mantaly H. Perr. (Plates 8a - d) Pedicel: usually short (0.44±0.01 cm long) and Habitat and Habit: mesophytic, a tree of west glabrous. Africa dry zones, a native of Madagascar but Sepal and Petal: triangular, (0.26±0.01 cm long). introduced and widely cultivated in Nigeria; used Petal absent as shade tree and as ornamentals. A woody tree (up Stamens: usually 10, free, densely woolly hairy; to 22.86 m high), flat topped, with a wide ovary inferior, 1- celled, 0.33±0.00 cm long. horizontal canopy of evenly distributed foliage Style and Stigma: style long (0.46±0.001 cm), arising from the apex of the straight bole sparsely hairy. Stem: unarmed, with smooth stem surface and an Fruit and Seed: a winged samara or nut, one ashy-grey bark. seeded, transversely oblong-elliptical in outline, Leaf and Petiole: bright-green when young, 1.79±0.01 cm long and 5.28±0.08 cm wide, dark-green at maturity, in terminal rosettes of 4-9 including the wings. Seed golden brown, glabrous, unequal leaves on short stem, leaves leathery, 1.048±0.01 cm long and 0.28±0.01 cm wide glabrous at both surfaces and unarmed, obovate, margins wavy, occasionally entire, estipulate, apex Terminalia ivorensis A. Chev. (Plates 7a - d) obtuse, base acute, 2.69±0.14 cm long Habitat and Habit: forest, tropical regions. It is a and1.39±0.08 cm wide. Petiole sub-sessile, round woody tree, to 45.72 m high, or more, with broad and glabrous; 0.19±0.01 cm long blunt buttresses and clean straight bole. Venation: Cladodromous. Stem: unarmed, bark dark-brown bark or blackish Inflorescence and Flower: inflorescence cluster. fissured. Flowers are small, white or cream, five lobed, Leaf and Petiole: unarmed, glabrous at both arranged on long axillary spikes, with a mildly surfaces and often crowded at the terminal ends unpleasant smell, valvate and actinomorphic. of branchlets, oval to obovate, margins entire, Pedicel: short (0.18±0.01 cm long), glabrous, estipulate, apex acute or obtuse, base acute, leaf flowers sub-sessile. 10.61±0.22 cm long and 4.55±0.12 cm wide. Sepal and Petals: whitish or creamson, connate Petiole round, long-petiolate, pubescent, and acute at the apex, 0.20±0.00 cm high. Petal petiole1.19±0.04 cm long absent Venation: Eucamptodromous Stamens: filaments tiny (0.46±0.01 cm long), Inflorescence and Flower: an axillary spike, glabrous, bearing the ovoid anthers.. slender and whitish short-hairy. Flower bisexual or Style and Stigma: glabrous, 0.47±0.02 cm long. regular, 5-merous and pale yellow. Fruit and Seed: Fruit sessile, fleshy and one Pedicel: usually short (0.48±0.02 cm long), seeded drupe, laterally compressed, ovoid to ovate slightly pubescent, spindle-shaped. or elliptic, unripe fruit green to dark-purplish, ripe Sepal and Petal: triangular and short, 0.33±0.01 fruit yellow to red, typically, one to many fruits cm. Petal absent with variable sizes develop on the basal part of the Stamens: 10, free, disc annular, densely woolly flower spike. Fruit is 1.91±0.05 cm long and hairy. Filaments tiny (0.46±0.01 cm long), 0.97±0.04 cm wide. Seed is spindle-shaped, glabrous and bearing the ovoid anthers, glabrous, 0.76±0.02 cm long and 0.30±0.00 cm Style and Stigma: woolly glabrous, whitish to wide. creamy, style 0.51±0.12 cm long. Ovary: inferior, unilocular Terminalia avicennioides Guill. & Perr. (Plates Fruit and Seed: longitudinally winged nut, one 9a - d) seeded, oblong in outline, variable in size, Habitat and Habit: savannah or forest. A woody Akinsulire et al.: Vegetative and Reproductive Morphological Study 375 tree (up to 19.81m high), with short bole, sometimes Stem: unarmed but coarse; bark is grey to mottled bushy, branching from the base. pale and dark brown, scaly, flaking off in Stem: unarmed, with coarse surface, roughly rectangular patches, fibrous and exuding a dark fissured and black to dark-brown or rough grey. gum. Leaf and Petiole: unarmed, leathery, mature leaf Leaf and Petiole: alternate or nearly opposite, greyish-green above and slightly white beneath, simple and entire, broadly elliptic or ovate in dark brownish, sometimes extremely abundant outline, apex acute, base acute, pubescent or and often crowded at the terminal ends of covered in dense silky hair when young; estipulate; branchlets, adaxial surface glabrous and densely 2.31±0.10 cm long and 1.45±0.09 cm wide. pubescent or velvety whitish-hairy on the abaxial Petiole round and pubescent, petioles are short surface, obovate, margins entire, estipulate, apex without glands; (0.20±0.02 cm) long acute or obtuse, base acute, 14.66±0.41 cm long Venation: Eucamptodromous and 7.75±0.19 cm wide. Petiole round and Inflorescence and Flower: inflorescence cluster, pubescent, 3.26±0.09 cm long dense globose head, one or more peduncle from Venation: Eucamptodromous, pinnately veined the same leaf axil, bracteote very minute, nearly with 10-12 pairs of barely prominent lateral veins. pubescent. Flower pentamerous, pale yellow or Inflorescence and Flower: terminal and axillary, greenish yellow and fragrant. spikes, racemes, or sometimes panicles, bracteates Pedicel: round, pubescent, 1.85±0.06 cm long. and velvety hairy, somewhat fairly pink. Flowers Sepal and Petal: connate into a lobed usually regular, bisexual, sometimes bisexual and campanulate cup, 0.35±0.01 cm high. Petal absent male flowers present in same inflorescence. Stamens: Stamens 10, exserted, 0.50±0.01 cm Receptacle spindle shaped, surrounding and long, filaments filliform. adnate to ovary and extended into a short or long Style and Stigma: style simple, filiform, calyx tube dilated distally; lobes 4 or 5, valvate in 0.54±0.01 cm long. bud Fruit and Seed: one seeded rounded samara with Pedicel: softly pubescent, 0.44±0.01 cm long. 2 wings, yellowish to reddish brown; fruits almost Sepal and Petal: 0.28±0.01 cm high, acute and glabrous, orbicular, laterally winged, crowded in a velvety hairy. Petal absent globose head, 0.60±0.01 cm in diameter. Seed Stamens: 10 and free, stamens usually as many as enclosed horizontally in a dense cone-like calyx lobes in 2 series, inserted inside distal part of fructification, 0.43±0.01 cm long and 0.14±0.00 calyx tube, filaments incurved in bud; 0.49±0.01 cm wide. cm high. Ovary: inferior and unilocular Quisqualis indica Linn. (Plates 11a - d) Style and Stigma: style 1, simple, usually free Habitat and Habit: secondary forests and often in from distal part of calyx tube, stigma capitate or river banks; cultivated and naturalized in tropical inconspicuous, 0.58±0.01 cm long. areas. A scandent (climbing) shrubby vine, Fruit and Seed: one seeded, fruit a winged nut, mesophytic to xerophytic, or helophytic; widely majorly oblong-elliptical in outline, fleshy or dry, cultivated as an ornamental plant. indehiscent, often longitudinally 2-5-winged, Stem: suffrutescent, green when young and 6.42±0.11 cm long and 2.50±0.03 cm wide greyish-brown at maturity. including the wings, velvety hairy and whitish. Leaf and Petiole: opposite (or sub-opposite), Seed is spindle shaped 1.08±0.02 cm long and oblong; obovate or elliptic, petiolate and simple, 0.33±0.01 cm wide. base obtuse; apex acute; margin entire; pinnately veined; glabrous at both surfaces and exstipulate. Anogeissus leiocarpus (DC.) Guill. & Perr. 12.14±0.26 cm long and 6.32±0.15 cm wide. (Plates 10a - d) Petiole short (1.02±0.03 cm long) petiole round Habitat and Habit: driest savannah to the and glabrous. borders of the forest zones, usually in moist Venation: Eucamptodromous situations but also in relatively dry situation. A Inflorescence and Flower: cluster and terminal, tree, up to 21.34m high or axillary; usually racemose. Flower pale-pink, 376 Akinsulire et al.: Vegetative and Reproductive Morphological Study white to red, star shaped and fragrant; corymb; petiole surfaces in C. zenkeri and C. dolichopetalum shallow corolla sinus. and adaxial surface and petiole in C. racemosum is Pedicel: greenish to brownish, softly pubescent; classificatory (Table 1). However, characters of 0.92±0.02 cm long. unification in the genus Combretum include entire Sepal and Petal: regularly arranged with an acute leaf margins. The variations that were discovered apex acute greenish in colour, 0.37±0.02 cm long. in the reproductive parts are also useful in the Petals star-shaped, whitish, reddish or pinkish; delimitation of the taxa. C. racemosum and C. 2.26±0.04 cm long dolichopetalum are characterized by green petals and Stamens: filaments tiny and glabrous, 5.11±0.05 acute sepal apex, while pink/cream-coloured cm long. sepal, as well as acute sepal apex can be used in Style and Stigma: style (7.02±0.07 cm long) and grouping C. platypterum and C. zenkeri (Table 2). glabrous. Petal colour in this genus varies and has Fruit and Seed: one seeded; non-fleshy; classificatory value as pink/white/cream petal indehiscent, schizocarp or drupe; oblong with colour in C. platypterum and cream-coloured petal sharp angles, glabrous black; usually pentamerous in C. zenkeri delimits the taxa. Red/cream- and ellipsoidal, 3.32±0.03 cm long and1.77±0.04 coloured petal is peculiar to C. racemosum while cm wide. Seed non-endospermic; ellipsoidal, yellow/light-green petal separates C. embryo well differentiated; cotyledons 1-3, dolichopetalum. However, whitish seed colour, 1.55±0.03 cm long and 1.00±0.03 cm wide peculiar only to C. platypterum is diagnostic for the taxon, separating it from other members of the DISCUSSION genus Combretum. In taxonomic studies morphological characters have always been useful in delimiting taxa. In the genus Terminalia, oval leaf delimits T. Hutchinson and Dalziel (1958) have used some of ivorensis as obovate leaf shape characterize other the morphological attributes to characterize members of the genus (Table 1). Acute leaf apex is species in the family Combretaceae except some also classificatory of the taxa as it can be used in characters like leaf margin, leaf apex, venation; grouping T. superba and T. mantaly, while colour of reproductive parts like sepal, petal as obtuse/retuse leaf apex delimits T. catapa. well as morphology of style and stigma, filament However, acute/obtuse leaf apex found in T. and pedicel which are important in the taxonomy ivorensis and T. avicennioides is classificatory for the of the genera in the family Combretaceae. species. Leaf margin is also worthy of note in this Morphological characters have also been used by genus. Other members of the genus Terminalia other researchers to enhance the taxonomy of have entire leaf margins while entire/undulating different taxa (Smith and Ashton, 2006; Adedeji leaf margin clearly delimits T. mantaly which was and Faluyi, 2006). not described by Hutchinson and Dalziel (1958) but newly introduced. Diagnostic character which There is uniformity in obovate leaf shape in the is also of great taxonomic value in the genus genus Combretum (Table 1) except in Combretum includes Cladodromous venation, peculiar only to dolichopetalum where it is elliptic. This character is T. mantaly (Table 1). Its delimitation however arises therefore diagnostic for C. dolichopetalum. Similarly, owing to the fact that it is the only mesophytic leaf apex is of classificatory importance in this species in the genus. Leaf base is not only genus: acute leaf apex can be used in grouping C. classificatory but also diagnostic for the genus zenkeri and C. racemosum while acute and Terminalia. Acute and occasionally cordate or occasionally cordate or acuminate leaf apex can be lobate leaf base is common to T. catapa and it used to classify C. platypterum and C. dolichopetalum delimits the taxa from other species of Terminalia. (Table 1). Cordate leaf base is also classificatory of However, the occurrence of numerous woolly or C. zenkeri and C. racemosum, however, acute or velvety hairs on the abaxial surfaces of leaves in T. occasional cuneate leaf base delimits C. platypterum avicennioides as well as petiole surfaces in T. while cordate or lobate leaf base delimits C. avicennioides and T. ivorensis delimit the taxa from dolichopetalum (Table 1). The occurrence of hairs other members of the genus (Table 1). Pubescent on the adaxial and abaxial surfaces of leaves and pedicel surface is classificatory for T. ivorensis and Akinsulire et al.: Vegetative and Reproductive Morphological Study 377 T. avicennioides and makes the species to be vegetative and reproductive morphological morphologically more closely related to each attributes have proved to be useful in bringing to other than to any other species in the genus (Table the fore, inter- and intrageneric relationships 2). existing among members of the family Combretaceae. Character like leaf length, leaf Ripe fruit colour is also of diagnostic value in the width and petiole length vary significantly among genus Terminalia as dark-brown ripe fruit is some of the species of Combretaceae studied peculiar to T. superba, T. ivorensis and T. avicennioides. (Tables 3 and 4). This indicates that these This however is owing to the fact that they are characters are taxon specific, and could therefore forest species, while yellow/red ripe fruit delimits be used in separating the species. However, some T. catapa and T. mantaly which are tropical and members of the Genus Combretum: C. zenkeri, C. mesophytic taxa respectively. racemosum, and the monotypic Genus-Quisqualis, represented by Q. indica show no significant Among all the eleven species of Combretaceae difference in their leaf length indicating a close covered in this study, the presence of hairs on the relationship in their leaf morphology. Leaf width adaxial and abaxial surfaces of leaf in Combretum is not significantly different also in Combretum zenkeri, Combretum dolichopetalum, Anogeissus zenkeri and Terminalia avicennioides as well as in leiocarpus and Combretum racemosum is of taxonomic Combretum dolichopetalum and Terminalia ivorensis, importance and can be used to delimit the species therefore, classificatory for the taxa as no from Terminalia avicennioides that is woolly hairy significant difference was observed in the leaf only on the abaxial surface. This however, can length, leaf width and petiole length in Terminalia enhance the understanding of the relationship mantaly and Anogeissus leiocarpus. This established existing among members of the family similarity enables us to be more informed about Combretaceae. Leaf stalk on the other hand can the intra – and intergeneric closeness that exist also be used to separate the eleven species critically among members of the family Combretaceae examined in this study. Among all the species, (Table 3). The result of the vegetative and Combretum dolichopetalum and Terminalia mantaly are reproductive morphology of members of the sub-sessile and this delineates the two species family Combretaceae revealed that vegetative from others studied in their respective genera, characters like leaf length, leaf width and useful in the identification and taxonomy of the reproductive characters like stamen length, style family generally. and stigma length, seed length and seed width had high factor loadings (Table 5). Data generated from both the quantitative 378 Akinsulire et al.: Vegetative and Reproductive Morphological Study

us Weak None Acute Entire Coarse Genus Genus Obtuse Scandent Glabrous Glabrous xerophytic shrub/liana Quisqualis Mesophytic/ Suffrutescent Q. indica Greyish brown Obovate/oblong Eucamptodromo

grey

Tree

Erect mous Acute Acute Entire

Coarse Genus Genus Woody Savanna/ Pubescent Pubescent Numerous A. leiocarpus Anogeissus

forest border Dark brown/ brown/ Dark Eucamptodro Ovate/elliptic s

Tree Erect forest Acute Entire

Coarse Woody

Obovate

Savanna/ pubescent

Pubescent Numerous

T. T. avicennioides

Acute/obtuse

Woolly or velvety or velvety Woolly Dark brown/ greyDark brown/

Tree Erect None Acute Woody Obtuse Entire/ Obovate Glabrous Glabrous T. T. mantaly

Ashy greyAshy undulating Mesophytic

Slightly coarse Cladodromous Eucamptodromou

Terminalia Tree Erect mous None Acute Oval/ Entire region obtuse Coarse Acute/ Woody obovate Tropical Tropical Glabrous T. T. ivorensis Pubescent Dark brown Dark Genus Genus Eucamptodro

grey Tree Erect None Acute Acute Entire coarse region omous Slightly Woody Tropical Tropical Obovate T. T. superba Glabrous Glabrous Ashy Eucamptodr

Tree Erect mous None Entire brown Retuse Coarse Lobate Woody T. T. catapa Acute to Acute to Obovate Glabrous Tropical/ pubescent Grey/dark Glabrous / Ornamental Eucamptodro

s

Weak Entire Forest Coarse Elliptic Scandent Cordate/ acuminate Pubescent Pubescent Numerous shrub/liana Suffrutescent Cordate/lobate C. dolichopetalum C. Grey/dark brown Eucamptodromou us

Weak None Acute Entire Forest

Coarse

Cordate glabrous Obovate Scandent

Pubescent pubescent; pubescent; Young Young leaf

mature leaf

shrub/liana Green/grey

C. racemosum

Suffrutescent

Eucamptodromo Combretum Genus Genus ous Weak Acute Entire Forest Coarse C. zenkeri C. Cordate Obovate Scandent Pubescent Pubescent Numerous shrub/liana Green/grey Suffrutescent

Eucamptodrom

mous Weak None Entire Forest Coarse Acute/ Acute/ cuneate Obovate Scandent Glabrous Glabrous acuminate shrub/liana Green/grey C. platypterumC. Suffrutescent Eucamptodro

Habit Genus surface Species Habitat Venation Venation Leaf base Leaf apex Leaf shape Stem colour Leaf margin Leaf abaxial Stem surface Type ofType stem Petiole surface Petiole Nature of stem Hairs (abaxial) Characters Table 1: Qualitative Vegetative Morphological Characters of Vegetative 1: Qualitative Species of Eleven Table Combretaceae Akinsulire et al.: Vegetative and Reproductive Morphological Study 379

indica Valvate Blackish rounded Whitish/ Whitish/ Greenish Glabrous Glabrous ellipsoidal /reddish/ Estipulate Racemose Ellipsoidal Quisqualis Green/acute Actinomorphic Softly pubescent Softly Whitish/purplish

acute brown elliptic

Absent Valvate Densely globbose Greenish Glabrous Glabrous Orbicular Estipulate Pubescent Brownish/ Brownish/ leiocarpus Anogeissus Actinomorphic Yellow/reddish Yellow/reddish Cream coloured/

acute

Absent

Valvate Axillary Whitish

Glabrous Glabrous Estipulate

Dark brown Dark Terminalia Terminalia Pale brown/ Pale spike/raceme spindle shaped avicennioides Actinomorphic Oblong/elliptic Softly pubescent Cream coloured/

c Cluster Absent

Valvate

mantaly Greenish Glabrous Glabrous Glabrous Crimson/ Estipulate

Brownish/ Brownish/ Yellow/red

Terminalia Terminalia narrow ovate Ovate/elliptic Actinomorphi whitish/ acute

ovoid Cream Absent Slightly Valvate Oblong Greenish Glabrous Glabrous ivorensis Estipulate pubescent Dark brown Dark Terminalia Terminalia Pale brown/ Pale Axillary spike Axillary Actinomorphic coloured/ acute

ovoid Cream Absent Valvate Densely superba Greenish Glabrous Glabrous Estipulate pubescent Palebrown/ Palebrown/ Dark brown Dark Terminalia Terminalia Axillary spike Axillary Actinomorphic coloured/ acute Oblong/ elliptic

c

acute Spike ovoid Ovoid Absent catapa Valvate Glabrous Glabrous Glabrous Estipulate coloured/ Greenish/ Brownish/ Brownish/ Yellow/red Terminalia Terminalia dark purplish White/cream White/cream Actinomorphi

pinkish Valvate Glabrous Glabrous Estipulate Pubescent Greenish/ ntamerous Pale brown Pale Yellow/light Yellow/light Green/acute Combretum Axillary spike Axillary Light yellow/ Light yellow/ greenish/acute spindle-shaped Actinomorphic Tetramerous/pe dolichopetalum

pinkish Valvate

Glabrous Glabrous Estipulate coloured/

Pubescent Greenish/

Pale brown Pale Red/cream entamerous racemosum Green/acute Combretum Axillary spike Axillary

spindle-shaped Actinomorphic Tetramerous/p Whitish/ cream Whitish/ coloured/ acute acute cream Cream Valvate zenkeri Densely coloured Whitish/ Whitish/ Glabrous Estipulate coloured/ pubescent Pubescent Greenish/ brownish/ brownish/ Pale brown Pale Creamson/

Combretum Pentamerous

whitish/ acute spindle-shaped

Globbose head Globbose Actinomorphic

acute acute cream Valvate Whitish/ Whitish/ Glabrous Glabrous Estipulate coloured/ coloured/ Pubescent Pale yellow Pale Pink/cream Pink/cream Pink/white/ Pink/white/ Tetramerous Combretum Axillary spike Axillary platypterum spindle-shaped Deep pink/red Deep Actinomorphic

Species Stipule Pedicel surface Sepal colour/ apex shape Corolla colour/apex shape Style surface Filament surface Floral aestivation Floral symmetry Inflorescence Unripe fruit colour Ripe fruit colour Fruit shape Seed colur/shape Character Table 2: Qualitative Reproductive Morphological Characters of Species Combretaceae 2: Qualitative Reproductive Table 380 Akinsulire et al.: Vegetative and Reproductive Morphological Study The taxonomic implication is that vegetative and characters studied except those taxon-specific reproductive morpho-characters are important in characters peculiar to C. dolichopetalum. The second separating the species of the family main cluster also has the genus Terminalia on the Combretaceae. Reproductive characters being other side of it where T. catapa, T. superba, T. more important and are therefore the characters ivorensis and T. avicennioides show great closeness responsible for the morphological variations (Figure 2). This agrees with the intrageneric observed among the eleven species of relationship and closeness previously enumerated Combretaceae studied. The dendogram (Figures 1 by Hutchinson and Dalziel (1958). Within the and 2) revealed the clustering of the taxa based on genus Terminalia, T. mantaly is the only species their generic delimitations with slight overlap. It showing little morphological dissimilarity to other clearly shows the intra-and-intergeneric members of the genus because it is an introduced morphological relationships that exist among and mesophytic species not recorded nor members of the family Combretaceae. In the described by Hutchinson and Dalziel (1958). Its genus Combretum, C. dolichopetalum is the only distinctive features include undulating leaf species in both figures distinct from other margin, ovate or elliptic fruit shape and sub-sessile members of the genus due to the fact that it is the leaf. Anogeissus leiocarpus occupies the first main only sub-sessile taxon with elliptic leaf, cordate or cluster occurring clearly delineated from all other occasionally acuminate leaf apex, lobate base and members of the family Combretaceae (Figure 1). light yellow or occasional light-greenish petal. C. However, the monotypic genus-Quisqualis, may racemosum, C. platypterum and C. zenkeri are all at the have shared some generic relationship with the same level (Figure 2) because they all have in genus Combretum but clearly distant from the genus common all the qualitative morphological Terminalia (Figure 1).

Table 3: Quantitative Vegetative Morphological Characters of Eleven Species of Combretaceae with Duncan Mean Separation.

Attributes Leaf length Leaf width Petiole length Genus Species (cm) (cm) (cm) C. platypterum 13.61±0.26e 5.98±0.17cd 1.45±0.23de

d e ef Genus Combretum C. zenkeri 12.03±0.54 7.17±0.39 1.67±0.07

C. racemosum 12.12±0.23d 5.54±0.05c 0.82±0.03b

C. dolichopetalum 6.99±0.19b 4.08±0.10b 0.33±0.02a

T. catapa 22.28±1.07g 13.17±0.54g 1.78±0.06f

Genus Terminalia T. superba 17.86±0.46f 8.98±0.26f 4.18±0.16h

c b cd T. ivorensis 10.61±0.22 4.55±0.12 1.19±0.04 T. mantaly 2.69±0.14a 1.39±0.08a 0.19±0.01a

T. avicennioides 14.67±0.41e 7.75±0.19e 3.26±0.09g

Genus Anogeissus A. leiocarpus 2.31±0.10a 1.45±0.09a 0.20±0.16a

Genus Quisqualis Q. indica 12.14±0.26d 6.32±0.15d 1.02±0.03bc

*means with the same alphabet along the same column are not significantly different Akinsulire et al.: Vegetative and Reproductive Morphological Study 381

a a a a a a a a a a a 1.00±0.00 1.00±0.00 1.00±0.00 1.00±0.00 1.00±0.00 1.00±0.00 1.00±0.00 1.00±0.00 1.00±0.00 1.00±0.00 1.00±0.00 Seed number e f cd a a d bc b bcd bc bc

0.14±0.00 0.12±0.01 0.74±0.02 0.36±0.01 0.30±0.00 0.28±0.01 5.11±0.05 0.34±0.01 0.33±0.01 0.28±0.01 0.30±0.00 Seed width (cm) e c g f e e e a b d d

1.07±0.02 0.43±0.01 0.66±0.01 0.76±0.02 1.98±0.06 1.55±0.03 1.09±0.03 1.08±0.02 1.05±0.01 0.92±0.02 0.96±0.02 Seed length (cm) c e c a b d - - - - -

0.97±0.04 2.50±0.03 5.28±0.08 2.60±0.08 1.77±0.04 3.66±0.11 Fruit width (cm)

c a a d d b - - - - - 1.91±0.05 4.75±0.21 1.79±0.01 6.52±0.11 6.42±0.08 Fruit length (cm)

e c a b d ------3.32±0.03 2.81±0.03 0.59±0.01 1.65±0.01 1.93±0.03 Fruit diameter(cm) 2.53±0.03

e c d b b b b b b b a 3.87±0.11 0.47±0.02 0.61±0.02 0.46±0.01 0.58±0.01 0.51±0.12 0.54±0.01 0.59±0.02 0.26±0.00 7.02±0.07 Style and stigma (cm) 1.57±0.03 e f c d b b b a b b b

1.87±0.04 0.46±0.01 0.44±0.01 2.71±0.02 0.49±0.01 0.33±0.00 0.46±0.01 0.49±0.01 0.44±0.01 5.11±0.05 1.40±0.02 Stamen Stamen length (cm) c b d a a ------

2.0280±0.10 1.9280±0.04 0.2600±0.04 0.2000±0.00 Petal length Petal (cm) 0.2740±0.01 *means with the same alphabet along column are not significantly different cde g ef f bc h bcd def a ab ab

0.25±0.01 1.650.08± 0.26±0.01 0.33±0.01 0.28±0.01 0.15±0.00 0.64±0.01 0.20±0.00 0.35±0.01 Sepal length (cm) 0.37±0.02 0.19±0.01

c c c c f e a a d a b Pedicel Pedicel length (cm) 0.42±0.01 0.20±0.00 0.24±0.10 0.56±0.03 0.44±0.01 0.48±0.02 0.18±0.01 0.44±0.01 1.85±0.06 0.92±0.02 0.31±0.02

Species Combretum platypterum Combretum zenkeri Combretum racemosum Combretum dolichopetalum Terminalia catapa Terminalia superb a Terminalia ivorensis Terminalia mantaly Terminalia avicennioides Anogeissus leiocarpus Quisqualis indica Table 4: Table Separation Mean Duncan with Combretaceae of Species Eleven of Characters Morphological Reproductive Quantitative 382 Akinsulire et al.: Vegetative and Reproductive Morphological Study The principal component analysis scattered reproductive morphology such as sepal colour diagram of the species based on combined and shape of sepal apex, ripe fruit colour and seed quantitative vegetative and reproductive colour, hence their monophyletic origin. morphological characters reveals the similarities that exist between the genera Terminalia and This study therefore shows that the combination Anogeissus (Figure 3). Terminalia mantaly is of both vegetative and reproductive morphologically related to Anogeissus leiocarpus in morphological characters can be used successfully the family because of the similarities in their leaf in delimiting the species into genera and in the lengths, leaf widths and petiole lengths, stamen understanding of the pattern of inter- and-intra- lengths, style and stigma lengths, seed numbers as generic similarities and differences in the family. well as the similarities in their qualitative

Species of the family Combretaceae

Figure 1: Dendogram of Combretaceae Species Based on Quantitative Reproductive Morphological Characters Tm-Terminalia mantaly, Qi- Quisqualis indica, Al- Anogeissus leiocarpus, Cz- Combretum zenkeri, Cd –Combretum dolichopetalum, Tc –Terminalia catapa, Ts-Terminalia superba, Ti-Terminalia ivorensis, Cp – Combretum platypterum, Ta-Terminalia avicennioides, Cr - Combretum racemosum

Table 5: Principal Components Analysis (PCA) Factor Loadings of Some Important Quantitative Vegetative and Reproductive Morphological Characters of Eleven Species of Combretaceae Characters PCA1 PCA2 Leaf length 0.91 - Leaf width 0.89 - Stamen length - 0.90 Style and stigma - 0.85 Seed length 0.88 Seed width - 0.81 Akinsulire et al.: Vegetative and Reproductive Morphological Study 383

1 2 3 4 5 6 7 8 9 10 11

Species of the family Combretaceae Figure 2: Dendogram of Combretaceae Species Based on Combined Quantitative Vegetative and Reproductive Morphological Characters Qi- Quisqualis indica, Al- Anogeissus leiocarpus, Cd –Combretum dolichopetalum, Cz- Combretum zenkeri, Cr-Combretum racemosum, Cp –Combretum platypterum, Tc –Terminalia catapa, Ti-Terminalia ivorensis, Ta - Terminalia avicennioides, Tm-Terminalia mantaly, TS – Terminalia superba.

Figure 3: Principle Components Analysis (scattered diagram) of eleven species of Combretaceae Based on Combined Quantitative Vegetative and Reproductive Morphological Characters. Qi - Quisqualis indica, Al - Anogeissus leiocarpus, Cd– Combretum dolichopetalum, Cz - Combretum zenkeri, Cr - Combretum racemosum, Cp – Combretum platypterum, Tc –Terminalia catapa, Ti - Terminalia ivorensis, Ta -Terminalia avicennioides, Tm - Terminalia mantaly, TS - Terminalia superba. 384 Akinsulire et al.: Vegetative and Reproductive Morphological Study CONCLUSION classification, standardization and subsequent The generic, classificatory and diagnostic features identification of members of the family obtained in the study will serve as basis for proper Combretaceae

0.07cm a b 0.30cm

c 0.82cm d 1.00cm Plates (1a – d): Morphological Study of Combretum platypterum. (a): Habit of C. platypterum (b): spike-like raceme inflorescence of C. platypterum (c): Fruits of C. platypterum (d): Seeds of C. platypterum

0.15cm 2.00cm

0.75cm 0.67cm

Plates (2a - d): Morphological Study of Combretum zenkeri (a): Habit of C. zenkeri (b): inflorescence (c): Fruits of C. zenkeri (d): Seeds of C. zenkeri Akinsulire et al.: Vegetative and Reproductive Morphological Study 385

0.04cm a b 0.15cm

c 0.56cm d 0.50cm

Plates (Plates 3a - d): Morphological Study of Combretum racemosum (a): Habit of C. racemosum (b): Spike inflorescence (c): Fruits of C. racemosum (d): Seeds of C. racemosum

0.22cm a b 0.60cm

c 0.72cm d 1.00cm

Plates (4a - d) Morphological Study of Combretum dolichopetalum (a): Habit of C. dolichopetalum (b): inflorescence of C. dolichopetalum (c): Fruits of C. dolichopetalum (d): Seeds of C. dolichopetalum 386 Akinsulire et al.: Vegetative and Reproductive Morphological Study

1.10cm a 0.03cm b

c 0.48cm d 0.08cm

Plates (5a - d): Morphological Study of Terminalia catapa (a): Habit of T. catapa (b): Spike inflorescence (c): Fruits T. catapa (d): Seeds of T. catapa

a 0.03cm b 0.95cm

c 0.86cm d 0.94cm Plates (6a - d): Morphological Study Terminalia superba (a): Habit of T. superba (b): Spike inflorescence and Fruit of T. superba (c) and (d): Dried Fruits or T. superba Akinsulire et al.: Vegetative and Reproductive Morphological Study 387

a 0.32cm 0.03cm b

0.95cm c d 0.34cm Plates (7a - d): Morphological Study of Terminalia ivorensis (a): Habit of T. ivorensis (b): Inflorescence (c): Dried Fruits of T. ivorensis (d): Fruits of T. Ivorensi

0.07cm a b 1.53cm

c 0.58cm d 1.30cm

Plates (8a - d): Morphological Study of Terminalia mantaly (a): Habit of T. mantaly (b): Spike inflorescence (c): Fruits of T. mantaly (d): Seeds of T. mantaly 388 Akinsulire et al.: Vegetative and Reproductive Morphological Study

a 0.05cm b 1.20cm

c dd 0.25cm 0.30cm

Plates (9a - d): Morphological Study of Terminalia avicennioides (a): Habit of T. avicennioides (b): Spike-like raceme inflorescence (c) and (d): Fruits of T. avicennioides

a 0.20cm b 1.30cm

c d 0.92cm 1.01cm

Plate (10a - d): Morphological Study of Anogeissus leiocarpus (a): Habit of A. leiocarpus (b): Inflorescence (c): Fruits of A. leiocarpus (d): Seeds of A. leiocarpus Akinsulire et al.: Vegetative and Reproductive Morphological Study 389

a 0.03cm b 0.30cm

1.10cm c d 0.83cm

Plate (11a - d): Morphological Study of Quisqualis indica (a): Habit of Q. indica (b): Racemose inflorescence of Q. indica (c): Fruits of Q. indica (d): Seeds of Q. indica

ACKNOWLEDGEMENT Africanae (I) combretum. Leipzig: W. We appreciate the former curator of IFE Engelmann. Herbarium, Mr. Ibhanesebhor, as well as Mr. Gill, L. S., (1988). Taxonomy of Flowering Plants. Bernard Omomoh of the Department of Africana-FEP Publishers Ltd., Ibadan, Forestry and Wood Technology, Federal Nigeria. 337p. University of Technology, Akure. Hutchinson, J. and Dalziel, J. M. (1958). Flora of West Tropical Africa. Crown Agents for AUTHOR'S CONTRIBUTIONS Overseas Government and 'Author 1' designed the study, wrote the first and Administration Nill Bank London Vol. 1. second draft of the manuscript and joined Author pp 2 in performing the statistical analysis; 'Author 2' Keay, R. W. J. (1989). Trees of Nigerian. Clarendon performed the statistical analysis together with Press, Oxford, UK. 300p Author 1; 'Author 3' wrote the protocol, managed Mabberley, D. J. (2008). The Plant Book: A portable and previewed the analysis of the study while dictionary of the vascular plants, 3rd edn. 'Author 4' collected plant accessions from Cambridge University Press. 1040p different parts of southern Nigeria. All authors Smith, C. and Ashton, P. A. (2006). Distinction read and approved the final manuscript. between the sedges Carex vulpina L. and C.otrubae Podp. and the potential for REFERENCES identification of hybrids. Watsonia, 26: 15 Adedeji, O. A. and Faluyi, J.O. (2006). – 25. Morphological, agrobotanical and Stace, C.A. (2007). Combretaceae. In: kubitzki, K., reproductive studies in 35 acessions of ed. The families and genera of vascular Plants Panicum maximum. Jacq. in Southern 9. Berlin: spinger Verlag, 67-82. Nigeria. Research Journal of Botany, 1(2): 64 – 74. U.S.A Engler, A. and Diels, L. (1899). Monographieen Afrikanischer Pflanzen-Familien und- Gattungan, 111. Combretaceae