Genus Descriptions

Convolvulus

Accepted name/Authority/Place of publication:

Convolvulus L. Sp. Pl. 1: 153 (1753)

Contributors:
Author:
Mark Carine
Distribution:

The genus is essentially temperate in its distribution. The most important centres of diversity are to be found in the Mediterranean (including Macaronesia), East Africa, Central Asia and Arabia. Southern Africa, temperate south America and Australasia also harbour significant numbers of species. There are only three species in north America although Calystegia, that constitutes a monophyletic group nested within Convolvulus, is diverse there. Convolvulus arvensis is a widely distributed weed species.

Editor:
Esmond Er
Flowers:
Sepals 5, quincuncial, usually unequal, the middle sepal often asymmetric, the exposed half resembling the outer sepals and the enclosed half resembling the inner sepals. Corolla funnel-form or rarely campanulate; margin entire or lobed, rarely ±fimbriate; limb pink, white, purple, blue or rarely yellow, the centre often differently coloured, the throat occasionally with dark marks; usually glabrous except for the midpetaline bands that are pubescent in the upper half in most species. Stamens included, often unequal. Filaments dilated at the base, filiform above, glabrous or with sessile or stalked glands in the dilated part. Anthers +/- equal, oblong to sagitate, rarely broadly oblong, dehiscing longitudinally. Ovary ovoid, conical or globular, entire or lobed, glabrous or hairy, sometimes densely so. Style one, slender, glabrous or hairy. Stigmas two, filiform or cylindrical.
Fruits:
Capsules dehiscing loculicidally or irregularly.
Habit:
Annual or perennial, erect, prostrate or climbing herbs, sometimes lignified at the base, woody lianas and erect shrubs, the latter sometimes spiny. Pubescent or not, the hairs unbranched.
Inflorescences:
Axillary or terminal; flowers in one to many-flowered cymes, rarely arranged in a compound thyrsi, sometimes apparently solitary axillary. Bracteoles usually small and filiform but in compact inflorescences sometimes leafy, ovate or lanceolate.
Infrageneric Characters:

Carine et al (2004) identified two major groupings within
the genus. The first comprises perennial, mostly erect plants which have
sessile, always entire leaves. Chromosome numbers for this group are 30, 36 and
60. The second clade includes Calystegia and comprises species that have
distinctly petiolate leaves that are sometimes divided. The habit is variable
but typically, trailing or climbing. Chromosome numbers reported for this clade
are 20, 22, 24, and 28 (or multiples thereof). A project is currently underway
to expand the sampling of Carine et al (2004) more widely across the genus to
better understand morphological evolution and the classification of the genus.

Leaves:
Sessile or petiolate, margins entire to deeply lobed, sometimes highly variable in shape within an individual or a species.
Number of Species:
200
Pollen:
Elliposidal, trciolpate.
References:

Carine, M. A., Francisco-Ortega, J., Santos-Guerra, A. and Russell. S. J. (2004). Relationships of island and continental floras: molecular evidence for multiple colonisations into Macaronesia and subsequent back-colonisation of the continent in Convolvulus L. American Journal of Botany 91: 1070-1085.

Sa’ad, F. 1967. The Convolvulus species of the Canary Islands, the Mediterranean region and the near and Middle East. Medelingen van het Botanisch Museum en Herbarium van de Rijksuniversiteit te Utrecht 281: 1–288.

Seeds:
1-4, surface smooth, tuberculate, ridged or hairy.
Synonyms:

Rhodorhiza Webb in Bot. Reg.. Misc. 69 (1841)

Tribe:
CONVOLVULEAE
Type Species:

Convolvulus arvensis L.

Mon, 2012-03-26 02:02 -- Esmond
Seddera

Accepted name/Authority/Place of publication:

Seddera Hochst., Flora 27 [Bes. Beil.]: 7, plate 5, (1844).

Contributors:
Author:
Sebsebe Demissew & R. Mill
Distribution:

Mainland Africa, Madagascar, Arabia and the Indian subcontinent.

Editor:
George Staples, Esmond Er
Flowers:
Sepals 5, obtuse or acute at the apex, subequal or the outer ones larger than the inner. Corolla commonly white, rarely yellow or pink to blue, funnel-shaped with shallowly 5-lobed limb; mid-petaline areas hairy throughout or at least at the tips. Stamens 5, ± equal, inserted at the base and often with appendages; anthers oblong; pollen smooth. Disc absent or small. Ovary 2-locular, with 2 ovules in each locule, hairy all over or only above; styles 2, usually divided to the base, sometimes apparently simple; stigmas ± peltate or club-shaped to ellipsoid.
Fruits:
Capsule 4-valved or fruit sometimes indehiscent.
Habit:
Small suberect or prostrate subshrubs or shrubs or perennial herbs.
Inflorescences:
Flowers axillary or terminal, sessile or pedunculate, solitary or aggregated to form dense clusters of spikes, cymes, racemes or panicles. Bracts and bracteoles small, sometimes caducous.
Infrageneric Characters:

Infrageneric taxa have occasionally
been recognised within the genus. Roberty (Candollea
14: 29, 1953) described subgen. Schitzanthoseddera
[sic] for two species with deeply lobed, infundibular corollas, namely S.
schizantha Hall. f. and S. welwitschii Hall. f. The latter name is
here reduced to synonymy under S. suffruticosa var. suffruticosa.
Seddera schizantha was later
raised to generic rank as Schizanthoseddera (Roberty) Roberty in Boissiera
10: 151 (1964). The latter name has been overlooked by Brummitt et al. (1992)
although it is listed as a validly published name in Index Nominum
Genericorum (ING) and the International Plant Names Index (IPNI). We
here once again treat Schizanthoseddera as
part of the genus Seddera.

Leaves:
Leaves with variable shape and entire margins, commonly with medifixed hairs.
Number of Species:
31
Other information:
Two sections are recognized 1. Styles two, free to the base or almost so, each with its own stigma. Sect. Seddera (28 species). 1. Styles apparently simple, diverging into two discrete stigmatic arms only at the apex. Sect. Socotroseddera (3 species).
Phylogeny:

Seddera has generally been placed in tribe Cresseae of Convolvulaceae. Within that tribe it is genetically closest to the genera of (former) Hildebrandtieae, i.e. Hildebrandtia and Cladostigma (Stefanović et al., 2002). These two tribes have been considered very closely related, with a monophyletic Hildebrandtieae nested within a paraphyletic Cresseae (Sebsebe Demissew & Austin, 1996; Stefanović et al., 2002). In the most recent analysis (Stefanović et al., 2003) these two tribes were united.

Publication:

Sebsebe Demissew &
R. Mill, Kew Bull. 64: 197–233 (2009).

Seeds:
Seeds ovoid to trigonous, black or dark brown, glabrous.
Synonyms:

Seddera subgenus Schizanthoseddera Roberty Candollea 14: 29 (1953); Schizanthoseddera (Roberty) Roberty in Boissiera 10: 151 (1964).

Type: S. schizantha Hallier f.

Sedderopsis Roberty in Candollea 14: 29 (1953).

Type: Sedderopsis capensis (E. Meyer ex Choisy) Roberty (Seddera capensis E. Meyer ex Choisy).

Tribe:
Cresseae
Type Species:

Type: Seddera virgata Hochst. & Steud. [lectotype chosen by Meeuse, Bothalia 6: 662, 1958].

Fri, 2011-11-25 03:42 -- Esmond
Hildebrandtia

Accepted name/Authority/Place of publication:

Hildebrandtia Vatke in Sitzungsber. Ges. Naturf. Freunde Berlin 1876a: 7 (1876) & in Monatsber. Konigl. Preuss. Akad. Wiss. Berlin 1876: 864 (1877).

Contributors:
Author:
Sebsebe Demissew, M. Carine and Javier
Countries:
Ethiopia
Somalia
Kenya
Tanzania
Uganda
Madagascar
Arabia
Distribution:

Known from eastern Africa (Ethiopia, Somalia, Kenya, Tanzania and Uganda) and Arabia (8 species), Madagascar (2 species).

Editor:
Esmond Er
Flowers:
Flowers unisexual, dioecious, solitary or fasciculate 2--4 together in short pubescent lateral shoots. Male flowers subsessile to pedicellate. Sepals 4--5, subequal or unequal, the two outer ones usually slightly
Fruits:
Fruits enclosed in accrescent, chartaceous calyx; indehiscent, an utricle or utricle-like (in Madagascar species), 1- or 2-locular, ovoid to ellipsoid, mostly chartaceous. Fruit enclosed in accrescent calyx with two or three outer segments larger than the inner two, sometimes the outer segments fused; the inner two usually remaining minute or much smaller than the outer segments, glabrous. Capsule ovoid to globose, 4-valved, glabrous.
Habit:
Shrubs; stems woody, erect, scandent or prostrate, shoots pubescent.
Leaves:
Leaves petiolate, simple, entire, chartaceous to coriaceous, base attenuate, acute, or obtuse, apex attenuate to obtuse, pinnately veined, densely appressed pubescent to glabrous. Inflorescences axillary or terminal on lateral branches, umbelliform to paniculate-thyrsiform, composed of cymose units; peduncle hidden among flowers or quite long; bracts present, deciduous or persistent. Leaves solitary or fasciculate, 2--5 together on short pubescent shoots; lamina glabrous, adpressed silvery pubescent to villous on both sides.
Number of Species:
10
Publication:

Sebsebe Demisew Kew Bulletin, Vol. 51, No. 3 (1996), pp.
525-541

Seeds:
Seeds 1–4, Seeds trigonous-ovoid, brown to dark brown, reticulate.
Synonyms:

Pterochlamys Roberty in Candollea 14: 23 (1952). Type species: Pterochlamys somalensis (Engl.) Roberty (= Hildebrandtia somalensis Engl. ex Peter).

Sabaudiella Chiov. in Nuovo Giorn. Bot. Ital., n.s. 36: 366 (1929); Verdcourt in Kew Bull. 17(2): 229 (1963). Type species: Sabaudiella aloysii Chiov.

Tribe:
Cresseae
Type Species:

Hildebrandtia africana Vatke in Sitzungsber. Ges. Naturf. Freunde Berlin 1876: 7 (1876a); in J. Bot. 14: 313 (1876b) & in Monatsber. Konig. Preuss. Akad. Wiss. Berlin 1876: 865 (1877).

Thu, 2011-11-24 05:30 -- Esmond
Nephrophyllum

Accepted name/Authority/Place of publication:

NEPHROPHYLLUM A. Rich., Tent. Fl. Abyss. 277 (1851).

Author:
Sebsebe Demissew, M. Carine & Javier Luna
Countries:
Ethiopia
Eritrea
Distribution:

Known from Ethiopia and Eritrea (only one species). map

Ecology:

Heavily
grazed pastures, open ground, between crevices of bare rocks on steep slopes,
1650-2700 m altitude.

Editor:
<p>George</p>
Flowers:
Flower solitary, axillary, bracts ovate, c. 1 x 1 mm. Pedicel 1 mm long on flowering specimens, 5- 10 mm long when fruiting, elongating to 27 mm in fruit. Calyx membranous, 5-lobed, less than 0-5 mm long, forming a tube. Corolla white to pink, 3-6 mm long, campanulate, 5-lobed, lobes shallow and unclear, puberulous on mid-petaline areas. Stamens 5, inserted in three series, filaments unequal, the ovoid anthers glabrous. Ovary 1-locular with 2-4 ovules; styles two, unequal, attached terminally on ovary, 1.2-2 mm long. Stigmas club-shaped.
Fruits:
Fruit a utricle, developing underground with a pedicel to 27 mm long, one-lobed, glabrous, whitish.
Habit:
Herb; annual or perennial; Stem prostrate, rooting at the nodes, glabrous to puberulous.
Leaves:
Leaves petiolate; Leaf blade reniform to suborbicular on outline, glabrous to puberulous, retuse at the apex, cordate at the base.
Number of Species:
1
Publication:

Sebsebe Demisew & D. Austin, Kew Bulletin 50: 103-108 (1995).

References:

Sebsebe Demissew. 2006. Flora of Ethiopia and Eritrea 5: 161-231.

Sebsebe Demissew & D.F. Austin. 1995. The genus Nephrophyllum (Convolvulaceae, tribe Dichondreae) in Ethiopia. Kew Bull. 50: 103-108.

Seeds:
Seed 1, brown, 2-3 x 2.5 mm, obovoid, glabrous.
Synonyms:

Hygrocharis Hochst., Pl. Schimp. exs. Abyss. sect. II: 572; ex Hallier f., Bot. Jahrb. Syst. 16: 569 (1893), non Hygrocharis Nees, Mart. Fl. Bras. 2(1): 147 adnot. (1842).

Tribe:
Dichondreae
Type Species:

Nephrophyllum abyssinicum Hochst. ex A. Rich. Tent. Fl. Abyss. 2: 77, t. 76 (1851); Engler, Hochgebirgs fl. Trop. Afr. 345 (1892).

Tue, 2011-08-16 13:13 -- George Staples
Jacquemontia

Accepted name/Authority/Place of publication:

Jacquemontia Choisy, Mémoires de la Société de Physique et d’Histoire Naturelle de Genève 6:476. 1834, Voyage aux Indes Orientales t. 10. 1837.

Author:
Choisy; Robertson
Commentary:

Phylogeny is still undefined. Morphological studies suggested the relation with Convolvulae tribe. Stefanovic (2003) showed that the position within the family is uncertain, but was more close to the group with branched styles, as Bonamia and Evolvulus. Suggesting a new tribe Jacquemontieae.

Distribution:

Mostly Neotropical with few species occurring intropical Africa and Asia, and Australia.

Editor:
Maria Teresa Buril
Flowers:
corolla funnelform, campanulate, rotate, or rarely salverform, entire to deeply 5-lobed, glabrous or sparsely pubescent, frequently blue or white, rarely pink; stamens equal or unequal, flattened on base; ovaries 2-locular, each locule with 2 ovules, the disk small or absent, style 1, unbranched, stigmas 2-lobed, lobe shape variable, usually ellipsoid, dorsiventrally flattened.
Fruits:
Capsule 8-valvar, sepals sometimes acrescent.
Habit:
Perennial or annual vines, with climbing, decumbent, prostrate, rarely suffrutescent stems; glabrescent to more frequently densely pubescent, trichomes 3- to 8-armed, stellate, the arms equal or unequal, glandular trichomes sometimes present.
Inflorescences:
Inflorescences 1-multi-flowered, cymes lax to congested; bracts usually present. Sepals 5, equal or unequal, usually dimorphic with the 2 outer, middle, and 2 inner sepals presenting distinct morphologies, variable in shape.
Leaves:
Leaves alternate, rarely sessile, blades variable, linear, elliptic, orbicular, frequently ovate, apex usually acuminate, basis cordate or rounded, rarely cuneate, margins entire or slightly repand and undulate.
Number of Species:
120
Pollen:
Pollen smooth, with micro spines, 3 or aggrego-colpate.
Publication:

Choisy, Mémoires de la Société de Physique et d’Histoire Naturelle de Genève 6: 476. 1834, Voyage aux Indes Orientales t. 10. 1837.

Robertson, K.R. 1971. A Revision of the Genus Jacquemontia (Convolvulaceae) in North and
Central America and the West Indies. PhD thesis.

Seeds:
Seeds usually 4, glabrous, trigonous if all 4 are formed, areolate and often verrucate, ruminate, or striate, the outer 2 margins often with a small wing or crest; embryos longiplicate or lati- longiplicate.
Synonyms:

Thyella Rafinesque, FloraTelluriana 4: 84. 1838. Lectotype: T.tamnifolia (Linnaeus) Rafinesque = J.tamnifolia (Linnaeus) Grisebach; selected by House (1906)

Montejacquia G. Roberty, Candollea 14: 33. 1952. No type designated

Jacquemontia subg. EujacquemontiaG. Roberty, Candollea 14: 32. 1952, nom. illegit.

Jacquemontia subg. SchizojacquemontiaG. Roberty, Candollea 14: 33. 1952

Schizojacquemontia G. Roberty, Boissiera 10: 149. 1964. Type: S.parviflora (Vahl) G. Roberty = J.paniculata (Burman f.) Hallier f

Tribe:
Convolvuleae
Type Species:

Lectotype species: Convolvulus pentanthosJacquin = J. pentanthos (Jacquin) G. Don.

Tue, 2011-08-16 12:57 -- Esmond
Hyalocystis

Accepted name/Authority/Place of publication:

Hyalocystis Hallier, f. Annuario del Reale Istituto Botanico di Roma 7: 227 (1898)

Author:
Sebsebe Demissew, Mats Thulin
Countries:
Ethiopia
Somalia
Distribution:

Eastern Africa

Editor:
Genus page and pollen data: Ana Simoes
Flowers:
Sepals rather thin and scarious, the outer 3 larger than the inner 2. Corolla reddish, pinkish or yellowish with darker centre, densely pilose outside. Ovary 1-celled, pilose, with 4 ovules; style filliform; stigmas 2, globose.
Fruits:
Capsule globose, indehiscent, membranous, 1-seeded, pubescent.
Habit:
Prostrate perennial herbs, with indumentum of glandular hairs; stems rooting at the nodes.
Inflorescences:
Flowers 1-3 in axillary pedunculate bracteate cymes.
Leaves:
Leaves entire to distinctly palmately lobed, with spinose-dentate margins, petiolate.
Number of Species:
2
Pollen:
Smooth, 15-panto-aperturate.
Publication:

Thulin, M. (ed.), Flora of Somalia 3: 241. Kew (2006).

References:

Thulin, M. (ed.), Flora of Somalia 3: 241. Kew (2006).

Seeds:
Seed globose, hairy.
Tribe:
Merremieae
Type Species:

Hyalocystis viscosa Hallier f. Ann. Ist. Bot. Roma vii.: 228 (1898)

Tue, 2011-08-16 12:37 -- Esmond
Cladostigma

Accepted name/Authority/Place of publication:

Cladostigma Radlk. in Abh. Naturwiss. Vereine Bremen 8: 412 (1883)

Acknowledgements:
This species page was produced as part of the project 'Expanding the scope of African Digital Plant Resources' funded by the World Collections Programme.
Contributors:
Author:
Sebsebe Demissew
Countries:
Ethiopia
Eritrea
Kenya
Saudi Arabia
Somalia
Distribution:

Northeast and East Africa and Yemen. map

Ecology:

Bushland with Acacia on diverse soil types from 325 - 1850 m

Editor:
Javier A Luna, Mark A. Carine, Sebsebe Demissew
Flowers:
Flowers 5-merous. Male flowers: Sepals subequal. Corolla tubular, much longer than the sepals, 5-lobed, pubescent on the outside. Stamens 5, with filaments + equal in length. Rudimentary ovary with 2 styles, longer than the stamens, with U-shaped stigma branches. Female flowers: Sepals subequal, all accrescent, or sometimes unequal with three outer ones accrescent, and two remaining smaller. Corolla only slightly longer than the sepals, pubescent on the outside. Ovary with 2 styles divided to the base and with branched stigma; ovary 2-locular with 2 ovules in each locule, glabrous to pubescent at the apex. Staminodes 5, ? equal in length with the filaments dilated at the base, without anthers.
Fruits:
Fruit capsular, 4-valved, 1 - 2 seeded, enveloped by the fruiting accrescent sepals.
Habit:
Erect or climbing dioecious shrubs.
Inflorescences:
Male flowers on pedunculate inflorescences. Female flowers on pedunculate inflorescences or fasciculate.
Infrageneric Characters:

Important characters for distinguishing species within the genus include habit (erect versus scandent or climbing shrub), leaf shape and pubescence, sepal shape and size (both in flower and fruit), pubescence and articulation of the male flowers and relative lengths of the pistillode and corolla.

Leaves:
Leaves usually alternate, rarely fascicled, covered with medifixed hairs on both sides.
Number of Species:
3
Pollen:
Not recorded
Publication:

The Genus Cladostigma (Convolvulaceae). Kew Bulletin 51 (2): 405-411 (1996)

Seeds:
Seeds ovoid, trigonous, rugose.
Tribe:
Cresseae

Mon, 2011-08-08 04:13 -- Esmond
Xenostegia

Accepted name/Authority/Place of publication:

XENOSTEGIA D. F. Austin & Staples, Brittonia 32: 533. 1980

Contributors:
Author:
G.W. Staples
Commentary:

Long included in the polyphyletic genus Merremia, these 2 species are distinctive in terms of pollen apertures, seed germination, cotyledon shape, stigma micromorphology, and seed characters; in 1981 they were segregated as genus Xenostegia.

Distribution:

Tropical regions of Asia, Africa, Australia and the Pacific; introduced and naturalized on Puerto Rico in the Caribbean. map

Editor:
G. Staples & Esmond Er
Flowers:
Flower sepals oblong or oblong-ovate, subequal to unequal, acute or obtuse; inner 3 sepals narrower, apically tapering into slender points, all enlarged in fruit; corolla pale yellowish or whitish, often with a purplish centre, broadly funnelform or campanulate; stamens included, anthers not twisted at dehiscence; pollen globose, pantoporate, not spiny; pistil included, ovary 2-celled, 4-ovuled, style 1, filiform, stigmas 2-globular.
Fruits:
Capsule 4-valved, glabrous or pubescent apically.
Habit:
Perennial herbs; stems prostrate, tips twining.
Inflorescences:
Inflorescences axillary, cymose, 1- or 2-(or 3)-flowered.
Leaves:
Leaves petiolate, linear, oblong-linear, lanceolate-elliptic, or oblanceolate to spathulate, base hastate; basal lobes clasping stem, dentate or entire, apex acute to emarginate, mucronate, or tridentate.
Number of Species:
2
Phylogeny:

Xenostegia tridentata is extraordinarily variable, which has led to naming of many taxa based on seemingly distinctive morphotypes. In Africa 3 infraspecific taxa are recognized; in Asia all the variation is accommodated in a single polymorphic species. In contrast, X. medium is rather constant in its morphology and is easily distinguished from its congener by the enlarged outer sepals.

Pollen:
Pollen globose, pantoporate, not spiny.
Publication:

Flora of Thailand 10(3): 464-467. 2010.

References:

Austin & Staples, Brittonia 32: 533-536. 1980.

R.C. Fang & Staples in C.Y. Wu & P.H. Raven (eds.), Fl. China 16: 300. 1995.

Lejoly & Lisowski, Fragm. Flor. Geobot. 38: 379. 1993.

Seeds:
Seeds 1–4, ovoid-trigonous, brownish to black.
Synonyms:

Merremia sect. Halliera O'Donell, Lilloa 6: 472. 1941.

Tribe:
Merremieae
Type Species:

Xenostegia tridentata (L.) D.F. Austin & Staples.

Mon, 2011-07-18 02:25 -- Esmond
Operculina

Accepted name/Authority/Place of publication:

OPERCULINA Silva Manso, Enum. Subst. Bras. 16. 1836

Contributors:
Author:
G.W. Staples
Commentary:

Very close to the polyphyletic genus Merremia, from which it has been at times separated and at other times merged. The operculate fruit type is distinctive morphologically and the available molecular data suggest that Operculina is a distinct genus.

Common names and uses:
The roots of Operculina turpethum have been used since antiquity as a purgative drug (turbith root).
Distribution:

Tropics worldwide. map

Editor:
G. Staples & Esmond Er
Flowers:
Flowers axillary, solitary or in few-flowered cymes; bracts often foliose, deciduous; sepals often accrescent in fruit, margins becoming lacerate; corolla broadly funnelform, campanulate or nearly salverform, glabrous or midpetaline bands pubescent outside, limb often 10-pleated, venation indistinct; stamens usually included, filaments basally adnate to corolla tube, filiform and free distally, anthers often spirally twisted at dehiscence; pollen 3-colpate, not spiny; pistil usually included; disc annular, ovary 2-celled, 4-ovuled, glabrous, style filiform, stigma 2-globose.
Fruits:
Fruit an operculate capsule, circumscissile at or above middle, upper portion lid-like, fleshy, separating from brittle endocarp, which shatters irregularly.
Habit:
Herbaceous or woody climbers; stems, peduncles, and petioles often winged.
Leaves:
Leaves petiolate, angular or palmate, base often cordate, margin entire.
Number of Species:
15
Pollen:
Pollen 3-colpate, not spiny.
Publication:

Flora of Thailand 10(3): 451. 2010.

References:

Ooststr., Blumea 3:361. 1939.

Ooststr., Fl. Males. I, 4: 454. 1953.

Staples & Austin, Brittonia 33: 591-596. 1981.

Verdcourt, Fl. Trop. E. Africa Convolvulaceae 61. 1963.

R.C. Fang & Staples in C.Y. Wu & P.H. Raven (eds.), Fl. China 16: 300. 1995.

Seeds:
Seeds 4 or fewer, trigonous or globular, glabrous or angles pilose.
Synonyms:

Turpithum Raf., Fl. Tellur. 4: 71. 1836.

Piptostegia Reichenbach, Nom. Bot. 113. 1841.

Ipomoea sect. Operculina (S. Manso) Griseb., Fl. Brit. W. Ind. 467. 1861.

Tribe:
Merremieae
Type Species:

Operculina turpethum (L.) S. Manso.

Mon, 2011-07-18 02:16 -- Esmond
Merremia

Accepted name/Authority/Place of publication:

MERREMIA Dennst. ex Endl., Gen. Pl. 1: 1403. 1841, nom. cons.

Contributors:
Author:
G.W. Staples
Commentary:

The geus Merremia is almost certainly polyphyletic, both on morphological grounds as well as the molecular data available to date (Stefanovic et al., 2002). Revisionary study now underway will elucidate generic delimitation and systematic relationships in tribe Merremieae.

Distribution:

Tropics and warm temperate zones. map

Editor:
G. Staples & Esmond Er
Flowers:
Flower sepals variable in shape, often markedly convex, nearly equal or outer 2 sepals smaller, persistent, often enlarged in fruit. Corolla funnelform or campanulate, often yellow or white, sometimes with a darker centre, usually glabrous or minutely hair-tufted at apex, rarely midpetaline bands sericeous outside, limb entire or 5-angled, veins often distinct in midpetaline bands; stamens included, often unequal, filaments dilated basally, filiform distally, anthers often spirally twisted; pollen 3–12-colpate or polyrugate, not spiny; pistil included, disc annular, ovary (imperfectly 2–)4-celled, 4-ovuled, style 1, filiform, stigmas 2-globular.
Fruits:
Capsule 1–4-celled, usually 4-valved or +/- irregularly dehiscing.
Habit:
Herbs or lianas, often twining, sometimes prostrate.
Inflorescences:
Inflorescences axillary, few- to many-flowered, cymose; bracts usually small.
Infrageneric Characters:

Often confused with Ipomoea, which has pantoporate, spiny pollen, straight anthers and very few species with yellow corollas, and Operculina, which consistently has a fruit with a circumscissile lid that detaches first, leaving a brittle endocarp that shatters irregularly, and many species with sericeous-hairy midpetaline bands on the corolla. The distribution of hairs on the corolla is taxonomically important in Merremia; this is most easily discerned on mature flower buds.

Leaves:
Leaves usually petiolate, rarely sessile, margin entire or dentate, lobed, or palmately or pedately lobed or compound.
Number of Species:
100
Pollen:
Pollen 3–12-colpate or polyrugate, not spiny.
Publication:

Flora of Thailand 10(3): 431-432. 2010.

References:

Ooststr., Blumea 3: 292. 1939.

Ooststr., Fl. Males. I, 4: 439. 1953.

Staples, Garden's Bull. Singapore 61: 483-522. 2010.

Songkhla & Khunwasi, Thai Forest Bull. (Bot.) 20: 30. 1993.

R.C. Fang & Staples in C.Y. Wu & P.H. Raven (eds.), Fl. China 16: 291. 1995.

Stefanovic, S. et al., Amer. J. Bot. 89: 1510-1522. 2002.

Seeds:
Seeds 4 or fewer, glabrous or pubescent to villous especially at margin.
Synonyms:

Skinneria Choisy, Mém. Soc. Phys. Genève 6: 487. 1834.

Spiranthera Bojer, Hort. Maurit. 226, p.p. 1837.

Tribe:
Merremieae

Mon, 2011-07-18 02:04 -- Esmond

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