Violaceae Batsch

Gemma Bramley, Anna Trias-Blasi & Richard Wilford (2023). The Kew Temperate Plant Families Identification Handbook. Kew Publishing Royal Botanic Gardens, Kew

Recognition

Characters of similar families: Lentibulariaceae (Pinguicula with Viola): leaves sticky, anthers 2. Ericaceae (Leucopogon with Melicytus): exstipulate, sympetalous, stamens inserted at top of floral tube, fruit a drupe. Primulaceae-Myrsinoideae (Myrsine, Rapanea, with Melicytus): exstipulate, stamens antepetalous, staminodes 0, fruit a drupe. Euphorbiaceae (with 3-locular 3-valved capsules): capsule has central columella persistent in fruit, placentation axile or basal, 1 seed per carpel.

Morphology General Habit

Trees, shrubs, lianas, caulescent or acaulescent herbs

Morphology General Hair

Hairs often present, simple

Morphology Leaves Stipules

Stipules present

Morphology Leaves

Leaves usually alternate (rarely opposite), simple, entire, lobed or dissected, mostly lanceolate to ovate; margins glandular-toothed

Morphology Reproductive morphology Inflorescences

Inflorescence axillary or terminal; fasciculate, cymose, racemose, thyrsoid or paniculate, or flowers solitary; pedicels articulated (except Viola)

Morphology Reproductive morphology Flowers

Flowers commonly bisexual, slightly to strongly zygomorphic (mostly expressed in corolla); sepals 5, free, subequal, occasionally prominently unequal, in Viola each with a basal appendage (auricle); petals 5, free, equal or unequal, anterior petal often differentiated, dilated and/or spurred; stamens 5, antesepalous, free or connate into a tube closely encircling ovary (‘pollen cone’), anther connective often well-developed and terminating in a scale; in more zygomorphic flowers 2 filaments and/or anthers bear nectariferous glands extending into petal spur; ovary superior, 1-locular, carpels commonly 3, placentation parietal, ovules 1–many; style terminal, simple (often lobed or hooked)

Morphology Reproductive morphology Fruits

Fruit a 3-valved capsule, less often a dry or fleshy berry, nut, follicle or papery bladder

Morphology Reproductive morphology Seeds

Seeds globose to ovoid, less often flattened, winged or angled, commonly bearing an elaiosome.

Distribution

25 genera, 1,100 species. Worldwide, mostly pantropical. The three largest genera are primarily herbaceous Viola, mostly woody Rinorea, and herbaceous and suffruticose Hybanthus (polyphyletic, being dismantled).

Ecology

At low to high altitude in wet or dry habitats. Three predominantly temperate genera: Viola (525 species), Melicytus (10 species) and Cubelium (1 species).

Note

Trees, shrubs, lianas, herbs. Leaves alternate, simple, commonly stipulate. Flowers usually bisexual, slightly to strongly zygomorphic, 5-merous, anther connective well-developed, often with scale, ovary superior, 1-locular, placentation parietal, style 1. Fruit commonly a capsule or berry.

Description Author

Sue Zmartzy & Harvey Ballard

Timothy M. A. Utteridge and Laura V. S. Jennings (2022). Trees of New Guinea. Kew Publishing. Royal Botanic Gardens, Kew

Distribution

A family of 24 genera and c. 700 species. In South-East Asia there are four genera, all being found in New Guinea: Viola, Hybanthus, Agatea, and Rinorea which is the only arborescent genus.

Milliken, W., Klitgard, B. and Baracat, A. (2009 onwards), Neotropikey - Interactive key and information resources for flowering plants of the Neotropics. http://creativecommons.org/licenses/by/3.0

Morphology General Habit

Herbs, subshrubs, shrubs, treelets or trees, less frequently lianas

Morphology Leaves

Leaves alternate or less frequently opposite or pseudo- whorled, entire, serrate (the teeth bearing a terminal gland) or rarely pinnatifid or lobed; stipules present, persistent or deciduous

Morphology Reproductive morphology Inflorescences

Inflorescences of fascicles, simple or compound cymes, (pseudo-) racemes, or flowers solitary, axillary

Morphology Reproductive morphology Flowers

Flowers actinomorphic to strongly zygomorphic, bisexual or rarely unisexual, hypogynous; pedicels often articulated, bracteoles often present; aestivation usually apotact or less frequently quincuncial or convolute; sepals 5, free, equal or slightly unequal, rarely strongly unequal, persistent; petals 5, free, equal or strongly unequal in zygomorphic flowers, the lowest petal being usually bigger and gibbose or spurred; stamens 5 or rarely 3, free or the filaments fused, anthers usually with a dorsal membranous connective appendage, the filaments usually with nectar glands (in zygomorphic flowers the large nectaries are born on the filaments of the 2 dorsal stamens and are enclosed in the lowest petal's sac or spur); ovary 3-carpellate or rarely 2-4-carpellate, ovules 1-many with  parietal placentation, style straight, curved or sigmoid

Morphology Reproductive morphology Fruits

"Fruit usually a leathery capsule, less frequently a woody or papery, bladder-like capsule, rarely a "" berry "" or nut; seeds (sub -) globose or less frequently strongly flattened and winged, discoid or irregularly angled, sometimes arillate, glabrous or less frequently pubescent ."

Distribution

Amphirrhox Spreng. - S Central America, N South America and E coast of  South America. Anchietea A.St.-Hil. - Widespread in South America. Corynostylis Mart. Gloeospermum Triana & Planch. - Central America, N South America. Fusispermum Cuatrec. - S Central America, N South America. Hekkingia H.E.Ballard & Munzinger - French Guiana, N Brazil (Roraima). Hybanthopsis Paula-Souza - endemic to Bahia state (Brazil). Hybanthus Jacq. - Widespread. Leonia Ruiz & Pav. - N South America. Mayanaea Lundell - Guatemala. Noisettia Kunth - N South America and E coast of South America. Orthion Standl. & Steyerm. - Central America. Paypayrola Aubl. - S Central America, N South America. Rinorea Aubl. - Central America, N South America and E coast of South America. Rinoreocarpus Ducke - N South America. Schweiggeria Spreng. - E Brazil. Viola L. - Widespread (mainly Central America and W South America). All genera are endemic to the Neotropical region, except for Hybanthus, Rinorea and Viola.

Diagnostic

Ovarysuperior, 3-carpellate with parietal placentation. Stipules present (although sometimes deciduous). Glands present at the tip of teeth on serrate leaves. Anthers provided with membranous connective appendages. Filaments provided with nectarglands. Notable genera and distinguishing features: Lianescent habit and strongly flattened seeds in Anchietea, Corynostylis and Hybanthopsis. Pappery, bladder-like capsules in Anchietea and Hybanthopsis. Capsules opening by a single londitudinal slit in Hybanthopsis. Auriculate sepals and pedicels not articulated in Viola. Sepals strongly unequal in Schweiggeria. Aestivation of petals convolute in Fusispermum.

Note

Number of genera: 17 genera: Amphirrhox   Anchietea  Corynostylis Fusispermum Gloeospermum   Hekkingia Hybanthopsis Hybanthus Leonia Mayanaea Noisettia Orthion Paypayrola  Rinorea Rinoreocarpus Schweiggeria Viola

Timothy Utteridge & Gemma Bramley (2020). The Kew Tropical Plant Families Identification Handbook, Second Edition. Kew Publishing Royal Botanic Gardens, Kew

Note

Leaves often alternate, usually simple. Inflorescences various. Flowers commonly bisexual, 5-merous, stamens 5, glandular, anther connective often well-developed, ovary superior, 1-locular, style 1. Fruit various, elaiosome often present.

Recognition

Characters of similar families: Phyllanthaceae: fruit 3-locular. Euphorbiaceae: fruit 3-locular. Salicaceae (e.g. Casearia in fruit): disk present, anther scale absent, elaiosome absent. Primulaceae-Myrsinoideae (e.g. Myrsine in fruit): leaves, flowers and fruits with dark glandular punctations. Sapotaceae: white latex present, leaves entire. Polygalaceae: stipules absent, leaves entire, ‘keel’ petal fringed in Polygala, ovary usually 2-locular.

Morphology General Habit

Trees, shrubs, lianas or herbs

Morphology General Hair

Hairs often present, simple

Morphology Leaves Stipules

Stipules present

Morphology Leaves

Leaves commonly alternate, usually simple, mostly lanceolate to ovate; margins entire or glandular-toothed

Morphology Reproductive morphology Inflorescences

Inflorescence axillary or appearing terminal; commonly fasciculate, cymose, racemose, thyrsoid or paniculate, sometimes flowers solitary; pedicels mostly articulated, with pair of bractlets

Morphology Reproductive morphology Flowers

Flowers commonly bisexual, actinomorphic or zygomorphic (mostly expressed in corolla); sepals 5, free, subequal, occasionally prominently unequal; petals 5, free, equal or unequal; stamens 5 (rarely 3), alternating with petals, free or fused, often encircling ovary closely, bearing a nectariferous gland on 2 or 5 stamens or fused to filaments forming a tube or ‘collar’ around the style; anther connective often well-developed, terminating commonly in a rudimentary or conspicuous scale; ovary superior, 1-locular (carpels 3, rarely 4 or 5), placentation parietal, ovules 1–many; style terminal, simple (often lobed or hooked)

Morphology Reproductive morphology Fruits

Fruit a 3-valved capsule, rarely a fleshy berry, nut, follicle or papery bladder

Morphology Reproductive morphology Seeds

Seeds globose to ovoid, less often flattened, winged or angled, commonly bearing an elaiosome.

Distribution

Worldwide but (excluding Viola) predominately pantropical. Most smaller genera found in Neotropics; the three largest genera are: primarily herbaceous Viola, mostly arborescent Rinorea, and herbaceous and suffruticose Hybanthus (the latter polyphyletic, consisting of eight distinct genera).

Ecology

Low to high altitude in wet or dry habitats.

Description Author

Harvey E Ballard, Jr. & Sue Zmarzty

Violaceae, N. K. B. Robson. Flora Zambesiaca 1:1. 1960

Morphology General Habit

Shrubs or perennial or annual herbs (more rarely trees)

Morphology Leaves

Leaves alternate (rarely opposite or whorled), simple, entire or serrate to dentate (rarely ± dissected), usually with 2 stipules

Morphology Reproductive morphology Flowers

Flowers actinomorphic or, more often, ± zygomorphic, bisexual (rarely polygamous or dioecious)

Morphology Reproductive morphology Flowers Calyx

Sepals 5, free or shortly united, quincuncial or open in bud, usually persistent

Morphology Reproductive morphology Flowers Corolla

Petals 5, free, equal or ± unequal, the anterior one frequently ± spurred, imbricate, usually deciduous, alternating with the sepals

Morphology Reproductive morphology Flowers Androecium

Stamens 5, antisepalous, similar or ± dissimilar, the anterior pair in zygomorphic flowers with appendages which project into the spur, filaments free ± united, often forming a cylinder round the ovary; anthers usually introrse, free ± united, usually with a prolongation of the connective

Morphology Reproductive morphology Flowers Gynoecium

Ovary free, sessile, usually ± ovoid, 1-locular, with (2) 3 (4–5) parietal placentas each bearing 1–? ovules; styles completely united, usually thickened above, often ± S-shaped in zygomorphic flowers, stigma usually undivided

Morphology Reproductive morphology Fruits

Fruit a loculicidal capsule usually with contractile carinate valves, rarely a berry or nut

Morphology Reproductive morphology Seeds

Seeds sometimes with a small aril, usually with abundant endosperm

Violaceae, Hutchinson and Dalziel. Flora of West Tropical Africa 1:1. 1954

Morphology General Habit

Herbs, shrubs, or small trees

Morphology Leaves

Leaves alternate or rarely opposite, stipulate

Morphology Reproductive morphology Flowers

Flowers actinomorphic or zygomorphic, from solitary to paniculate

Morphology Reproductive morphology Flowers Calyx

Sepals 5, imbricate

Morphology Reproductive morphology Flowers Corolla

Petals 5, nearly equal or the lower larger and often clawed, imbricate

Morphology Reproductive morphology Flowers Androecium

Stamens hypogynous, 5, alternate with the petals; anthers 2-celled, opening lengthwise, with the connective produced beyond the cells

Morphology Reproductive morphology Flowers Gynoecium

Ovary superior, sessile, 1-celled, with usually 3 parietal placentas each with one or more ovules; style usually simple

Morphology Reproductive morphology Fruits

Fruit an elastic loculicidal capsule, one- or more-seeded

Morphology Reproductive morphology Seeds

Seeds with fleshy endosperm and central mostly straight embryo