Acanthaceae through Cactaceae
Tropical Ecology & Conservation (472,563)
Terms Good To Know (Glossary)
Achene- a small, dry one-seeded fruit with a thin wall.
Actinomorphic- radially symmetrical flowers or meaning that they are capable of being divided into equal halves along any diameter.
Alternate leaves- where the leaves are arranged singly at different heights on the stem.
Annual- a plant that usually germinates flowers and dies in one year.
Berry- simple fleshy fruit, in which the entire ovary wall ripens into an edible substance that the seeds are embedded in.
Betalains- water soluble pigments.
Bisexual- each flower contains both male and female organs.
Bracts- floral leaves that protect developing flowers.
Capsule- A dry fruit that develops from two or more united carpels.
Capsular schizocarp- which is a fruit that splits at maturity into two or more closed one seeded parts.
Carpel- an organ at the center of a flower, having one or more ovules and having its parts fused together or with other carpels to enclose the ovule in an ovary, and consisting also of a stigma and usually a style.
Calyx- the sepals of one flower collectively.
Cleistogomous- to set seed without opening flowers.
Cloud forests- a tropical forest, often near peaks of mountains that usually has constant cloud cover throughout the year.
Compound leaves- made up of several lobes.
Cymose- a more or less flat-topped floral cluster with the central flowers opening first.
Dioecious- meaning there are separate male and female plants.
Drupes- meaning an outer fleshy part surrounds a shell (pit or stone) of hardened endocarp with a seed inside. The defining characteristic of a drupe is the hard, lignified stone or pit that comes from the ovary wall of the flower.
Exocarp- outermost layer of the fruits as the skin of a peach or grape.
Epiphyte- a plant that relies on another mechanically but not for nutrients.
Endocarp- the inner layer of a ripened or fructified ovary.
Follicle- a kind of fruit formed from a single carpel that splits to release its seeds.
Fronds- A leaf especially of a fern, cycad or palm.
Indehiscent- not opening at maturity.
Inflorescences- the flowering part of the plant.
Lianas- a woody, vigorous vine.
Loculicidal capsule- a capsule that splits open lengthwise directly into the chambers of the ovary.
Monoecious- meaning a single plant has separate male and female flowers.
Oblique- a system in which the coordinate axes are neither perpendicular nor parallel but slanted.
Opposite leaves- leaves arranged directly across from each other on the twig.
Palmate leaves- leaves that spread outwards from a central point and form a fan-like structure.
Perennial- is a plant that produces flowers and seeds more than one time in its lifespan.
Perfect flower- a flower that contains both male and female parts. It can pollinate itself and does not need other means to transfer it's pollen, which is produced in the same flower that produces the seed.
Pinnate leaves- a feathery, compound leaf with leaflets branching off a main midrib.
Pistil- the female part of the flower consisting of style, stigma, and ovary
P-plastids- several pigmented cytoplasmic organelles found in plant cells and other organisms, having various physiological functions, such as the synthesis and storage of food.
Raceme- an un-branched inflorescence of stalked flowers.
Raphides- which are needle-like crystals.
Rhizomatous (rhizomes) - having long reaching, underground horizontal stems, which have a loosely spreading habit.
Scarepose- meaning a leafless stalk growing directly from the ground (like daffodils).
Sepals- outer whorl of non-fertile parts that surround the fertile parts.
Simple leaves- leaves with a single blade and main midrib.
Spadix- a fleshy spike of numerous small flowers.
Spathe- an enlarged leaf-like bract that surrounds or partially encloses an inflorescence.
Stamens- the pollen-bearing filaments of flowers.
Stipuled- furnished with leafy appendages.
Styles- the three prominent, central female parts of the flower.
Succulent- juicy or full of juice or sap.
Tuberous- tube-like roots.
Unisexual- when the flower is either male or female.
Whorled leaves- three or more leaves arising from a single node.
Xerophytic- meaning well suited to dry conditions like the cactus.
Zygomorphic- only bilaterally symmetrical flowers
Family definitions (Alphabetical)
This family consists mostly of herbs or shrubs. The leaves are simple and opposite. The flowers are bisexual, zygomorphic and associated often with brightly colored bracts, which are floral leaves that protect the flower. The seed stalk of each seed is shaped like a hook to “fling” out the seeds for distribution. Many of these plants have red, tubular inflorescences and are very attractive to hummingbirds. Species that fall into this category are Pachystachys coccinea Nees also named Justicia coccinea and commonly called the “Cardinal’s Guard”. This plant is found in northern South America and in the West Indies. Another species is the Pachystachys lutea Nees also named Justicia lutia and commonly called the “Golden Shrimp Plant”. The common name is due to the shape and golden color of the bracets. This species is found from El Salvador to Peru. Other species of this family are common in the cloud and mountain forests of Costa Rica.
Justicia coccinea ..........................................Whitfieldia longifolia
Pachystachys lutea..................................Fittonia verschaffeltii..........................Thunbergia alata
These are perennial and often xerophytic herbs with aggregations of linear, sharp pointed leaves. The plants are erect, climbing or scarepose. The flowers are usually perfect, actinomorphic and showy with a capsule or berry-like fruit. An example species is the Dracaena reflexa, aka Pleomele reflexa, which is sometimes called the “Dragon’s Blood Tree” due to the nature of the sticky sap that trickles down the trunk when cut. Dracaena derives from the Greek word for female dragon. The plant is native to West Africa and the Canary Islands. There is another species called Dracaena marginata that goes by the “Dragon’s Blood Tree” name but is more often referred to as “Corn Lily”. This plant exists in various tropical and subtropical regions. Most Draecaenas are excellent at cleaning the air of impurities and harmful chemicals. Some are also used as a “living fencepost” in Costa Rica.
Dracaena surculosa..............................Sensevieria trifasciata cv. Laurentii
Anacardiaceae is a flowering plant family bearing fruits that are drupes. Some species produce an irritant called urushiol. Included in this family is the Anacardium occidentale, better know as the cashew. The fleshy part of the base of this plant is edible as well as the seed, which is usually roasted. Yet care must be taken because the juice from the raw shell around the seed can cause skin burns. Mangifera indica also belongs to this family, better known as the mango. It is a tree from India with a rounded crown and large delicious fruits. The bark can be used in tanning leather and as a yellow dye. Different parts of the plant can be used medicinally as well. Other plants belonging to this family are poison oak, poison ivy, sumac, smoke tree, and pistachio.
Made up of trees, shrubs, or sometimes herbs, this family usually has a milky sap. The leaves are simple and opposite or whorled. The flowers are bisexual and actinomorphic or weakly zygomorphic. The fruit is a follicle, capsule or berry. The seeds are typically flat and winged or have bits of hair at one end. Allamanda cathartica is a climbing ornamental shrub from Brazil with large tubular yellow flowers. The leaves contain a cathartic, which is a purging medicine that stimulates the evacuation of the bowels. Plumeria rubra acutifolia, known as “West Indian Jasmine”, is a native to Mexico and Tropical America. The tree can reach 40 ft. in height. The flowers are used as Leis in Hawaii and other tropical islands. Plumerias, also known as Frangipani, in general live in Mexico, Pacific Islands, the Caribbean, and South America. They have widely spaced thick succulent branches that are round or pointed and long leather, fleshy leaves in clusters. Their leaves do fall in winter for they are a deciduous plant and sensitive to the cold.
These plants are rhizomatous or tuberous herbs typically with calcium oxalate crystals or raphides and a milky sap. Leaves are usually large, spade-like and have a sheathing base. The flower is a fleshy spike or spadix partially enveloped by a bract or spathe, which is brightly colored. The tiny flowers are actinomorphic. The fruit is a berry. Species include Monstera deliciosa a spreading or climbing ornamental plant. The fruit is considered tasty by some, similar in flavor to the banana and pineapple. The Dieffenbachia picta, also known as “Dumb Cane”, can cause loss of voice after ingesting the plant because calcium crystals are released from storage packets damaged by the process of chewing and released into the plant sap causing irritation of mucus membranes for the eater. If crystals come in contact with the outer skin severe itching is the result. Children could die if they swallowed the crystals because the chemical is too strong for such small bodies. The Philodendrons are part of this family too and are popular for their ornamental foliage. They are mostly climbing plants and are found wild in tropical America and the West Indies. These plants have aerial roots and most have rich green leaves. A few species leaves have a copper color underneath, or veins that are red. Many species leaves are large, heart-shaped, oblong, arrow-shaped, or deeply lobed. The flowers have spathes that come in different colors of purple, pink, red, or greenish white.
Amorphophallus bulbifer....................Spathiphyllum sp.................................Anthurium sp.
The palm family includes plants such as the Date, Rattan, and Coconut. Cocos nucifera is a large palm growing to 30m tall. They have pinnate leaves 4-6m long. When leaves become old, they break away smoothly from the trunk. The Coconut is buoyant, allowing the fruit to travel by marine currents. This plant has spread through much of the tropics and its origin is still under debate. Fruits have been known to travel as far north as Norway’s shores. The Cocos thrive on sandy soils because they are highly tolerant of salinity. They prefer abundant sunlight, regular rainfall, and high humidity. This is why they are seen on coastal shores, the understory of moist forests, and in swamp forests. Flowering occurs continually, producing a high yield of seeds. All parts of the palm are useful and the trees high yield makes this plant of economic importance. The white part of the seed is edible and used fresh or dried. The cavity of “coconut water” contains sugars, fiber, proteins, antioxidants, vitamins, minerals, and provides electrolyte balance, making it a refreshing and nutritious drink in the hot tropics. Mixing grated coconut with hot water or milk makes coconut milk, bringing out its oil and aromatic compounds. Coconut cream is what rises to the top when coconut milk is refrigerated. Copra is the dried meat of the seed, which is the source of coconut oil. The leaves provide material for baskets and roofing hatch while the trunk is used for timber. The husk and shells can be used for fuel and are a good source of charcoal. Hollowing out the trunk can be used for containers or canoes. The roots can be used as a dye, mouthwash, or a medicine for dysentery. Carnauba wax is derived from the leaves of a palm native to Brazil, Copernica prunifera. Carnauba wax is used for automobiles, shoe polish, and in candies like the shiny-shelled Skittles. Probably the most extensively planted palm for crop use is Elaeis guineensis, the oil palm, whose fruits are crushed to produce commercial palm oil.
Chamaerops humilis.........................Mascarena lagencaulis
The genus Aristolochia is included in this family and is an ornamental vine native to Jamaica. The flower is purple-mottled and foul smelling, which attracts flies for pollination by posing as a suitable site for laying eggs. The flower has hairs pointed inward to delay the insects’ departure.
The Asclepiadaceae are mostly herbs or shrubs and have a white sap. Some species are lianas and some are cactus-like succulents with reduced leaves, which are simple and always opposite or whorled. The flowers are bisexual, nearly always actinomorphic, and commonly include an elaborate crown of nectariferous appendages. The anthers typically produce paired sacs of pollen called pollinia that are transferred as a unit during pollination. The fruit is follicle and seeds have a tuft of hairs at one end. The species Asclepias curassavica, or “Blood Flower”, is widespread in Costa Rican pastureland. This milkweed is native to tropical America and is very attractive to Monarch Butterflies. Also belonging to this family is the “Carrion flower”, Stapelia gigantea, whose aroma smells of rotten flesh to attract flies.
Stapelia gigantea...................................Asclepias curassavica
This family contains two genera, the Impatiens and Hydrocera. The latter is strictly from the area of tropical Asia and has one species Hydrocera triflora. The flowers of this species are used to dye fingernails in India. The Impatiens genus contains by far the larger number of species, up to 850 types, and inhabits North America, Europe, Africa, and Asia. The color of petals can range from pink to red to blue to brown. Although this genus comes from many ecological niches such as epiphytes on trees and rocks, to perennials, to annuals that can survive in freezing temperatures, to semi-aquatics that grow near streams, many are in danger of extinction. Most species are highly specific to a native ecological range. With a growing human population and expanding farms to feed the demand, the species are losing their selective sites. A feature unique to this plant is its explosive nature of the seeds. The ripe seeds pop under extreme pressure, scattering them up to twenty feet from the parent plant. The Impatiens also changes its sex. When the flower first opens it is male but then the pollen cap falls off and the female organ is exposed. This is probably to prevent self pollination and promote cross pollination but is not always effective. Some species can set seed without opening their flowers, this process is called cleistogamous.
Monoecious herbs, sometimes shrub-like, belong to this family. The leaves are alternate, oblique at the base, and stipuled. The flowers are unisexual and many species are throughout the Neotropics. Most are common in cloud forests.
Begonia cv. Withlacoohee........................Begonia incana
Species in this family are mostly tropical trees or shrubs. The leaves of the Bignoniaceae are typically opposite or whorled and usually pinnately compound, very legume-like. The large, showy flowers are bisexual and zygomorphic. Most fruit are capsular with winged seeds. The species Jacaranda mimosifilia is a commonly planted ornamental.
Jacaranda mimosifolia.........................Crescentia cujete
This is a family of major tropical trees such as the Ochroma pyrimidale, which we know as balsa wood, the Chorisia speciosa or “Floss silk tree”, and Ceiba pentandra or “Kapok”. The “Kapok” is what one thinks of when imagining a tropical tree with its “flying buttress” appendages that extend from the trunk to the ground. The Bombax whose common name is the “Red Silk Cotton Tree” is from tropical Asia and has a prickly trunk and palmate leaves. The common name refers to the hairs on the seeds. The Adansonia digitata, or “baobab”, or “Dead rat tree” is from tropical Africa with palmately lobed leaves and an enlarged trunk. Kenyans believed the devil planted the tree upside down due to its swollen bottle-shaped trunk and short, dumpy branches that stick up in the air like roots. The hairy brown fruit is 6-18 inches long and hang on stalks to give the impression of a hanging dead rat. The flowers are fragrant, 6 inches across and are pollinated by bats. A trunk 62 feet in diameter has been reported and several trees in Africa are estimated to be around 5,000 years old. One of the most prized tropical fruits in Indonesia comes from the Durio zibethinus, or “durian”, another species of this family. It is used in a variety of foodstuffs, including ice cream. Due to its heavy odor, the taste is presumably acquired and disagreeable to those on the first encounter.
There are three subfamilies of Bromeliaceae: Pitcairnoideae (terrestrial with pointy leaves), Bromelioideae (terrestrial epiphytic, tanks), and Tillandsioideae (epiphytes). Pitcairnoideae grow rooted in the soil. The leaves often have spiny edges, and may be thick and fleshy. The next two subfamilies are considered more evolved and many are epiphytic, absorbing water through their leaves instead of roots. In able to do this, the leaves are covered in permeable scales designed to absorb water but can seal themselves against the atmosphere to prevent drying out. Many have leaf bases that overlap each other around the base, forming a “tank” to hold water. These “tank” Bromeliads (Billabergia, Vriesea, and Guzmania) are important to several species of tree frogs whose eggs and tadpoles develop there, enabling frogs to spend their entire lives in the treetops. Bromeliads carry out C4 photosynthesis to make them more efficient users of water, important when living in the trees. The pineapple belongs to this family and first became known to Europeans after Columbus’ second voyage to the West Indies in 1493. Fifty years later this fruit was being cultivated in India. The fruit of the pineapple is actually a multiple fruit, formed from a cluster of flowers that mature into individual fruits. Each diamond-shaped section is from one flower. The “core” of the pineapple is the plant’s stalk, which continues to grow leaves at the top. This top portion can be planted to produce a new plant. The stems are a source for the commercial protein-digesting enzyme bromelain, which is used as a meat tenderizer. This enzyme is now being marketed as an anti-inflammatory agent under the name Ananase. Its protein-digesting qualities help increase blood flow and reduce swelling. The only Bromiliad to occur north of the New World tropics is the Spanish “moss,” which isn’t Spanish or a moss. An epiphyte, it grows prolifically in the trees of the southeastern United States. The tough stems are used in upholstery and Cajun architecture. Also known as long-moss, Florida moss, wood-crape, and crape-moss, Spanish moss can grow in places no other plants can, including on electrical cables of power lines. It is also used by swallow-tailed kites for their nests.
Aechmea fasciata.........................................Tillandsia sp..............................Tillandsia cyanea
This is a neotropical and subtropical group. Most plants in this family are spiny succulents with photosynthetic stems. Leaves are alternate and few in number and ephemeral, lasting for only a brief time. The leaves have areoles, a small cushioned like area, that bear spines. The flowers are bisexual and actinomorphic. The fruit is a berry with spines or bristles on the surface. This family is found in the dry parts of Costa Rica and other similar locations. Many species are epiphytic. A well known type of this family is the giant saguaro, Carnegiea gigantean, which is larger than most of the others in this group.
Cleistocactus jujuyensis........................Schlumbergera bridgesii.........................Rhipsalis baccifera
Rhipsalis quellibambensis...........................Echinocactus grusonii