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The Caryophyllid group includes the orders Caryophyllales and Polygonales (sometimes combined in Caryophyllales). The Caryophyllales are a group of Eudicots that (except for Caryophyllaceae and Molluginaceae) produce pigments known as betalains. Florally, they resemble Asterids in some aspects and Rosids in others. There is some support now that Caryophyllids may, in fact, be a sister clade to the Asterids. They are, at least, undoubtedly a monophyletic group as currently circumscribed. Other lineages, such as the orders Saxifragales and Santalales, are still not placed with extremely high support using genetic evidence. I have lumped them here with the Caryophyllids not because they are related to them, but because this page had more room for me to list the pictures!
Purple denotes orders containing families covered in class; green denotes orders photographically represented but not covered in Biology 414. Click on the tree to skip directly to a given order.
Caryophyllid etc. families covered in class: Caryophyllales: Cactaceae (Cactus Family) Caryophyllaceae (Pink Family) Polygonales: Droseraceae (Sundew Family) Polygonaceae (Buckwheat Family)
Saxifragales: Saxifragaceae (Saxifrage Family)
Identification characteristics: Although most people might think they know a cactus when they see it (or feel it) there are many other succulent plants that have the aspect of cacti, and many also possess imposing spines. The photosynthetic portion of a cactus is its stem (cladophyll), and cacti often have obvious patches on their pads or stems from which spines radiate. These patches are nodes with short side-shoots known as areoles which, in addition to/in place of producing spines sometimes produce irritating hairs known as glochids. Glochids and spines of cacti are modified leaves. Cactus-like Euphorbiaceae generally have paired stipular spines at every node where a leaf was originally present. The flowers of Cactaceae have numerous separate tepals, the lower-most of which may appear sepal-like. They also have numerous stamens and have a variable number of fused carpels that make up their inferior ovary, which forms a berry as the fruit at maturity. Interesting stuff: Like many other succulents, cacti perform Crassulacean Acid Metabolism (CAM) by which they store carbon dioxide in organic acids and transport them away from the region of gas exchange. The carbon dioxide is then released from the acids and used to produce sugars through the Calvin cycle. This process helps minimize photorespiration, whereby oxygen binds to the crucial photosynthetic enzyme Rubisco, inhibiting the Calvin cycle. Although cacti are generally regarded as desert plants, they may be found in prairies, beaches, glades, and barrens. The Eastern Prickly Pear can be encountered in shale barrens and other thin soils even in PA. Cactaceae is almost entirely endemic to the new world, although some species have been introduced (and become invasive) in various other continents. Epiphyllum oxypetallum Dutchman's-Pipe Cactus (non-native)- The strongly-scented flowers of this species open only for one night, when they may be visited by bats. *Caryophyllaceae: (Pink Family) Identification characteristics: Caryophyllaceae are herbaceous and generally have opposite leaves. The stems are often slightly swollen at the leaf nodes. There are usually 5 sepals often fused into a calyx cup or tube. The 5 petals are distinct, and are often notched, sometimes very deeply so. The number of stamens varies, but is usually twice as many as the petals. There is one superior ovary formed from fusion of 2 to 5 carpels. The carpel count is often made evident by separate styles arising from the top of the single ovary. The fruit is almost always a capsule that opens by valves or teeth at the summit of the ovary. Interesting stuff: The name "Pink Family" refers not to their color (although many members do have pink flowers), but rather to the notching at the ends of their petals (like the sewing term...e.g. pinking shears). Most plants use anthocyanins as their major flower pigments, but Caryophyllales instead possess a different class of pigments known as betalains. Caryophyllaceae have somehow reverted back to the use of anthocyanins, but the chemical processes by which these transitions took place are not known. The most economically important plants in Caryophylaceae are ornamentals such as Carnations (Dianthus) and Baby's Breath (Gypsophila). Silene stellata Starry Campion- This tall but weak-stemmed Silene is usually found in rich woods and banks. The whorled leaves are unusual for the family. Silene virginica Fire Pink (plant)- This plant is usually found on dry, rocky slopes, but can put on a magnificent show with over 100 flowers in good soil. Silene virginica Fire Pink (flower)- The red flowers and tubular calyx are suited for hummingbirds. The stems and calyx are covered with sticky hairs. Phytolacca americana Pokeweed- All parts of Pokeweed are quite poisonous, although the young shoots are edible and often cooked as "Poke Salad." Phytolacca americana Pokeweed- The fruit stalks and unripe berries of pokeweed are bright magenta from betalain pigments, in sharp contrast to the black, fully ripe fruit. Claytonia caroliniana Carolina Spring Beauty- This species is nearly identical to C. virginiana, with wider leaves and slightly different bracts. Claytonia virginiana Spring Beauty (plants)- The flowers of Spring Beauty only open on bright days. The tubers were once used as a source of food. Claytonia virginiana Spring Beauty (flower)- The flowers show variation in the extent of magenta/pink veining in the petals. Claytonia virginiana Spring Beauty (flower)- Spring Beauties bloom in April and early May, produce seeds, and then die back until the following spring.
Order: Polygonales (sometimes included in Caryophyllales) Identification characteristics: Members of this family are most easily recognized by their leaves, which are highly modified for carnivory. Most species in the family have numerous long, glandular hairs on the leaf suface that secrete a visible droplet of sticky fluid. Dionaea is an exception, with its well-known "flytrap" leaves. Flowers may be borne in determinant, helicoid inflorescences or may be solitary. The flowers have 5 sepals, 5 petals, and 5 stamens that are all distinct or very nearly so. Three carpels constitute the superior ovary, which forms a capsule at maturity. Interesting stuff: If an unfortunate insect contacts the leaves of a sundew, it quickly becomes more and more stuck as it struggles to free itself. Sundew leaves then slowly curl around the insect over the course of a day or so and secret digestive enzymes that allow the plants to obtain nitrogen and other nutrients. Venus Fly Trap (Dionaea muscipula) is the most famous of all carnivorous plants, with its very active trapping mechanism. The plants have three "trigger" hairs on either half of their traps. Insects, attracted to the bright red color and sweet secretions inside the trap, must make contact with two of the hairs in order to spring the trap. An action potential is quickly transported to the joint between the trap and the rest of the leaf, and rapid water movement results in immediate closure of the trap (the plant has to have reflexes quicker than a fly!). The leaves of sundews and flytraps can be used more than once, although both must be replaced after about 3 uses. Droseraceae grow in wet, acidic areas, such as sphagnum bogs, where nutrient availability is low. Drosera rotundifolia Round-Leaved Sundew- This plant traps insects on the sticky tips of glandular leaf hairs. The leaf eventually folds over the insect. *Polygonaceae: (Buckwheat Family) Identification characteristics: The most easily recognizable feature of Polygonaceae are the ocrea, the stipules which are fused into a thin, papery sheath around the swollen nodes of the plants. The leaves are alternate. Plants are herbaceous or sometimes may be trailing or twining vines, but ocrea are almost always present. The flowers of Polygonaceae are variable; most have 6 tepals (sometimes appearing as 3 sepals and 3 petals). 2 tepals may be fused, giving the appearance of a 5-tepaled flower. Stamens are variable ranging from 5 to 9. There is one superior ovary comprised of 2 or 3 fused carpels. An achene is eventually formed as the fruit. Interesting stuff: Members of this family can be invasive in some habitats, and many are common garden and agricultral weeds (docks, knotweeds, etc,). Buckwheat (Fagopyrum) and Rhubarb (Rheum) are two useful members of the family. Polygonum virginianum Virginia Knotweed- Virginia Knotweed is sometimes known as Jumpseed, as the achenes are loosely attached to the rachis and pop off with ease. Polygonum virginianum Virginia Knotweed- The ocrea of Polygonaceae are often distinctively fringed or hairy, providing a good character for species identification.
Hamamelidaceae (including Altingiaceae): Hamamelis virginianus Witch Hazel- Witch Hazel blooms late in the fall after most trees (including itself) have lost the majority of their leaves. Hamamelis virginianus Witch Hazel- The individual flowers have 4 wirey petals. They are pollinated on rare warm days in late fall when few other plants are in bloom. Liquidambar styraciflua Sweetgum- Sweetgum is native to the SE portion of PA, but is widely planted as an ornamental throughout the state. Liquidambar styraciflua Sweetgum (male inflorescence)- The inconspicuous male flowers of Liquidambar help indicate that it is wind-pollinated. Liquidambar styraciflua Sweetgum (female inflorescence)- The female flowers give way to a spiny, globose aggregate of capsules when the fruit is mature. Sedum ternatum Stonecrop- Stonecrop is a succulent that can survive the dry habitat of rock ledges, where it can creep extensively. Ribes americanum Wild Black Currant- This plant and its gooseberry relatives produce good-tasting fruit. The black fruits of this species are prickle-less. *Saxifragaceae: (Saxifrage Family) Identification characteristics: Saxifragaceae are one of the hardest plant families to find field marks applicable to all members. Most in our range have basal rosettes of leaves, sometimes palmately veined and lobed. They typically have an elongated raceme of flowers. Most have 5 sepals (sometimes 4) which may be partially fused into a hypanthium, 5 distinct petals (sometimes none), (4) 5 or 10 stamens, and 2 carpels that are usually fused near their base but are distinct much of their length. They range from being partially inferior to superior. Interesting stuff: Morphology is highly variable within Saxifragaceae, complicating the taxonomic placement of the group. Current phylogenies weakly suport their placement with the Rosids or, alternatively, as a sister group to crown eudicots. Some are used ornamentally, such as Coral Bells (Heuchera) and Astilbe (Astilbe). Heuchera americana Alumroot- This plant is a close relative of garden Coral Bells, but the flowers are green and inconspicuous. It often grows on rocks. Mitella diphylla Bishop's Cap, Mitrewort (plant)- This species has two opposite leaves that subtend the inflorescence in addition to its basal rosette. Mitella diphylla Bishop's Cap, Mitrewort (flower)- The flowers, although small, are beautiful with their dissected petals, resembling snowflakes. Saxifraga michauxii Claw Saxifrage- Three of the petals in this species are often slightly larger than the other two. The white petals each have a small yellow spot. Saxifraga virginiana Early Saxifrage- Early Saxifrage is one of the first flowers to bloom in spring. It often grows directly on limestone rocks. Tiarella cordifolia Foamflower- The carpels of Foamflower develope aymmetrically. Plants in PA are colonial through creeping stems. Tiarella cordifolia Foamflower- The fluffy racemes of Foamflower are a common sight in rich woods throughout PA.
Comandra umbellata Bastard Toadflax- This dainty plant is not as innocent as it seems; its creeping rhizomes have roots that parasitize other plants. Comandra umbellata Bastard Toadflax- Bastard Toadflax has one of the widest ranges of any U.S. plant, growing from coast to coast in a variety of habitats.
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