Superasterids

Clade of core eudicots

Food, Plant source foods, Flowering plats (angiospermae), Mesangiosperms, Eudicots, Core eudicots

Consumption area(s): Earth

Note: For better understanding, please read the article on flowering plants (angiospermae) first. If you come across unfamiliar words, you can click on any highlighted term to open the glossary with definitions of key botanical terms.

Introduction

Superasterids represent a clade of dicotyledonous seed plants within the botanical division called Angiosperms. This group forms one of the two main branches into which the eudicot angiosperms are split. The other major clade within this division is known as the Superrosids.

Description of Superasterids

The species in this clade display a wide range of growth forms, including annual or perennial herbs, shrubs, and trees. Occasionally, some species have aquatic habits or develop as vines. The group also includes chlorophyll-lacking plants and evergreens.

Leaf arrangement on the stem can be opposite or alternate, with or without stipules. Other arrangements include spiral phyllotaxy or forming basal rosettes. Leaf blades may be sessile, petiolated, or amplexicaul. Leaf shapes vary from lanceolate to ovate, with margins that can be entire, lobed, toothed, crenate, or wavy. Pinnate leaves are also found, and in Berberidopsidales, leaves are conduplicate.

Inflorescences may be cymose (determinate) or racemose (indeterminate). In some families, flowers are arranged in overlapping axillary whorls, while others have spikes. Often, flower heads are protected by multiple bracts or arranged in umbels.

Flowers can be bisexual or unisexual, mostly tetramerous (four whorls: calyx, corolla, androecium, gynoecium) or sometimes pentamerous (five parts per perianth whorl). Stamens are typically epipetalous, with numbers equal to or less than the corolla lobes. Flower symmetry varies between actinomorphic and zygomorphic. Some families exhibit resupination, a floral twist during development.

The calyx is usually gamosepalous and mostly actinomorphic, sometimes weakly zygomorphic. Instead the corolla is generally gamopetalous and mostly zygomorphic, shaped like a tube that sometimes widens distally.

The androecium typically mirrors the calyx and corolla in both number and organization. The filaments are generally adnate to the corolla, but tend to become free toward their upper portion. Anthers are commonly tetrasporangiate, basifixed, and introrse, with bilocular structure. Pollen grains are predominantly tricolpate, though other types with various aperture arrangements can also be found.

The gynoecium features a mostly superior ovary, formed by two or more united carpels, with different types of placentation. Ovules are typically small and thin-walled. The style, often slender and arising from the ovary’s base, ends in a split stigma.

The fruit types in this group are highly diverse. Most are either dry or fleshy capsules, but drupes, achenes, and schizocarps also occur. Shapes vary from round to elliptic, sometimes bilobed or elongated. Fruit opening mechanism can be explosive, septicidal, sometimes also circumscissile, or through a more or less irregular dehiscence. Alternatively, the fruits may be woody or leathery and indehiscent.

Pollination usually involves insects (like bees, flies, and beetles) or birds. Some species self-fertilize without opening their flowers (cleistogamy), which self-pollinate without opening. Bright colors in petals or bracts enhance attraction to pollinators.

Reproduction follows standard pollination and fertilization, while seed dispersal happens through multiple strategies. Some seeds are carried by wind, others by ants drawn to nutrient-rich fat bodies on the seed surface. Birds and mammals help disperse fleshy fruits, and in some cases, seeds float on water currents to new habitats.

Classification of Superasterids

This clade is divided into 1 clade and 3 orders.

Clade:

• Asterids (carrots, celery, chamomile, chicory, dandelion, eggplants, lavender, parsley, potatoes, bell peppers, chili peppers, sage, sunflower, thyme, tomatoes.)

Orders:

• Berberidopsidales (berberis)
• Caryophyllales (chard, rhubarb, spinach)