Lupinus subg. Platycarpos facts for kids
Quick facts for kids Lupinus subg. Platycarpos |
|
|---|---|
 |
|
| Sundial lupine (Lupinus perennis) | |
Scientific classification  |
|
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Rosids |
| Order: | Fabales |
| Family: | Fabaceae |
| Genus: | Lupinus |
| Subgenus: | Lupinus subg. Platycarpos (S.Wats.) Kurl. |
| Type species | |
| Lupinus densiflorus Benth.
|
|
| Species | |
|
up to 500; see Lupinus |
|
| Synonyms | |
|
|
Lupinus subg. Platycarpos is a large group of lupine plants. These plants are mostly found in North, Central, and South America. They are known for having flat or round seed pods with two or more seeds inside. This group includes many different types of lupines, from small herbs to larger shrubs.
Contents
How Scientists Group Lupines
Scientists have been studying and grouping lupine plants for a long time.
Early Grouping by Watson
In 1873, a scientist named Sereno Watson first divided the lupine plants from North America into three main groups. He called these groups Lupinus, Platycarpos, and Lupinnelus. Watson based his grouping on how the plants grew and how many tiny potential seeds (called ovules) they had inside their flowers.
Most of the lupines he studied, especially those that lived for many years, were placed in the Lupinus group. The Platycarpos group included some types of lupines that lived for only one year. These plants had two ovules in their flowers and two seeds in their pods. An example is L. densiflorus. The Lupinnelus group had only one type of plant, L. uncialis. This plant had flowers that grew alone from the leaf joints and also had two ovules.
Expanding the Classification
Later, in 1907, other scientists named Ascherson and Graebner expanded this way of grouping. They applied it to all lupines found around the world. They were the first to divide the main Lupinus group into two larger subgenera: Eulupinus and Platycarpos. They also used the number of ovules and seeds as their main way to tell the groups apart.
Most of the known lupine types from both the eastern and western parts of the world were put into the Eulupinus subgenus. The Platycarpos subgenus included several types of annual lupines from the eastern part of the world. These were the same types that Watson had identified earlier.
Modern Understanding of Platycarpos
Today, the subgenus Platycarpos includes many different types of lupines from North and South America. These can be plants that live for many years (perennial) or just one year (annual). They all have two or more ovules (potential seeds) in their flowers.
In contrast, the Lupinus subgenus (another main group) includes about 12 types of lupines. These are mostly found in the Mediterranean region and Africa. They typically have at least four ovules in their flowers.
What Makes Platycarpos Lupines Special?
Lupinus subg. Platycarpos plants have several unique features.
Plant Structure
The flowers of these plants have two or more ovules, which become seeds. The seeds are usually small. The first pair of true leaves on a young plant grows in an alternating pattern. The stems are often smooth and may have a waxy coating. These plants usually branch out from a single main stem. Their leaves are smooth, sometimes waxy, or slightly fuzzy, and are often narrow.
Seed Pods and Life Cycle
The seed pods of Platycarpos lupines can be flat or round. They contain two or more seeds. These plants can be small shrubs, larger bushes, or herbaceous plants that die back in winter. While many are perennial (living for many years), some are annual (living for one year).
These plants are typically cross-pollinated, meaning they need pollen from another plant to make seeds. Their cells usually have 36, 48, or 96 chromosomes. The L. densiflorus plant is considered the main example for this subgenus.
Where They Grow
You can find Lupinus subg. Platycarpos plants all over North, Central, and South America. They especially like to grow in mountain ranges like the Andes and the Cordillera. Some types, like L. mutabilis and L. polyphyllus, are grown by people in gardens or for other uses. There are hundreds of different types of plants in this subgenus, and scientists are still studying them to understand them better.
Images for kids
-
Sundial lupine (Lupinus perennis)
