Mirbelioids facts for kids

Quick facts for kids Mirbelioids
Mirbelia floribunda
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Rosids
Order:	Fabales
Family:	Fabaceae
Subfamily:	Faboideae
(unranked):	NPAAA clade
(unranked):	Mirbelioids Wojciechowski et al. 2004
Type genus
Mirbelia Sm.
Genera and Subclades
See text.
Synonyms
Bossiaeeae (Benth.) Hutch 1964 Genisteae subtribe Bossiaeinae Benth. 1865 Mirbelieae (Benth.) Polhill & Crisp 1982 Podalyrieae subtribe Mirbeliinae Benth. 1837

The Mirbelioids are a special group of plants within the large Fabaceae family, also known as the pea family. This group includes many shrubs and small trees. Scientists have found that all Mirbelioids are closely related. They form a single "clade," which means they all came from a common ancestor. We know this by studying their DNA, which is like their genetic blueprint.

These interesting plants first appeared about 48 million years ago. That was during a time called the early Eocene epoch. Most Mirbelioids are shrubs with tough, leathery leaves. This helps them survive in dry areas. Their flowers are often bright yellow and red, looking a bit like "egg and bacon." You can find Mirbelioids mainly in Australia, Tasmania, and Papua New Guinea.

The name "Mirbelioids" is informal. It's not an official scientific rank like "family" or "genus." This group is special because of how their seeds develop. They have unusual features in their embryo sacs, which are parts of the plant where seeds form. Sometimes, they have extra-large cells or even multiple embryo sacs.

Over time, some Mirbelioids have changed how they are pollinated. Many started out being pollinated by bees. But some have evolved to be pollinated by birds instead! Mirbelioids also produce special chemicals called quinolizidine alkaloids. However, unlike many other pea plants, they don't make isoflavones. Many Mirbelioids have their flowers arranged in clusters called pseudoracemes.

Types of Mirbelioids

Scientists group Mirbelioids into different genera. A genus is a group of very similar plants. Here are some of the main groups within the Mirbelioids:

Giant Antipodals Group

This group is named for a unique feature in their seed development. They have special cells called "antipodal cells" that become very large. Some genera in this group include:

• Aenictophyton
• Bossiaea
• Daviesia
• Erichsenia
• Gompholobium
• Goodia
• Muelleranthus
• Paragoodia
• Platylobium
• Ptychosema
• Sphaerolobium
• Viminaria

Multiple Embryo-Sac Group

Plants in this group are known for sometimes producing more than one embryo sac. This is another unusual feature related to how their seeds grow.

Basal Grade

These are some of the earliest diverging genera in this group:

• Isotropis
• Jacksonia
• Leptosema

Callistachys Group

This group includes:

• Callistachys
• Gastrolobium

Oxylobium Grade

Some genera in this grade are:

• Chorizema
• Mirbelia
• Oxylobium
• Podolobium

Pultenaea Group

This is a larger group with many different types of plants:

• Almaleea
• Aotus
• Dillwynia
• Euchilopsis
• Eutaxia
• Latrobea
• Phyllota
• Pultenaea
• Stonesiella
• Urodon

Scientists have suggested that many of these genera might actually be combined into the single genus Pultenaea in the future.