Acariformes

Mites are tiny creatures.

Many kinds of these mites live on Earth. Some mites eat plants. Others eat tiny bits of food. Some mites are bright red. These are called velvet mites. Some mites live in houses. They can live in dust. Mites have been around for a very long time. Old fossils show they lived long ago. They are very small and special.

Acariformes are a large group of mites.

Scientists have found over 32,000 kinds of these mites. Some experts think there may be nearly one million kinds in all! These mites are split into two main groups. One group is called Sarcoptiformes. They eat solid food like fungi or plants. Some of these mites live in houses. You might know the house dust mite.

The other main group is Trombidiformes. Many of these mites are plant pests. Spider mites are a well-known kind. Some mites in this group are predators. Others eat fungi or live as parasites. You can see bright red velvet mites in nature.

Mites have been on Earth for a very long time. Old fossils from Scotland are 410 million years old. One fossil mite was very large. It lived during the Cretaceous period. Some mites also help animals. Poison frogs get their poison from eating certain mites. This helps the frogs stay safe in the wild.

Acariformes are a huge group of tiny living things called mites.

Scientists have already described over 32,000 different species. They belong to 351 different families. Some experts think there are many more left to find. They estimate there could be between 440,000 and 929,000 species in total. These mites are split into two main groups. One group is called Sarcoptiformes. The other main group is called Trombidiformes.

These two groups work in different ways. Sarcoptiformes mites mostly eat solid food. They eat things like fungi or plants. Some of them are called microherbivores or fungivores. A few types, like the Psoroptidia, live near animals or insects. You might know the house dust mite or the scab mite.

Trombidiformes mites are also very diverse. Many of these are plant pests, like the spider mite. Some are predators that hunt other things. Others eat fungi or live as parasites on animals. You can see some very bright red velvet mites in the wild.

Mites have been on Earth for a very long time. We know this from looking at old fossils. The oldest ones come from the Rhynie Chert in Scotland. These fossils are from the early Devonian period. They are about 410 million years old. One very special fossil is called Immensmaris chewbaccei. It lived during the Cretaceous period. This mite was much larger than most others. It is the largest fossil mite ever recorded.

Some mites even help other animals stay safe. For example, some poison frogs get their strength from mites. The strawberry poison-dart frog is one such animal.

These frogs eat small mites called Oribatids. The mites contain special chemicals called alkaloids. When the frogs eat them, they become poisonous. If these frogs are raised without these mites, they do not develop that poison. This shows how mites are linked to the wider world.

Most mites reproduce by having a mother and a father. This is called sexual reproduction. However, some mites have found a different way. They can use a way called parthenogenesis. This means they can make babies without a partner. This has happened many times in their history. Some of these groups are very old. They likely started 300 to 400 million years ago. This helps them survive in many different places.

Acariformes, also known as the Actinotrichida, are a massive superorder of mites. They represent one of the two main superorders of mites, the other being Parasitiformes. These tiny creatures are incredibly diverse. Scientists have already described over 32,000 different species belonging to 351 families. However, many more likely exist. Experts estimate the total number of species could range from 440,000 to 929,000.

Modern scientists organize Acariformes into two primary clades, or groups. The first is Sarcoptiformes, and the second is Trombidiformes. There is also a group called Endeostigmata. These are primitive, minute, and soft-bodied mites. They ingest solid food like fungi, algae, and small invertebrates. This group includes organisms like nematodes, rotifers, and tardigrades. While some older views treated Endeostigmata as a separate suborder, modern views often include them within the Sarcoptiformes.

The Trombidiformes clade is also very complex. Within this group, the Sphaerolichida appear to be the most ancient lineage. There is also a group called the Prostigmata. Scientists struggle to define the exact relationships within the Prostigmata. They divide them into lineages like Anystina, Eleutherengona, and Eupodina. Current computer software often fails to resolve these complicated family trees perfectly. Because of this, researchers often treat these three lineages as distinct.

Sarcoptiformes mites play many roles in their environments. Most are microherbivores, fungivores, or detritivores that eat solid food. Some groups, called Psoroptidia, live near vertebrates or nest-building insects. This includes well-known species like house dust mites and scab mites. Other types include stored product mites and feather mites. Some Oribatid mites are even vital to other animals. For example, the strawberry poison-dart frog, Oophaga pumilio, eats these mites. The mites provide alkaloids, which are chemical compounds used for poison. Without these mites, the frogs do not develop their famous toxicity.

Trombidiformes mites are often noted for their impact on agriculture. Many species are significant plant parasites. This includes the spider mites of the family Tetranychidae and the Eriophyidae family. Other members of this group act as predators or animal parasites. Some are even free-living. The velvet mites of the family Trombidiidae are very easy to spot. They are often relatively large and bright red in color.

The history of Acariformes stretches back hundreds of millions of years. The oldest known fossils were found in the Rhynie Chert in Scotland. These fossils date to the early Devonian period, roughly 410 million years ago. We also have records of much larger ancient mites. One fossil species is named Immensmaris chewbaccei from the Cretaceous period. This was the largest fossil acariform mite ever recorded. It was also the largest erythraeoid mite ever found.

Reproduction in Acariformes provides a fascinating look at evolution. Most species evolved from sexual ancestors and use sexual reproduction. However, many species have developed parthenogenesis. This is a way to reproduce without needing a partner. This has occurred numerous times throughout their evolutionary history. Some parthenogenetic groups in the order Oribatida are very old. They likely emerged between 300 and 400 million years ago. In some cases, species using automixis, a form of self-fertilization, have even returned to sexual reproduction.