Chelicerata

High school (ages 12+)
Animals & Nature

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/chelicerata

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the subphylum?Chelicerata
2. What is the major extant classes?Arachnida (spiders, scorpions, mites, ticks), Xiphosura (horseshoe crabs), Pycnogonida (sea spiders)
3. What are Chelicerata and what animals are in this group?Chelicerata are a subphylum of arthropods that have eight legs and no antennae. They include spiders, scorpions, horseshoe crabs, mites, and ticks.
4. Why do spiders have eight legs and no antennae?Chelicerates evolved with a body plan that has eight walking legs and a pair of chelicerae instead of antennae. This helps them hunt and sense their surroundings.

Chelicerae: A pair of appendages anterior to the mouth, characteristic of Chelicerates, adapted for diverse functions including feeding and defense.
Prosoma: The anterior body tagma of Chelicerates, comprising the fused head and thorax, bearing sensory and locomotive appendages.
Opisthosoma: The posterior body tagma of Chelicerates, commonly known as the abdomen, containing vital organ systems.
Book Lungs: Respiratory organs found in many terrestrial Chelicerates, consisting of stacked, flattened lamellae for gas exchange.