Crayfishes and Lobsters
Astacidea
Classification
- Phylum: Arthropoda
- Subphylum: Crustacea
- Class: Malacostraca
- Superorder: Eucarida
- Order: Decapoda
- Infraorder: Astacidea
Pronunciation
How to pronounce Astacidea: /ˌæs.təˈsaɪ.diːə/
These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.
Images
Summary
Astacidea is an infraorder of decapod crustaceans that includes crayfishes and true lobsters, exhibiting distinct characteristics such as specialized claws and a worldwide distribution across various aquatic habitats.
Physical Characteristics
Astacidea are characterized by the presence of chelae (claws) on each of the first three pairs of pereiopods (walking legs), with the first pair significantly larger than the others. The last two pairs of pereiopods are typically simple without claws, except in Thaumastocheles, where the fifth pereiopod may have a small pincer.
Identification Tips
Look for the presence of large claws on the first three pairs of legs, and observe the structure of the last two pairs of legs for identification.
Habitat
Astacidea inhabit a variety of environments, including both marine and freshwater ecosystems but are absent in mainland Africa and parts of Asia.
Distribution
Astacidea members are found worldwide, both in oceans and freshwater, except for mainland Africa and certain regions of Asia.
Diet
Astacidea are omnivorous, often feeding on a diet that includes plant matter, detritus, and small animals.
Life Cycle
Details regarding the specific life cycle stages of Astacidea are not provided in the data.
Reproduction
Astacidea typically reproduce through external fertilization, with females carrying fertilized eggs on their pleopods (swimming limbs).
Predators
Common predators of Astacidea include larger fish, birds, and some mammals that feed on crustaceans.
Ecosystem Role
Astacidea play a critical role in aquatic ecosystems as both prey and predators, contributing to the food web in their environments.
Economic Impact
Astacidea, particularly lobsters and crayfishes, have significant economic importance in fisheries and aquaculture globally.
Cultural Significance
Astacidea, particularly lobsters and crayfish, are valued culturally and gastronomically in many societies, often considered delicacies.
Collecting Methods
- Traps
- Netting
- Hand collecting
Preservation Methods
- Freezing
- Canning
- Drying
Evolution
Astacidea is a sister clade to Polychelida and is part of the Reptantia group of decapods, reflecting significant evolutionary adaptations in their morphology and ecology.
Similar Taxa
- Polychelida
- Nephropoidea
- Astacoidea
- Parastacoidea
Misconceptions
Many people may confuse true lobsters in the infraorder Astacidea with spiny lobsters, which belong to a different infraorder.
Tags
- Crustacea
- Decapoda
- Lobsters
- Crayfish
- Aquatic Ecology