Tanaidacea
Tanaidacea
Classification
- Phylum: Arthropoda
- Subphylum: Crustacea
- Class: Malacostraca
- Superorder: Peracarida
- Order: Tanaidacea
Pronunciation
How to pronounce Tanaidacea: //ˌtænəˈɪdeɪsiə//
These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.
Images
Summary
Tanaidacea is an order of small, shrimp-like crustaceans known as tanaids, which primarily inhabit marine environments but also include some freshwater species. They are characterized by their unique limb structure and reproductive methods, developing in the maternal marsupium without a true planktonic stage.
Physical Characteristics
Tanaids are small, shrimp-like creatures ranging from 0.5 to 120 millimetres (0.020 to 4.7 in) in adult size, with most species being from 2 to 5 millimetres (0.08 to 0.2 in). Their carapace covers the first two segments of the thorax. They have three pairs of limbs on the thorax; a pair of maxillipeds, large clawed gnathopods, and pereiopods adapted for burrowing. The first five abdominal segments typically have pleopods, and the final segment is fused with the telson, carrying a pair of uropods.
Identification Tips
Look for the carapace covering the first two thoracic segments, the absence of limbs on the remaining thoracic segments, and the presence of pleopods on abdominal segments.
Habitat
Most species are marine, but some are found in freshwater. They typically inhabit bottom sediments and may create self-built tubes.
Diet
Some species filter-feed on small particles while others actively hunt prey, either exclusively or in combination with filter feeding.
Life Cycle
Tanaids do not undergo a true planktonic stage; instead, the young develop within the marsupium of the mother and emerge as epibenthic forms known as mancas.
Reproduction
Some species are hermaphroditic, allowing them to possess both male and female reproductive organs.
Evolution
The oldest representatives of Tanaidacea date back to the Carboniferous, with modern forms emerging during the Mesozoic.
Similar Taxa
Misconceptions
Tanaids were formerly classified as part of Isopoda but are now recognized as a distinct order.
Tags
- Tanaidacea
- Crustacea
- Malacostraca
- Marine Life