Crustacea Flashcards
___ subphylum of arthropods
Second largest; ~67,000 species described
Crustacea are ___ arthropods, few are ___
Dominant aquatic, terrestrial
Closest related subphylum to ___, together form the clade ___
Insects and other hexapods, pancrustacea
Crustacea are the only arthropod group with ___
2 pairs of antennae
Most crustaceans have ___ and ___, and
Cephalothorax and abdomen, mandibles as mouthparts, carapace
Carapace is a ___
Plate that covers the cephalothorax
In some groups the carapace ___
Covers the entire body
Crustacean ___ is reinforced with ___
Exoskeleton, calcium carbonate
Crustaceans have ___ appendages
Biramous; 2 branches
Crustaceans have ___ circulatory system
Open
In Crustacean circulatory systems, ___ pumps ___ throughout the body
Dorsal heart, hemolymph (blood + interstitial fluid)
Nervous system is similar to ___ but with more fusion of ganglia
Annelids
Sensory organs are ___
Well-developed
Statocyst
balance organ found in the antennae
Compound eyes made up of ___
Ommatidia
___ is the most diverse crustacean classs
Malacostraca; 20,000 species
Malacostraca has ___ orders
4: Isopoda, Amphipoda, Euphausiacea, Decapoda
Isopoda are the only crustaceans with ___
Fully terrestrial species
Isopods are ___
Dorsoventrally flattened
Isopods have no ___
Carapace
Many Isopod species can ___
roll into a ball for protection
Amphipods lack ___
A carapace
Amphipods are ___
Laterally compressed
Amphipods are typically ___
Marine, with some beach dwelling, freshwater, and parasitic species
Euphausiacea
Krill
Euphausiacea has ___ species but are important as ___
90, planktonic organisms
Most Euphasuiacea are ___
Bioluminescent
Euphausiacea are major part of the diets of ___ and of ___
fish, baleen whales
Decapoda
Crabs, lobsters, crayfish and “true shrimp”
Decapoda has ___ species
18,000
Decapods have ___ pairs of walking legs
5
Decapoda size range from ___ to ___
few mm, 4 meters
Decapoda are ___
Economically important
Numerous species of Decapoda are ___
Food sources
Crabs have a variety of ___
forms
Crabs are distinguished by a ___ and ___
Broad cephalothorax, reduced abdomen
The crab body plan ___
Evolved multiple times outside of the “true crabs”
Brachyura
True crabs
Process of non-crab crustaceans independently evolving crab-like forms is known as ___
carcinization
Hexapoda are the ___ group of arthropods
Most numerous
Hexapoda have ___ walking legs
6
All Hexapoda legs are ___
Uniramous
Hexapoda have ___ tagmata
3: Head, Thorax, Abdomen
Hexapoda have ___ classes
2: Entognatha, Insecta
Insecta is the ___ group of animals
Largest
Around ___ currently described species of Insecta
1.1 million
Insecta are found in ___
Almost every habitat that supports life
Few insecta are ___, some are ___
Truly marine, intertidal
Study of insects is called ___
entomology
Insects are the only ___ capable of ___
invertebrates, flight
Insects usually have ___ of wings attached to the ___
2 pairs, thorax
True flies have modified hindwings called ___ that aid in balance during flight
halteres
Some insect groups have 1 or none ___
Pairs of wings
Insecta head typically contains ___, ___, ___
1 pair of compund eyes, 1 pair of antennae, 3 ocelli
Ocelli are ___
Simple light-detecting organs
Insects ___ are modified for special purposes
legs
Grasshoppers have ___ adapt for jumping
Hind legs
Mantises have ___ adapted for grasping prey
Forelegs
Insects have ___ diets
Varied
Most insects feed on ___, some feed on ___ or ___
plants, dead animals, hunt other animals
Many insects are ___
Parasitic
Insect ___ are specialized depending on the diet
Mouthparts
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