Benthos Flashcards
1
Q
Dreissena Polymorpha
A
- Common name: zebra muscles
- Benthos
- Native to Eurasia, but invasive in the Great Lakes region
- Effective filter feeders - remove nutrients as well as small algae and zooplankton from water column and can cause oligotrophication and profound alterations to nutrient cycling
- Colonize rapidly because they can attach to a wide array of substrates, including water supply pipes which can have large economic costs
2
Q
Trichoptera (larvae)
A
- Common name: caddisfly
- Benthos
- Caddisfly adults are terrestrial and larvae are aquatic. The larvae make protective cases made of silk which may be reinforced with other materials including leaves, sand, twigs, etc.
- Sensitive to pollution so their presence is associated with good water quality (“EPT” taxa)
3
Q
Chaoborid (larvae)
A
- Common name: glassworm or phantom midge (Diptera)
- Benthos
- Terrestrial adults and aquatic larvae
- Transparent body allows avoidance of visual predators
- Predatory adaptations:
a) Raptorial antennae to grasp prey and bring to mouth
b) Diel vertical migration - follow zooplankton prey in water column
4
Q
Anisoptera (nymph)
A
- Common name: dragonfly
- Benthos
- Terrestrial adults and aquatic nymphs are both predatory; prey can include larvae, tadpoles, and even small fish
5
Q
Benthic Organisms
A
- Living on, near or in the sediments
- Zoobenthos can be divided into two groups:
a) Insects - process detritus in lakes and streams,
b) All the other invertebrates - divided into 3 Phyla: Crustacea, Mollusca, and Annelida
6
Q
Crustacea
A
- Zoobenthos invertebrate phyla
- Anthropods
- Distinctive because of their 2 pairs of antennae and
anterior body segments bearing paired, jointed biramous appendages
7
Q
Mollusca
A
- Zoobenthos invertebrate phyla
- Characterized by a body enclosed in a hard shell and divided into two
classes:
a) Pelecypods - two halves of shell attached dorsally, e.g. clams
b) Gastropods - spiral or discoidal coiled shell, e.g. snails
