Aquatic Organisms Flashcards
These organisms are typically free floating
Plankton
These are free-floating algae
Phytoplankton
These are free-floating animals
Zooplankton
These are not true plankton, but are suspended benthic organisms
Tychoplankton
These are phytoplankton that exist within macrophyte communities
Metaphyton
These are free-swimming organisms
Nekton
Can some organisms transition between planktonic and nektonic life stages?
Yes
These are organisms adapted to the air-water interface
Pleuston
This is the microscopic component of pleuston
Neuston
These are neuston that are on top of the water surface
Epineuston
These are neuston that live below the water’s surface
Hyponeuston
These organisms are adapted to the bottom of a body of water
Benthic organisms
These are organisms that live on benthic substrate
Periphyton
Do freshwater algae have vascular systems?
No
Do freshwater algae often lack chloroplasts?
Yes
Do freshwater algae have true leaves, roots, or stems?
No
Do freshwater algae come in a variety of shapes and sizes?
Yes
Do some freshwater algae have flagella?
Yes
Are freshwater algae the major primary producers in aquatic systems?
Yes
These are excellent competitors for light because they have pigments that absorb green light in deeper waters
Cyanobacteria
What is another name for cyanobacteria?
Blue-green algae
What do cyanobacteria have to protect them from herbivory?
Mucilaginous coating
What do cyanobacteria have that act as buoyancy devices?
Gas vesicles
How thick can cyanobacteria blooms be?
1 m
How many cyanobacteria species can produce toxins?
40
What are the three major types of distributions of cyanobacteria?
Euphotic, photic, and specific depth
These cyanobacteria use gas vesicles to stay afloat
Euphotic cyanobacteria
These cyanobacteria migrate to different levels depending on time of day
Photic cyanobacteria
Photic cyanobacteria display this kind of movement
Diel movement
What region of the water body do cyanobacteria that remain at a specific depth stay?
Between epilimnion and metalimnion
This is an algal bloom that happens in the metalimnion
Metalimnetic bloom
What color are microcystis blooms?
Pea-soup green
When do microcystis blooms typically occur?
During hot, calm weather in mid- to late-summer
Microcystis have a large number of defined spherical cells held together with this
Mucilage
Are microcystis colonies free floating?
Yes
Are microcystis filamentous?
No
Are microcystis planktonic?
Yes
Does spirulina form large algal blooms?
No
Does spirulina produce toxins?
No
Does spirulina form loose colonies?
Yes
Where and when is spirulina typically found?
In standing bodies of water during late spring to fall
What is the appearance of spirulina?
Coiled thread of cells
This cyanobacteria is commonly marketed by health food producers
Spirulina
Does oscillatoria have branches?
No
Does oscillatoria have heterocysts?
No
Does oscillatoria have a mucilaginous sheath?
No
In what type of water does oscillatoria primarily bloom?
Less productive water
Is oscillatoria often free-floating?
Yes
When seen alive under a microscope, these cyanobacteria have an oscillating motion
Oscillatoria
These cyanobacteria form chains of round, barrel shaped cells with defined heterocysts
Anabaena
Is anabaena filamentous?
Yes
Does anabaena form large thick colonies?
No
In what type of water is anabaena found?
Phosphorus-rich water
What color is water that is rich in anabaena?
Pea-soup, but darker blue than microcystis
This cyanobacteria is one of the most easily recognized in the world
Nostoc
This cyanobacteria forms quarter-sized dark/yellow-green jelly mats/balls
Nostoc
At what time of year is nostoc found floating in lakes?
Mid-summer to fall
Is nostoc normally found in large numbers?
No
Does nostoc prefer to form colonies?
Yes
What shape are nostoc cells?
Bead-like
Do nostoc colonies have heterocysts?
Yes
Does nostoc have a mucilaginous sheath?
Yes
What shape are individual aphanizomenon cells?
Elongated and slightly tapered
This cyanobacteria forms thread-like shapes that join together to form colonies resembling chopped grass
Aphanizomenon
These cause aphanizomenon colonies to appear black
Gas vesicles
Are some aphanizomenon capable of producing neurotoxin?
Yes
This is the outer bivalved wall that protects diatoms
Frustule
What substance are diatom frustules made of?
Silica
At what time of the year are diatoms important primary producers in lakes?
Spring
What is diatom taxonomy based on?
Shape
This diatom order is spherical
Order Centrales
This diatom order is elongated
Order Pennales
What is the major limiting factor for diatoms?
Silicon
These are unicellular flagellated protists
Dinoflagellates
What two types of chlorophyll do dinoflagellates produce?
Chlorophyll A and C
What color are dinoflagellates?
Brown/red-brown
Dinoflagellates contain this molecule that stains black with iodine
Starch
Dinoflagellates cause these events in marine ecosystems
Red tides
What gives dinoflagellates their characteristic shapes?
Complex 3d covering
How many flagella do motile dinoflagellates have?
2
How are dinoflagellates’ two flagella arranged?
One flagellum wrapped around body, one trailing free
These primary producers contain chlorophyll A and B, reflecting green light
Green algae
Are green algaes eukaryotic?
Yes
Do green algaes have chloroplasts?
Yes
Can green algaes fix nitrogen?
No
Do green algaes have heterocysts?
No
These algae are usually unicellular protists with 1, 2, or 3 flagella
Euglenoids
Do euglenoids have an outer covering of cellulose/silica?
No
Do euglenoids contain chloroplasts?
Yes
Are euglenoids more complex than green algae?
Yes
How many membranes do euglenoids have around their chloroplasts?
3
How many membranes do green algae have around their chloroplasts?
2
Euglenoids contain this starch-like substance that does not stain black with iodine
Paramylum
Can euglenoids be both autotrophic and heterotrophic?
Yes
Euglenoids are more abundant in this type of water
Eutrophic
Are euglenoids common in streams/rivers?
No
These algae are red due to special pigment
Red algae
Does the color of red algae vary with depth?
Yes
Are red algae mostly freshwater or saltwater?
Saltwater
How long have red algae existed?
Over 2 billion years
Red algae love this type of water
Tropical water
These algae are brown due to special pigment and are adapted to cling to substrate
Brown algae
Are brown algae mostly freshwater or saltwater?
Saltwater
These are the largest brown algae
Kelps
How long can kelps grow?
30m
What are six advantages of sampling periphyton?
- Rapid reproduction/short life cycle; 2. Directly affected by physical/chemical factors; 3. Easy/cheap sampling; 4. Minimal impact on biota; 5. Standardized evaluation methods; 6. Pollutants in periphyton affect higher trophic levels
These are sometimes mistaken for algal blooms
Macroscopic plants
What are five common characteristics of macroscopic aquatic plants?
- Small size; 2. Round/spherical shape; 3. Floating; 4. Small roots, if any; 5. Green color
What are three examples of macroscopic aquatic plants?
Duckweeds, watermeal, water ferns
Clear, but red, brown, or tea-tinted water is indication of these
Tannins
The breakdown of these releases tannins into the water
Leaves
Do tannins separate out from standing water?
No
This substance is often mistaken for oil
Natural iron
Where does natural iron normally come from?
Groundwater
Natural iron can cause water to turn this color if bacteria are present
Orange
What should one do to determine if a shiny spot on the water surface is iron or oil?
Poke it with a stick
If shiny residue on the water surface is poked with a stick and breaks apart, what is its cause?
Iron precipitates
If shiny residue on the water surface is poked with a stick and does not break apart, what is its cause?
Oil
These are a common sight in streams rich with iron
Frothy orange scums
Iron bacteria oxidize iron into this substance
Iron oxide
What does iron in the water indicate?
That the water is probably fed by groundwater
These are long, filamentous iron bacteria enclosed in a stiff sheet
Sphaerotilus
What are two things that suds/foam in the water can indicate?
Normal suds or pollution
This type of suds/foam are usually colored, occur in several locations, and often disappear quickly
Normal suds
This type of suds/foam is usually white and fragrant, accumulates near the source, and does not disappear in slow-moving waters
Pollution
This makes water appear yellow-green and looks like dust floating on the surface
Pollen
These are invertebrates that are large enough to be seen with the naked eye and live in aquatic ecosystems
Macroinvertebrates
Are invertebrates a biological grouping?
No
These categorize stream consumers according to their mode of feeding rather than their taxonomy
Functional feeding groups
What are the five functional feeding groups?
- Scrapers; 2. Shredders; 3. Collectors; 4. Predators; 5. Piercers
On what do scraper macroinvertebrates feed?
Biofilm/algae
On what do shredder macroinvertebrates feed?
CPOM
On what do collector macroinvertebrates feed?
CPOM
On what do predator macroinvertebrates feed?
Other invertebrates
On what do piercer macroinvertebrates feed?
Macrophyte juices
What are two concerns with the functional feeding group classification system?
Feeding groups cross over taxonomic boundaries and can change with an organism’s life history
What are two factors that can change functional feeding groups?
Season and stream size
What are the two typical life cycles of macroinvertebrates?
- Egg -> immature -> aquatic mature form; 2. Egg -> immature -> terrestrial mature form
Many common species of this type of macroinvertebrate life cycle have small numbers of offspring and provide extended parental care
Aquatic mature macroinvertebrates
What are four factors that affect macroinvertebrate drifting?
- Time of day; 2. Season; 3. Presence/abundance of predators; 4. Life stage
This aquatic insect order contains alderflies and dobsonflies
Megaloptera
This aquatic insect order contains dragonflies and damselflies
Odonata
This aquatic insect order contains true bugs
Hemiptera
This aquatic insect order contains mayflies
Ephemeroptera
This aquatic insect order contains stoneflies
Plecoptera
This aquatic insect order contains caddisflies
Trichoptera
This aquatic insect order contains beetles
Coleoptera
This aquatic insect order contains flies
Diptera
This aquatic insect order is small in terms of diversity but large in terms of size
Megaloptera
Megaloptera larvae are usually this functional feeding group
Predators
Are Megaloptera usually found in shallow or deep waters?
Shallow waters
What are four distinguishing characteristics of megalopterans?
- 7-8 lateral abdominal filaments; 2. Simple/branched abdominal gills; 3. No wing pads; 4. Usually filament/anal claw at tip of abdomen
Odonata larvae are this functional feeding group
Predators
What type of waters do Odonata larvae prefer?
Standing/sluggish water
What are four distinguishing characteristics of Odonata larvae?
- Extendible jaw; 2. Large, complex eyes; 3. Long, thin abdomen; 4. Structure at end of abdomen
Most of this order are not aquatic, but are usually found at the surface/edge of the water
Hemiptera
These are highly modified in hemipterans
Legs
What are three distinguishing characteristics of hemipteran larvae?
- With/without external wing pads; 2. Piercing, sucking jointed beak; 3. Hard, leathery anterior wing half, membranous, veined posterior wing half
What two functional feeding groups can ephemeropterans be?
Collectors and scrapers
Ephemeropterans are specialists in these habitats
Microhabitats
What are five distinguishing characteristics of ephemeropteran nymphs?
- Usually flat-bodied; 2. External wing pads; 3. 3, sometimes 2 cerci at abdomen tip; 4. Abdominal gills; 5. 1 tarsal claw
How many times may plecopterans molt?
Up to 36 times
What two functional feeding groups can plecopterans be?
Predators or shredders
Plecopterans require high amounts of this
Oxygen
What are four distinguishing characteristics of plecopteran nymphs?
- External wing pads; 2. 2 (never 3) filamentous appendages at tip of abdomen; 3. Thoracic gills often present (gills on abdomen never past segment 3); 4. 2 tarsal claws
This is the largest order of entirely aquatic insects
Trichoptera
Trichopterans are related to these two insect groups
Butterflies and moths
What three functional feeding groups can trichopterans be?
Shredders, scrapers, collectors
What are six distinguishing characteristics of trichopteran larvae?
- No external wing pads; 2. Often make elaborate cases; 3. 2 hooks at end of abdomen (anal claws); 4. 1-segmented, inconspicuous antennae; 5. Sclerotized meso- and metathorax; 6. Branched ventral abdominal gills
This is the largest aquatic insect order in terms of diversity
Coleoptera
Coleopterans have this type of breathing system
Closed breathing system
What are four distinguishing characteristics of coleopterans?
- Sometimes hard head; 2. No wing pads; 3. 3 pairs of segmented legs; 4. Usually lack abdominal features (never have gills)
This is the largest aquatic insect order in terms of abundance
Diptera
What are three general characteristics of Diptera larvae?
- Maggot/worm-like shape; 2. Anal breathing; 3. Poorly developed
What are three distinguishing characteristics of Diptera larvae?
- No external wing pads; 2. No jointed legs (may have prolegs); 3. With/without sclerotized head
These aquatic invertebrates are omnivorous crustaceans that are an important food source for fish
Scuds
What are three distinguishing characteristics of scuds?
- 7 leg pairs; 2. 4 antennae; 3. Laterally flattened
These are scavenging, somewhat tolerant aquatic crustaceans
Sowbugs
What are three distinguishing characteristics of sowbugs?
- 7 leg pairs; 2. Flattened shape; 3. Two large antennae
These snails have an operculum and usually open to the right
Gilled snails
These snails lack an operculum and usually open to the left
Pouch/pond snail
These snails have no operculum and open in the plane of their spiralled shells
Other snails
What are four distinguishing characteristics of crayfish?
- 10 legs (2 large pinchers); 2. Many antennae; 3. Hard, chitinous body; 4. Large size
Crayfish belong to what order?
Decapoda
What are three characteristics of bivalves?
- Two shells; 2. Benthic/sediment burrowers; 3. Important filter feeders
Leeches belong to what order?
Hirudinea
What are four characteristics of leeches?
- Flattened, elongated body; 2. Not all suck blood; 3. Good swimmers; 4. Very pollution tolerant
This order contains freshwater worms
Oligochaeta
