Matching Freshwater Invertebrates

ID:Microscopic, and usually unicellular

FFG - collector-gatherers, predator-engulfers, parasites, scavengers

FHG - clingers, crawler/climbers, planktonics

Importance: Abundant component of heterotrophic microbial community, collector-gatherer affect nutrient cycling and energy flow, parasitic taxa (fatal)

Kingdom Protista (protists)

Identification/distinguishing characteristics

• Multicellular, with cells specialized for different functions (as in all Animalia)

• Attached to substrate as sessile, asymmetrical colonies

• Spongelike or crusty texture; skeleton composed of glass spicules

FFG - collector-filterers

FHG - clingers

Kingdom Animalia, Phylum Porifera (sponges)

ID:

• A polyp with a ring of tentacles

• Nematocysts used to capture prey

FFG - predator-engulfers

FHG - clingers

Phylum Cnidaria, Family Hydridae (hydras)

ID:

• An unsegmented, dorsoventrally-flattened

worm

• Eyespots usually present

FFG - predator-engulfers, scavengers

FHG - crawlers

Phylum Platyhelminthes, Class Turbellaria, Order Tricladida (macroturbellarians)

ID:

• An unsegmented worm with a cylindrical body (round in cross- section)

• Body is usually light-colored (white or transparent) and often tapers to a sharp point at one or both ends

• Body is usually small (< 1 cm); parasitic Mermithidae can be larger

FFG - collector-gatherers (most taxa), parasites

FHG - burrowers, climber/crawlers

Importance: collector-gatherers affecting nutrient cycling and energy flow, can be biocontrol agents of mosquitoes

Phylum Nematoda (nematodes)

ID:

• An unsegmented worm with a cylindrical body

• Body is long (at least several cm), dark-colored, with a blunt tip at both ends

FFG - endoparasites (as larvae; adults are free-living and non-feeding)

Order Gordioidea (horsehair worms)

ID:

• Soft body enclosed in one shell

• Distinct head

FFG - scrapers (primarily), collector-gatherers

FHG - crawler-climbers (primarily), clingers, sprawlers, burrowers

Importance:

• Influence benthic algal abundance and taxonomic diversity

• Important food resource for vertebrates

• Hosts of trematodes that cause vertebrate disease

Phylum Mollusca, Class Gastropoda (gastropods)

Viviparid vs planorbid vs physid?

Viviparidae: operculum (a hard disk that covers the shell aperture) is present

Planorbidae: shell has high spire and aperture opens to the leftshell resembles a rams hornoperculum is absent;

Physidae: operculum is absent;

ID:

• Soft body enclosed in two hinged shells

• No head

FFG - collector-filterers

FHG - burrowers (Pisidiidae,Unionidae), clingers (Dreisseniidae)

Importance: Many species of Unionidae are endangered or extinct.

Phylum Mollusca, Class Bivalvia (bivalves)

ID:

• A segmented worm with suckers at both ends of the body

• Body is moderately- to highly dorsoventrally flattened

FFG - predator-piercers, parasites

FHG - clingers, swimmers

Phylum Annelida, Class Hirudinea (leeches)

ID:

• A segmented worm with a body that is

generally cylindrical in cross-section

• Chaetae occur on body segments

FFG - collector-gatherers (primarily), parasites

FHG - burrowers, crawlers

Importance

• Very abundant in eutrophic ecosystems

• Collector-gatherers influence nutrient cycling and energy flow

Phylum Annelida, Subclass Oligochaeta (oligochaetes)

ID:

• Jointed appendages (absent in some insect larvae)

• Sclerotized (hardened) head and/or mouthparts

Phylum Arthropoda (arthropods)

ID:

• Body composed of fused cephalothorax and abdomen

• Mouthparts include chelicerae and pedipalps

• 4 pairs of legs (larvae have 3 pairs of legs)

• No antennae

FFG - predator-piercers (most adults), parasites (all larvae, some adults), scavengers

FHG - swimmers, climber/crawlers

Class Arachnida, Order Trombidiformes (mites)

Identification/distinguishing characteristics

• 2 pairs of antennae

• Adults have at least 4 pairs of legs

• Breathe via gills

Phylum Arthropoda, Subphylum Crustacea (crustaceans)

Identification/distinguishing characteristics

• Body is covered by a soft coat-like carapace; head and antennae are visible

• Small body

FFG - collector-filterers (primarily), collector-gatherers, predator-engulfers

FHG - planktonics (primarily)

Class Branchiopoda, Order Diplostraca (cladocerans)

Identification/distinguishing characteristics

• Laterally-flattened body

• 7 pairs of legs

Ecology

FFG - shredders, collector-gatherers

FHG - swimmers, burrowers

Importance

• Important food resource for vertebrates

• Abundance limited by availability of structurally-complex coarse substrate

Class Malacostraca, Order Amphipoda (amphipods)

Identification/distinguishing

characteristics

• 5 pairs of legs, the first one having large claws

Ecology

FFG - shredders, scavengers, predator- engulfers

FHG - burrowers, crawlers

Importance

• Have strong influence on biodiversity

Class Malacostraca, Order Decapoda, Family Cambaridae (crayfishes)

Adult

• Small body (up to 2 mm long) that is cylindrical in cross section

• Long antennae

• 2 caudal rami

Larva and juvenile

• Nauplius has round body with 3 pairs of appendages

• Body elongates as development proceeds to copepodid (juvenile) and adult stages

FFG - collector-filterers, collector-gatherers

FHG - planktonics, swimmers

Class Hexanauplia, Subclass Copepoda (copepods)