Content tagged with "Aquatic Invertebrates"

Photo of a spothanded crayfish viewed through creekwater.

Spothanded Crayfish

Orconectes punctimanus
The spothanded crayfish is moderately large and usually has a noticeable black spot on each pincer near the base of the movable finger. In Missouri, it is found mostly in Ozark waterways in the southeastern quarter of the state, from Callaway, Montgomery, and Warren counties south.

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Image of a fishing spider

Spotted Fishing Spider

Dolomedes triton
Spotted fishing spiders live around ponds, slow-moving streams, swampy areas, and other damp places. They are able to run across the surface of water much like water striders and will dive for prey, including small tadpoles or aquatic insects.

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Photo of a St. Francis River crayfish.

St. Francis River Crayfish

Orconectes quadruncus
The St. Francis River crayfish is rather small and dark brown, with blackish blotches or specks over the upper surfaces of the pincers, carapace, and abdomen. It is limited to the St. Francis River and its tributaries.

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Photo of an adult stonefly on a leaf


There are hundreds of species in North America
Stoneflies have a lot in common with mayflies, caddisflies, dragonflies and dobsonflies: They begin life as aquatic larvae, then molt and become winged adults. Many fish find stoneflies irresistible, and anglers take advantage of it!

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threehorn wartyback

Threehorn Wartyback

Obliquaria reflexa
Among all the mussels of Missouri, this is perhaps the easiest to recognize: As the shell grows, large knobs are produced, first on one shell and then on the other, in an alternating pattern.

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Amblema plicata
Sometimes called the blue-point, this mussel species is widely distributed in Missouri rivers and is occasionally found along reservoir margins.

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Photo of a pink planarian on a rock.

Turbellarians (Planarians; Free-Living Flatworms)

Various species in various genera (Dugesia, Planaria, etc.)
Turbellarians become the favorites of almost everyone who has taken the time to observe them. Unlike their parasitic cousins in the flatworm group, turbellarians are tiny carnivores or detritus-eaters that glide smoothly across submerged leaves and other objects.

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Photo of a vernal crayfish.

Vernal Crayfish

Procambarus viaeviridus
Adult vernal crayfish are rust red with a blackish wedge-shaped central stripe along the length of the abdomen. In Missouri, it is found only in our southeastern swamps, and then usually only seen in February and March.

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wabash pigtoe

Wabash Pigtoe

Fusconaia flava
A widespread mussel that releases its larvae in tiny red packages to attract fish hosts.

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Quadrula nodulata
This favored habitat of this vulnerable species is large streams or rivers in firm sand and mud. The bumps on the shell may help to anchor it in the river bottom.

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