Habitats of North Carolina
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Lotic Habitats
Piedmont and General Rocky Rivers
General Description This habitat is defined by aquatic to semi-aquatic species that are associated with rivers that possess extensive areas of riffles: there must be at least a moderate current and plentiful rocks present. All species in this habitat must be able to cope with the scouring action of the rivers.

The Odonates included in this habitat perch as adults on exposed rocks located well out in the water. Foraging and mating take place in the vicinity of the riffles. Nymphs of Neurocordulia are rock-clingers (also clinging to roots and woody debris) (Tennessen, 2018) and may therefore also stick close to the riffles. So may the nymphs of the two damselflies, who live within aquatic vegetation (Schwiebert, 2007). The nymphs of the Gomphurus species, on the other hand, may reside in substrates located away from the rocks. Gomphurus nymphs are burrowers who live in substrates -- sometimes buried quite deeply -- ranging from sand, silt, gravel, and mud (Tennessen, 2018). All of these species generally require the well-oxygenated waters associated with riffle habitats and are usually found only in unpolluted rivers.

Virtually all examples of this habitat occur west of the Fall-line and include species that occur in both the Piedmont and Mountains or in the Piedmont alone. Species restricted to the cooler rivers of the mountains are treated in the Montane Rocky Rivers habitat.

Abiotic Factors
Biotic Structure
Co-evolved Species Groups
Determining Species
Taxa Global RankState RankProbability of Extirpation (PE)
ODONATES
Calopteryx angustipennis - Appalachian Jewelwing G4S3S40.0020
Gomphurus fraternus - Midland Clubtail G5S10.3584
Gomphurus lineatifrons - Splendid Clubtail G4S20.0460
Gomphurus septima - Septima's Clubtail G3S30.0058
Gomphurus vastus - Cobra Clubtail G5S3S40.0020
Hetaerina americana - American Rubyspot G5S50.00
Hylogomphus abbreviatus - Spine-crowned Clubtail G4S3S40.0020
Neurocordulia virginiensis - Cinnamon Shadowdragon G4S10.3584
GRAMINOIDS
Carex torta - Twisted Sedge G5S30.0058
SPIDERS
Dolomedes scriptus - Striped fishing spider G5S3S40.0020
FORBS
Harperella nodosa - Harperella G2S10.3584
Justicia americana - American Water-willow G5S4S50.0002
Podostemum ceratophyllum - Hornleaf Riverweed G5S50.00
TURTLES
Pseudemys concinna concinna
SNAKES
Regina septemvittata
Expected Number of Extirpations with a PE value (Sum of PE) = 1.1410
N = Number of Extant Species with a PE value = 11
Average PE = ENE/N = 0.1037
Number of S5 species = 2
Proportion of Secure Species = Number of S5 Species/N = 0.1818
Habitat Risk Index = ENE x (1 – PSS) = 0.9336

Estimated Risk to the Determining Species
Estimated Security of the Habitat
Index of Habitat Imperilment
Identified Risks
Observed Trends
Distribution Map
Distribution
Major Conservation Reserves
Priority Areas for Surveys and Conservation Protection
Stewardship and Management Recommendations
References Schwiebert, E., 2007. Nymphs, Stoneflies, Caddisflies, and Other Important Insects: Including The Lesser Mayflies (Vol. 2). Rowman & Littlefield.

Tennessen, K.J., 2018. Dragonfly Nymphs of North America: An Identification Guide. Springer.
Updated on 2019-09-08 18:48:50