Somatochlora incurvata
Incurvate emerald
Image of Somatochlora incurvata

Photo by Stuart Tingly 

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Key Characteristics

The Incurvate emerald is above-average in size for the Somatochlora genus (total length about 2 inches or 6.3 cm). The face is yellowish-brown with dark, metallic greenish markings and large, green eyes. The thorax (upper body) is brown with metallic blue-green reflections and a pair of yellowish-brown elongate spots on each side. The abdomen (lower body) is black with a dull greenish sheen, with pale areas on sides of segments 2 and 3, and smaller dull yellow-brown spots on the rear portions of segments 4 to 9. The legs are black, and brownish at the base.

Status and Rank

  • State Status: SC
  • State Rank: S3S4
  • Global Rank: G4

Occurrences

County NameNumber of OccurrencesYear Last Observed
Alger2
Chippewa132015
Delta72006
Keweenaw11900
Mackinac72014
Schoolcraft21993
Distribution map for Somatochlora incurvata

Updated 1/31/2017. Information is summarized from MNFI's database of rare species and community occurrences. Data may not reflect true distribution since much of the state has not been thoroughly surveyed.

Habitat

This species is typically associated with small pools of spring water in sphagnum bogs. This species also has been found in patterned peatlands and northern fens. These wetlands are associated with peat or marl and contain flowing groundwater rich in calcium and magnesium carbonates. Dominant vegetation in these communities includes sedges (Carex spp.), bulrushes (Scirpus spp.), rushes (Eleocharis spp.), and shrubby cinquefoil (Potentilla fruticosa). Northern fens also contain calciphiles such as false asphodel (Tofielda glutinosa) and grass-of-parnassus (Parnassia glauca) and bog plants such as leatherleaf (Chamaedaphne calyculata), Labrador tea (Ledum roenlandicum), and small cranberry (Vaccinium oxycoccos). These wetland communities are often bordered by forest such as rich conifer swamps and white cedar (Thuja occidentalis).

Specific Habitat Needs

Depositional spring needed in Headwater Stream (1st-2nd order), Pool

Natural Community Types

Methodology

For each species, lists of natural communities were derived from review of the nearly 6,500 element occurrences in the MNFI database, in addition to herbarium label data for some taxa. In most cases, at least one specimen record exists for each listed natural community. For certain taxa, especially poorly collected or extirpated species of prairie and savanna habitats, natural community lists were derived from inferences from collection sites and habitat preferences in immediately adjacent states (particularly Indiana and Illinois). Natural communities are not listed for those species documented only from altered or ruderal habitats in Michigan, especially for taxa that occur in a variety of habitats outside of the state.

Natural communities are not listed in order of frequency of occurrence, but are rather derived from the full set of natural communities, organized by Ecological Group. In many cases, the general habitat descriptions should provide greater clarity and direction to the surveyor. In future versions of the Rare Species Explorer, we hope to incorporate natural community fidelity ranks for each taxon.

Feel free to send questions and comments to Brad Slaughter at slaugh14@msu.edu.

Management

The most likely threat to this species is habitat loss and alteration. For example, commercial and residential development have resulted in the destruction and/or alteration of numerous wetlands in the state. Given that this species has been recorded from so few sites in Michigan and across its range, all known populations should be protected at this time. Maintaining the ecological integrity of the habitat is most important for the continued survival of this species at a site. It is important to maintain the hydrology and water quality of an occupied site. Clearcutting adjacent to occupied sites may adversely impact the incurvate emerald and a number of invertebrate species by altering the site's microclimate (e.g., loss of proper humidity gradient) and reducing the amount of feeding habitat and shelter during the maturation period prior to breeding. Maintaining a no cut or selective cut buffer around the wetlands would help minimize the potential for adversely impacting this and associated species.

Survey Methods

Males are usually seen during sunny weather conditions from mid-morning to mid-afternoon. In contrast, females appear to be most active on warm, but overcast, days when very few males are evident. Feeds high in clearings until after sundown, sometimes in swarms of other species. Males are not territorial and fly widely over the bog about a yard up, occasionally hovering low over small pools, or perching obliquely on a bare twig. Adults are best sampled with the use of a mesh aerial net. The bilge pump is used to clear crayfish burrows where the larvae tend to hide.

Page Citation

Michigan Natural Features Inventory. 2007. Rare Species Explorer (Web Application). Available online at http://mnfi.anr.msu.edu/explorer [Accessed Mar 30, 2017]

More Information

See MNFI Species Abstract

References

Survey References

Technical References