Ebony Boghaunter

Williamsonia fletcheri Williamson, 1923

Linda LaPan

Insecta (Insects)
Corduliidae (Emeralds)
State Protection
Not Listed
Not listed or protected by New York State.
Federal Protection
Not Listed
State Conservation Status Rank
Critically Imperiled in New York - Especially vulnerable to disappearing from New York due to extreme rarity or other factors; typically 5 or fewer populations or locations in New York, very few individuals, very restricted range, very few remaining acres (or miles of stream), and/or very steep declines.
Global Conservation Status Rank
Apparently Secure globally - Uncommon in the world but not rare; usually widespread, but may be rare in some parts of its range; possibly some cause for long-term concern due to declines or other factors.


Did you know?

The larva of this rare and elusive glacial relict species was not described until the 1990s (Charlton and Cannings 1993; Mead 2003).

State Ranking Justification

The Ebony boghaunter is seldom encountered due to its secretive nature, scarce breeding habitat, and early flight season. However, there is strong reason to believe that its range has retracted significantly northward toward the Canadian border, possibly due to warming. Populations are inherently vulnerable because they are small and widely scattered (White et al., 2010).

Short-term Trends

The range in New York appears to be retracting northward toward a small core of sites in southern Franklin County (White et al, 2010).

Long-term Trends

A historical site in Broome County (1947) has likely been extirpated because it has been thoroughly searched without success over many years (White et al., 2010). This had been the southern-most known locale in the entire range.

Conservation and Management


Because it does not appear to be a strong disperser, the threats to this species stem mostly from its confinement to small, widely scattered populations (Mead 2003). Climate warming could also serve to restrict this glacial relict species to cold climate refugia (Corser et al., 2015).

Conservation Strategies and Management Practices

Site-specific management prescriptions would protect wide forest buffers around occupied or potential wetland mosaics, because these dragonflies mate, feed and perch on trees and on the ground in small clearings in the surrounding forest for much of the time, the females only briefly coming to water to to oviposit.

Research Needs

Habitat affinity is difficult to determine because the type of wetlands in which it has been located do not seem to be in limited supply. This led  Charlton (1985) and Charlton and Cannings (1993) to surmise that some distinct feature of the larval habitat is limiting. Thus, this rare species could use a thorough systematic statewide inventory. Because it has a short early flight season, is secretive, inconspicuous and occurs in small widely scattered colonies, it will likely remain under-reported, even by seasoned naturalists.



The traditional habitat description of this secretive species includes fens and acid bogs with soupy sphagnum pools surrounded by woodlands (Paulson 2011). However in New York, it seems to occupy larger wetland mosaics that can include many different types of wetland microhabitats, from open water with marshy or swampy areas, along with some presence of a fen or bog component; usually there is also running water, such as a small brook. Larvae develop in small, deep, sedge and moss-choked pools.

Associated Ecological Communities

  • Inland poor fen (guide)
    A wetland fed by acidic water from springs and seeps. Plant remains in these fens do not decompose rapidly and thus the plants in these fens usually grow on older, undecomposed plant parts of mostly sphagnum mosses.
  • Medium fen (guide)
    A wetland fed by water from springs and seeps. These waters are slightly acidic (pH values generally range from 4.5 to 6.5) and contain some dissolved minerals. Plant remains in these fens do not decompose rapidly and thus the plants in these fens usually grow on older, undecomposed plant parts of woody material, grasses, and mosses.

Associated Species

  • Aurora Damsel (Chromagrion conditum)
  • American Emerald (Cordulia shurtleffii)
  • Beaverpond Baskettail (Epitheca canis)
  • Chalk-fronted Skimmer (Ladona julia)
  • Hudsonian Whiteface (Leucorrhinia hudsonica)
  • Beaverpond Clubtail (Phanogomphus borealis)


New York State Distribution

It occurs only in extreme northern New York: Jefferson, Franklin and possibly Essex counties.

Global Distribution

This is primarily a Great Lakes and Northeastern species, known from widely separated colonies from Nova Scotia west to Manitoba, south to Wisconsin, New York and Massachusetts.

Best Places to See

  • Paul Smith's Visitor Center

Identification Comments

General Description

This small (3.0 cm) all black emerald often has some yellow or whitish markings on the thorax and abdomen. White rings separate abdominal segments 2-4. Male eyes become brilliant green with age. The sexes are similar.

Characters Most Useful for Identification

This is a very small, nearly all black emerald, with a metallic face and green eyes that often looks and behaves more like a Whiteface (Leucorrhinia).

Best Life Stage for Proper Identification



Males are often seen perching adjacent to the wetland on the ground in small sunlit openings, such as trails. Eggs are laid exophytically (outside plant tissues) and the larvae live within saturated strands of moss.


The larvae are generalist predators, while the adults feed on small flying insects.

Best Time to See

The flight season of this inconspicuous species is brief and early with the few New York records falling within about a month and a half, between May 11 to June 23.

  • Reproducing
  • Larvae present and active

The time of year you would expect to find Ebony Boghaunter reproducing and larvae present and active in New York.

Similar Species

  • Frosted Whiteface (Leucorrhinia frigida)
    Many Whitefaces (Leucorrhinia) are similar to Boghaunters, but have a pale whitish face as opposed to the metallic face and green eyes in Williamsonia.
  • Black Meadowhawk (Sympetrum danae)
    This species flies in the late summer, not May-June.

Ebony Boghaunter Images


Ebony Boghaunter
Williamsonia fletcheri Williamson, 1923

  • Kingdom Animalia
    • Phylum Arthropoda (Mandibulates)
      • Class Insecta (Insects)
        • Order Odonata (Dragonflies and Damselflies)
          • Family Corduliidae (Emeralds)

Additional Resources


Charlton, R. E., and R. A. Cannings. 1993. The larva of Williamsonia fletcheri Williamson (Anisoptera: Corduliidae). Odonatologica 22(3): 335-343.

Charlton, R.E., 1985. A colony of Williamsonia fletcheri (Odonata: Corduliidae) discovered in Massachusetts. Entomological News 96(5):201-204.

Corser, J. D., White, E. L., & Schlesinger, M. D. 2015. Adult activity and temperature preference drives region-wide damselfly (Zygoptera) distributions under a warming climate. Biology Letters, 11(4), 20150001.

Donnelly, T. W. 1992. The odonata of New York State. Bulletin of American Odonatology. 1(1):1-27.

Jones, C.D., A. Kingsley, P. Burke, and M. Holder. 2008. The Dragonflies and Damselflies of Algonquin Provincial Park and the surrounding area. Friends of Algonquin Park, Whitney, ON.

Mead, K. 2003. Dragonflies of the North Woods. Kollath-Stensaas Pub., Duluth, MN.

Needham, J.G. and M.J. Westfall, Jr. 1954. A Manual of the Dragonflies of North America (Anisoptera). University of California Press, Berkeley, California. 615 pp.

New York Natural Heritage Program. 2023. New York Natural Heritage Program Databases. Albany, NY.

Paulson, D. 2011. Dragonflies and damselflies of the east. Princeton University Press, Princeton,New Jersey, USA.

Soltesz, Ken. 1992. Proposed Heritage ranks for New York State odonata. Unpublished report for New York Natural Heritage Program. 37 pp.

Walker, E.M., and P.S. Corbet. 1975. The Odonata of Canada and Alaska. Vol 3. The Anisoptera--Three families. Univ. Toronto Press. 307 pp.

White, Erin L., Jeffrey D. Corser, and Matthew D. Schlesinger. 2010. The New York Dragonfly and Damselfly Survey 2005-2009: distribution and status of the odonates of New York. New York Natural Heritage Program, New York State Department of Environmental Conservation, Albany, NY.


About This Guide

This guide was authored by: Jeffrey D. Corser

Information for this guide was last updated on: June 30, 2017

Please cite this page as:
New York Natural Heritage Program. 2023. Online Conservation Guide for Williamsonia fletcheri. Available from: https://guides.nynhp.org/ebony-boghaunter/. Accessed December 5, 2023.