Brook Snaketail

Ophiogomphus aspersus Morse, 1895

Ophiogomphus aspersus
Blair Nikula

Insecta (Insects)
Gomphidae (Clubtails)
State Protection
Not Listed
Not listed or protected by New York State.
Federal Protection
Not Listed
State Conservation Status Rank
Vulnerable in New York - Vulnerable to disappearing from New York due to rarity or other factors (but not currently imperiled); typically 21 to 80 populations or locations in New York, few individuals, restricted range, few remaining acres (or miles of stream), and/or recent and widespread 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?

Dragonflies of the genus Ophiogomphus are referred to as Snaketails and Ophio actually means "serpent" (Mead 2003). They get their name from the repeated color patterns on their abdomens which give them a snake-like appearance (Dunkle 2000).

State Ranking Justification

There are 21 extant occurrences in New York State, with no population estimates determined. Future survey efforts may result in the identification of additional populations.

Short-term Trends

There is no estimate of population size for this species based on statewide occurrences. State occurrences have been reported since the early 1990's in fast-flowing streams and rivers with a rocky and sandy substrate (New York Natural Heritage Program 2020). Any new location information on the Brook Snaketail in New York may be reflective of heightened interest in surveying for this species rather than a population increase or a range expansion (Holst 2005).

Long-term Trends

There are three known historical occurrence of Brook Snaketail in New York State. Twenty-one extant occurrences have been noted in St. Lawrence, Franklin, Essex, Warren, Washington, Montgomery, Rensselaer, Columbia, Dutchess, Orange, Sullivan, and Ulster counties. Population size has not been determined for these extant occurrences but is estimated to be relatively stable (New York Natural Heritage Program 2020).

Conservation and Management


Any activity which might lead to water contamination or the alteration of natural hydrology could impact Brook Snaketail populations (Holst 2005). Such threats might include roadway and agricultural run-off, industrial pollution, the building of dams, logging activity, development near their habitats, and littering (Natural Heritage Endangered Species Program 2003, Holst 2005).

Conservation Strategies and Management Practices

Any efforts to reduce agricultural run-off, salt run-off from roadways, flow manipulation, development of upland stream borders, and contamination of fast-flowing streams should be considered when managing for this species (Natural Heritage Endangered Species Program 2003, Holst 2005).

Research Needs

Further research is needed to define the distribution and population size of the Brook Snaketail. In addition, research is required to understand the habitat requirements and threats to this species, and to create appropriate management guidelines for its persistence in known locations (Holst 2005).



The Brook Snaketail inhabits clear, rapid-flowing streams that are shallow with a sandy and rocky substrate (Dunkle 2000, Needham et al. 2000). They are often found near riffles of open areas of the stream where the banks are brushy (Dunkle 2000). They also may be found in fast-flowing areas of larger rivers with similar substrate (New York Natural Heritage Program 2020).

Associated Ecological Communities

  • Cobble shore (guide)
    A community that occurs on the well-drained cobble shores of lakes and streams. These shores are usually associated with high-energy waters (such as high-gradient streams), and they are likely to be scoured by floods or winter ice floes.
  • Confined river (guide)
    The aquatic community of relatively large, fast flowing sections of streams with a moderate to gentle gradient.

Associated Species

  • Superb Jewelwing (Calopteryx amata)
  • Extra-striped Snaketail (Ophiogomphus anomalus) (guide)
  • Pygmy Snaketail (Ophiogomphus howei) (guide)
  • Maine Snaketail (Ophiogomphus mainensis)


New York State Distribution

The Brook Snaketail has been confirmed in locations from 13 counties from the eastern portion of the state. While no population estimate has been made, they are known to occur in clear, fast-flowing streams and rivers with rocky and sandy substrate (New York Natural Heritage Program 2020, Donnelly 2004). More inventories are needed to determine the full extent of its statewide range (Holst 2005).

Global Distribution

Although it is common and localized, the Brook Snaketail is spottily distributed across the northeastern United States and Great Lakes (Nikula et al. 2003). It has a substantial total known range from New Brunswick, Nova Scotia, and Quebec as well as Michigan, Maine, New Hampshire, Vermont, New York, Massachusetts, Rhode Island, Connecticut, New Jersey, Virginia, North Carolina, and Kentucky (Abbott 2007).

Best Places to See

  • Potter Brook (St. Lawrence County)
  • Ausable River
  • Upper Hudson River (Saratoga, Warren Counties)

Identification Comments

Identifying Characteristics

Snaketails are characterized by their bright green thorax and are part of the Clubtail family. As their name suggests, Clubtails have an enlarged tip on the end of their abdomens, giving them a club-like appearance. The Brook Snaketail has narrow, brown stripes on its green thorax and has a black abdomen with yellow dorsal (top) markings (Needham et al. 2000, Nikula et al. 2003). Brook Snaketail adults have a bright green thorax with narrow, brown stripes. They are 1.7-1.9 inches in length. They have green eyes and, as with all Gomphids, their eyes are separated dorsally. Legs can be either all black or may have a pale stripe on the tibia. They have a slender, black abdomen with a moderately widened "club" at the end and yellow triangular dorsal markings on abdominal segments 2-8. Yellow, rounded side spots are present on abdominal segments 9 and 10. The terminal appendages of the male are yellow and distinctive in shape from other snaketails when examined under magnification. Female Brook Snaketails have thicker abdomens than males, and their subgenital plates are about two-thirds as long as abdominal segment 9.


Gomphid larvae spend much of their time burrowing into the substrate of streams and rivers where they are found. Adults can be found perching on the ground, on emergent rocks in streams and rivers, or on leaf surfaces (Nikula et al. 2003). They also use upland borders of streams for feeding and resting (Natural Heritage Endangered Species Program 2003). Adult females oviposit by tapping their abdomens onto the surface of swift-flowing water while simultaneously releasing eggs (Nikula et al. 2003, Mead 2003).


Brook Snaketail larvae feed on smaller aquatic invertebrates and adults feed on insects which they capture in flight.

Best Time to See

Adults are active from late April through late August but the best time to see them is probably June or July (Dunkle 2000, Nikula et al. 2003). Larvae may be found in appropriate aquatic habitats year-round.

  • Present
  • Reproducing

The time of year you would expect to find Brook Snaketail present and reproducing in New York.

Similar Species

  • Riffle Snaketail (Ophiogomphus carolus)
    The Riffle Snaketail has a whitish-green thorax and the dorsal spot on abdominal segment 8 is rectangular in shape, whereas the Brook Snaketail's thorax is a grass green color and the dorsal spot on segment 8 is triangular in shape (Dunkle 2000).
  • Boreal Snaketail (Ophiogomphus colubrinus)
    This species has black facial stripes which do not appear on the Brook Snaketail (Dunkle 2000).
  • Maine Snaketail (Ophiogomphus mainensis)
    The dorsal abdominal markings found on the Maine Snaketail are more narrow than on the Brook Snaketail and are usually absent from abdominal segments 8 and 9 (Nikula et al. 2003). Male Maine Snaketails also have a more yellow club than Brook Snaketails (Dunkle 2000).

Brook Snaketail Images


Brook Snaketail
Ophiogomphus aspersus Morse, 1895

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

Additional Resources


Abbott, J.C. 2007. OdonataCentral: An online resource for the odonata of North America. Austin, Texas. Available at (accessed February 28, 2007).

Donnelly, T. 1993. Report on odonata of interest, 1992 and 1993.

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

Donnelly, T.W. 2004. The Odonata of New York State. Unpublished data. Binghamton, NY.

Dunkle, S.W. 2000. Dragonflies Through Binoculars. A Field Guide to Dragonflies of North America. Oxford University Press: New York, New York. 266 pp.

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

Natural Heritage Endangered Species Program. 2003. Brook snaketail dragonfly (Ophiogomphus aspersus). Massachusetts Division of Fisheries and Wildlife, Westborough, MA. Available (accessed February 9, 2007).

NatureServe. 2007. NatureServe Explorer: An online encyclopedia of life [web application]. Version 6.1. NatureServe, Arlington, Virginia. Available (Accessed: January 11, 2007).

Needham, J.G. and M.J. Westfall Jr. 1955. A manual of dragonflies of North America (Anisoptera) Including the Greater Antilles and the Provinces of the Mexican Border. University of California Press, Los Angeles.

Needham, J.G., M.J. Westfall, Jr., and M.L. May. 2000. Dragonflies of North America. Revised edition. Scientific Publishers: Gainesville, Florida. 939 pp.

New York Natural Heritage Program. 2007. Biotics Database. Albany, NY.

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

New York State Department of Environmental Conservation. 2005. Comprehensive Wildlife Conservation Strategy Planning Database. New York State Department of Environmental Conservation. Albany, NY.

Nikula, B., J.L. Loose, and M.R. Burne. 2003. A field guide to the dragonflies and damselflies of Massachusetts. Division of Fisheries and Wildlife, Natural Heritage and Endangered Species Program, Westborough, MA. 197 pp.

Soltesz, Ken. 1992. State odonata ranks: 1992 update and proposed revisions. Unpublished list submitted to the New York Natural Heritage Program, December 2, 1992.

Walker, E.M. 1958. The Odonata of Canada and Alaska. Vol 2. The Anisoptera-four families. Univ. Toronto Press 318 pp.


About This Guide

This guide was authored by: Erin L. White

Information for this guide was last updated on: July 21, 2020

Please cite this page as:
New York Natural Heritage Program. 2023. Online Conservation Guide for Ophiogomphus aspersus. Available from: Accessed December 5, 2023.