Barbarous Primitive Minnow Mayfly

Siphlonurus barbarus McDunnough, 1924

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Insecta (Insects)
State Protection
Not Listed
Not listed or protected by New York State.
Federal Protection
Not Listed
State Conservation Status Rank
Not Ranked - State conservation status not yet assessed.
Global Conservation Status Rank
Critically Imperiled, Imperiled, or Vulnerable globally - Conservation status is uncertain, and could range from very high to moderate risk of extinction due to rarity or other factors. More information is needed to assign either G1, G2 or G3.


Did you know?

Mayflies are hemimetabolous, meaning they have no pupal stage. However, they have a life stage called "subimago" that is between larvae and adult. The subimago emerges from the water with wings but is sexually immature. After flying to a safe location near shore, the mayfly will molt one more time before reaching maturity (Morse et al. 2020).

Conservation and Management

Conservation Overview

In general, mayflies are considered indicators of streams and rivers with high water quality. Cool, free-flowing headwater streams and rivers provide habitat necessary for the existence of Siphlonurus barbarus . Riparian areas with intact tree canopies and few invasive species should be protected when possible.


Mayflies are sensitive to pollution and degradation or loss of habitat. Forest canopy loss in the riparian zone can increase the temperature of the stream to suboptimal levels for this species. Changes in the riparian zone can also create areas of increased sedimentation into the stream, reducing water quality (Maine Wildlife Action Plan 2015).

Conservation Strategies and Management Practices

Development, logging, and wood harvesting in the riparian zone of high elevation headwater streams should be discouraged. Disturbance could reduce the amount of intact tree canopy and reduce the stream water quality due to sedimentation and erosion. Harvesting in streamside buffers could cause erosion of the streambank, degrading water quality (Maine Wildlife Action Plan Revision 2015).

Construction of transportation corridors, e.g. roads or railroads, should be minimized near streams. If crossings are necessary, it is advisable to use a temporary bridge or culvert that retains the natural stream substrate and minimizes disturbance to banks and streambed (Maine Wildlife Action Plan Revision 2015).

Research Needs

Research should be conducted to increase the understanding of climate change and infrastructure threats to headwater streams and rivers.



Siphlonurus barbarous is primarily known to inhabit cold, high elevation headwater streams. It is known from riparian areas of northern hardwood conifer forest and boreal upland forest. (Maine State Wildlife Action Plan Revision 2015). The species of this genus reside in quiet edgewaters but deposit eggs in the flowing water of streams (McCafferty 1998).

Associated Ecological Communities

  • Hemlock-northern hardwood forest* (guide)
    A mixed forest that typically occurs on middle to lower slopes of ravines, on cool, mid-elevation slopes, and on moist, well-drained sites at the margins of swamps. Eastern hemlock is present and is often the most abundant tree in the forest.
  • Marsh headwater stream* (guide)
    The aquatic community of a small, marshy perennial brook with a very low gradient, slow flow rate, and cool to warm water that flows through a marsh, fen, or swamp where a stream system originates. These streams usually have clearly distinguished meanders (i.e., high sinuosity) and are in unconfined landscapes.

* probable association but not confirmed.


New York State Distribution

There is one documented historical occurrence in Ulster County, NY (Myers et. al. 2021).

Global Distribution

This species of mayfly has been observed in the northeastern United States of (New York, Pennsylvania, and Maine) and Canada (Nova Scotia, Ontario, and Quebec) (NatureServe 2022). There is one historical record of this species in New York State.

Best Places to See

  • Big Indian Valley (Ulster County)

Identification Comments

Identifying Characteristics

The Siphlonuridae family of mayflies have antennae that are less than twice the head width and short claws and ranges from 6-20 mm long (Merrit and Cummings 1978). Mayflies, including those of the genus Siphlonurus, have three abdominal ceri (Pennak 1975). This family has short claws, no cetae on maxilla, and tibia and tarsi are not strongly bowed (McCafferty 1998).

Characters Most Useful for Identification

The genus Siphlonurus has subtriangular gills on the first and second abdominal segments that have a double lamellae or membrane (Macroinverbates 2022).

Best Life Stage for Proper Identification



Mayflies are one of the shortest living adult insect orders. Once emerging from the stream as adults, females live only long enough to oviposit eggs in the stream (5 to 30 minutes). Males may live slightly longer (up to 24 hours) to complete the fertilization process (Macroinvertebrates 2022).

  • Present

The time of year you would expect to find Barbarous Primitive Minnow Mayfly present in New York.


Barbarous Primitive Minnow Mayfly
Siphlonurus barbarus McDunnough, 1924

  • Kingdom Animalia
    • Phylum Arthropoda (Mandibulates)
      • Class Insecta (Insects)
        • Order Ephemeroptera (Mayflies)
          • Family Siphlonuridae

Additional Common Names

  • Grey Drake
  • Minnow Mayfly

Additional Resources


Maine Department of Inland Fisheries and Wildlife. 2016a. Maine’s wildlife action plan revision: SGCN and conservation actions associated with habitat groupings: streams, rivers, lakes, and ponds. Maine Department of Inland Fisheries and Wildlife, Augusta, ME.

Maine Department of Inland Fisheries and Wildlife. 2016b. Maine’s wildlife action plan revision: Siphlonurus barbarus (a mayfly). Maine Department of Inland Fisheries and Wildlife, Augusta, ME.

McCafferty, Patrick W. 1998. Aquatic entomology: the fisherman's and ecologists' illustrated guide to insects and their relatives. Boston, Mass.: Science Books International.

Merritt, R.W. and Cummins, K.W. (eds.) 1978. An introduction to the aquatic insects of North America. Kendall/Hunt Publishing Co., Dubuque, Iowa.

Morse, J., Broomall, M., Wenzel, J., Kautz, A., Louw, M. (Eds ). 2020. The Atlas of Common Freshwater Macroinvertebrates of Eastern North America. Available from [Accessed 27 June 2022].

Myers, L. W., B. C. Kondratieff, D. E. Ruiter T. B. Mihuc. 2021 New York and New England Aquatic insect database, Lake Champlain Research Institute, SUNY Plattsburgh, Plattsburgh, NY.

NatureServe. 2022. NatureServe Explorer: An online encyclopedia of life [web application]. NatureServe, Arlington, Virginia. Available (Accessed: June 23, 2022).

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

Pennak, R. W. 1975. Freshwater Invertebrates of the United States, 2nd edition.John Wiley and Sons INC.


About This Guide

This guide was authored by: Lutz, Colleen M.

Information for this guide was last updated on: August 8, 2022

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