Ohio Stoneflies

Flat-headed Clinger Mayfly Epeorus namatus (Burks, 1946)

First collection, most recent collections, locations, collectors:
1985. Guernsey Co.; Pike Co.; Ross Co.; Scioto Co. (Turkey Cr.); Washington Co.; Hall (1985)

1998. Geauga Co.; USNM
04/12/2017, 03/05/2018. Johnson's Cr., 41.2165, -81.7141, DH Dean
05/08/2018. Mirror Valley Cr., 41.2211, -81.7054, DH Dean.

= recent collection (since 2000); = earlier collection.

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Inconspicuous Flat-headed Mayfly Nixe inconspicua (McDunnough, 1924)

First collection, most recent collection, location, collector:

1993. Brown Co.(E. Fk. Little Miami R., E. of Vera Cruz at SR 131) (adults); Dark Co. (Greenville Cr.), VII-22-1993, Armitage (adults); Miami Co. (trib. Honey Cr., E of Tipp City), X-7-1993 (adults).
1994. Warren Co. (Todd Fork Little Miami R. at Roachester-Osceola Rd.), VI-6-1994 (adults); Preble Co (Sevenmile Cr. at US 127, E of Eaton), VII-9-1994 (adults). Ohio Biol. Survey.
1995. Clermont Co. (E. Fk Little Miami R. at P&G ESF, SR 50); Green Co. (Little Miami R. at end of Ford Rd. NW of Xenia), VIII-4-1995 (adults); Hardin Co. (Scioto R. downstream from CR 195, OEPA (larvae)
1996. Sandusky Co. (Wolf Cr. at TR 27 bridge), VII-6-1996 (adults), Ohio Biol. Survey.

09/05/1996. Franklin Co., Blacklick Cr., 39.8951, -82.8589, M Gray.
Not reported by Ohio EPA since 1996. May be in many reports for Nixe sp.

Butter Flat-headed Mayfly Stenonema luteum (Clemens, 1913) [listed as Maccaffertium luteum by Mayfly Central]

First collection, most recent collection, location, collector:

Adams Co.
1974. Fourteen Mile Cr., Lewis (1974)
Belmont Co.
05/09/2019. Anderson's Run, 39.930952, -80.942183, DH Dean.
Greene Co.
1985. N. Br. Caesar Cr., Hall (1985).
Not reported by Ohio EPA as a species.

Ithaca Flat-headed Mayfly Stenonema ithaca (Clemens & Leonard, 1924) [listed as Maccaffertium ithaca by Mayfly Central]

First collection, most recent collection, location, collector:

First
09/09/1982. Licking Co. N.Fk. Licking R., B Lenoble.

Ashtabula Co.
08/02/2011. W.Br. Ashtabula R., 41.73924, -80.61969, MJ Bolton.
Portage Co.
09/26/2012. Aurora Branch, 41.304155, -81/31063, A Dripps.

Aphrodite's Flat-headed Mayfly Leucrocuta aphrodite (McDunnough (1926)

First collection, most recent collection, location, collector:

1985. Belmont Co. (Captina Cr.); Monroe Co. (Sunfish Cr.); Hall (1985)
1998. Highland Co. (Paint Cr.); Morrow Co. (W. Br. Alum Cr.), Colorado State U.; Marion Co (Little Scioto R.) Ohio Biol. Survey; Clinton Co., Lake Co., Purdue Entomol. Res. Center.
The Ohio EPA have stopped taking the genus Leucrocuta to species.

Quill Gordon Flat-headed Mayfly Epeorus pleuralis (Banks, 1910)

First collection, most recent collections, locations, collectors:

1984. Lake Co. (Stony Brook); Robertson (1984)

05/08/2018. Mirror Valley Cr., 41.2211, -81.7054, DH Dean.

Elegant Flat-headed Mayfly Heptagenia elegantula (Eaton, 1885)

First collection, most recent collections, since 2000, locations, collectors:

First
05/15/1981. Wood Co., Yellow Cr., 41.1989,m -83.8614, B.Lenoble.
Carroll Co.
08/24/2016. Conotton Cr., 40.4456, -81.1969, S Macy.
Defiance Co.
09/19/2013. Mud Cr., 41.3503, -84.4381, MJ Bolton.
Fulton Co.
08/27/2013. Bean Cr., 41.6231, -84.2961, MJ Bolton.
Marion Co.
08/19/2009. Rush Cr., 405594, -83.3322, C McKnight.
Williams Co.
06/24/2013. Bates Cr., 41.5839, -84.3514, MJ Bolton.

Yellow Flat-headed Mayfly Heptagenia flavescens (Walsh, 1862)

First collection, most recent collections, since 2010, locations, collectors:

First
08/28/1980. Montgomery Co., Great Miami R., 39.6438, -84.2311, Ohio EPA Biologist.
Carroll Co.
06/16/2010. Stilll Fork, 40.633969, -80.98582, D Eicher.
Cuyahoga Co.
08/27/2014. Chagrin E., 41.49551, -81.40153, MJ Bolton.
Hamilton Co.
08/08/2016. Whitewater R., 39.1831, -84.7928, S Macy.
Lake Co.
09/04/2014. Chagrin R., 41.589649, -81.40254, MJ Bolton.

Dusky Flat-headed Mayfly,Heptagenia pulla, (Clemens, 1913)

First collection, most recent collection, location, collector:

1935, Lake Co., near Willowick, OH (Lake Erie ?); Traver (1935).
Not recognized by Ohio EPA.

Hebe's Flat-headed Mayfly Leucrocuta hebe, (McDunnough, 1924)

First collection, most recent collection, location, collector:

First
1935. Lake Co. near Kirkland (E. Br. Chagrin R.), near Leroy (Twp?), (Grand R.), Medina Co. (?, not given by Traver) Traver (1935)
1998. Adams Co. (Lick Fork Ohio Brush Cr., Ohio Brush Cr., Treber Run), Brown Co. (E. Fork Little Miani R.), Clermont Co. (Dry Run, Stonelick Cr.), Clinton Co. (Todd Fork), Darke Co. (Greenville Cr., Krout Cr.), Green Co.. (Massies Cr.), Huron Co. (Southwest Br. Vermilion R.), Warren Co. (Todd Fork Little Miami R., Ohio Biol. Survey; Hardin Co. (Panther Cr.), Wood Co. (Rocky Fork), OEPA; Warren Co. (Little Miami R.), Purdue Entomol Res. Ctr.; Geauga Co., U.S. Nat'l Museum.
The Ohio EPA has not reported finding this species since 1994.They have stopped taking the genus Leucrocuta to species.

Midwestern Flat-headed Mayfly Leucrocuta maculipennis, (Walsh, 1863)

First collection, most recent collection, location, collector:
First
1935. Lake Co., near Kirkland (E. Br. Chagrin R.), Leroy and Painesville (Grand R.), Medina Co. (? not given by Traver), Traver (1935).
Medina Co.
05/232017. Johnson's Cr., 41.2165, -81.7141, DH Dean.
Ohio EPA has not reported this species since 1986. They have stopped taking the genus Leucrocuta to species.

Walshs'Flat-headed Mayfly Leucrocuta walshi (McDunnough, 1926)

First collection, most recent collection, location, collector:

1935. Monroe Co. (Sunfish Cr.), Hall (1985).
1998. Morrow Co. (W. Br. Alum Cr.), Ross Co. (Ralston Cr.), Scioto Co. (Scioto R.), Colorado State U.; Brown Co. (Red Oak Cr.), Clermont Co. (trib. Lick Fork), Delaware Co. (Alum Cr., Bokes Cr., Worf Cr.), Marion Co. (Little Scioto R., McDonald Cr.), Morrow Co. (Indigo Cr.), Sandusky Co. (E. Br. Wolf Cr., Wolf Cr.), Shelby Co. (Rush Cr.), Union Co. (Mill Cr.), Ohio Biol. Survey.
Ohio EPA does not report this species since 1986. They have stopped taking the genus Leucrocuta to species

Ontario Flat-headed Mayfly Nixe perfida (McDunnough, 1926)

First collection, most recent collection, location, collector:
First
1985. Guernsey Co., Meigs Co., Noble Co. (Yoker Run), Hall (1985).
Hocking Co.
05/15/2019. E.Fk. Queer Cr., 39.4197, -82.5093, DH Dean.
Not reported by Ohio EPA since 1997. May be in many reports for Nixe sp.

Rusty Flat-headed Mayfly Nixe rusticalis (McDunnough, 1931)

First collection, most recent collection, location, collector:

1935. Lake Co., Willoughby (Chagrin R.) as Heptagenia rusticalus, Traver (1935).
1998. Miami Co. (trib. to Honey Cr.), Ohio Biol. Survey.
Not listed by Ohio EPA. May be in many reports for Nixe sp.

Wallace's Deepwater Mayfly Raptoheptagenia cruentata, (Walsh, 1863)

First collection, most recent collection, location, collector:

1977. Brown Co. (Ohio R.) as Anepeorus sp., Beckett (1977).
Not listed by Ohio EPA

Meager Flat-headed Mayfly Stenonema exigiuum, Traver (1935)[listed as Maccaffertium exigiuum by Mayfly Central]

First collection, most recent collection, location, collector:

First
1974. Clermont Co. (E. Fk. Little Miami R., Little Miami R.), Hamilton Co. (Little Miami R.), Scioto Co. (Scioto R.), Lewis (1974).
Adams Co.
08/24/2016. E.Fk. Eagle Cr., 38.7955, -83.6538, MJ Bolton.
Ashtabula Co.
09/15/2015. Conneaut Cr., 41.901902, -80.65283, S Macy.
Athens Co.
08/15/2016. Hewett Fork, 39.3175, -82.2781, M Gray.
Butler Co.
09/09/2010. Great Miami R., 39.4814, -84.4428, C McKnight.
Carroll Co.
08/24/2016. Conotton Cr., 40.4466, -81.1969, S Macy.
Clark Co.
08/22/2011. Little Miami R., 39.8325, -83.6944, A Dripps.
Clermont Co.
08/24/2012. D.Fk. Little Miami R., 39.0525, -84.05, C McKnight.
Coshocton Co.
09/27/2017. Tuscarawas R., 40.2919, -81.75, C McKnight.
Cuyahoga Co.
09/13/2017. Cuyahoga R., 41.4097, -81.6344, C McKnight.
Darke Co.
08/27/2013. Greenville Cr., 40.1003, -84.6181, C McKnight.
Defiance Co.
09/27/2013. St. Joseph R., 41.3856, -84.8017, L Hughes.
Erie Co.
08/25/2016. Huron R., 41.3017, -82.6069, C McKnight.
Fairfield Co.
08/22/2011. Scippo Cr., 39.5397, -82.8456, J Freda.
Fayette Co.
08/29/2011. Deer Cr., 39.659761, -83.26301, C McKnight.
Franklin Co.
09/08/2016. Scioto R., 39.9583, -83.0044, MJ Bolton.
Fulton Co.
08/27/2013. Bean Cr., 41.6231, -84.2961, MJ Bolton
Gallia Co.
08/01/2017. Symmes Cr., 38.7672, -82.4369, E Moore.
Greene Co.
09/22/2011. Little Miami R., 39.70738, -83.99127, C McKnight.
Guernsey Co.
09/18/2014. Wills Cr., 40.168241, -81.64863, L Hughes.
Hamilton Co.
09/18/2017. Whitewater R., 39.2489.-84.8197, S Macy.
Harrison Co.
08/24/2016. Conotton Cr., 40.4178, -81.1464, S Macy.
Henry Co.
09/06/2016. Maumee R., 41.3206, -84.2, C McKnight
Hocking Co.
06/08/2010. Clear Cr., 39.5883, -81.5776, DH Dean.
Holmes Co.
08/24/2017. Middle Fk. Sugar Cr., 40.6406, -81.6756, C McKnight.
Huron Co.
08/24/2016. W.Br. Huron R., 41.2456, -82.6914, C McKnight.
Jackson Co.
09/07/2016. Little Raccoon Cr., 39.0094, -82.445, M Gray.
Lawrence Co.
08/24/2016. Symmes Cr., 38.4847, -82.455, E Moore.
Lorain Co.
09/04/2014. W.Br. Rocky R., 41.331, -81.9182, A Dripps.
Lucas Co.
09/06/2016. Maumee R., 41.5, -83.7128, S Macy.
Madison Co.
08/26/2014. Big Darby Cr., 40.091308, -83.25552, C McKnight.
Mahoning Co.
09/17/2013. Mahoning R., 41.105, -80.6638, A Dripps.
Medina Co.
05/23/2017. Johnson's Cr., 41.2165, -81.7141, DH Dean.
05/08/2018. Mirror Valley Cr., 41.2211, -81.7054, DH Dean.
Meigs Co.
09/15/2015. Shade R., 39.063378, -81.88176, C McKnight.
Miami Co.
08/24/2015. Stillwater R., 39.985341, -84.31457, C McKnight.
Montgomery Co.
09/13/2017. Great Miami R., 39.6406, -84.2922, C McKnight.
Noble Co.
08/29/2014. S.Fk. Seneca Fork, 39.8433, -81.3175, L Hughes.
Paulding Co.
08/22/2012. Maumee R., 41.2219, -84.6697, M Gray.
Pickaway Co.
09/08/2016. Scioto R., 39.6014, -82.9553, S Macy.
Pike Co.
10/11/2011. Scioto R., 39.0978, -82.9747, C McKnight.
Portage Co.
08/28/2018. Congress Lake Outlet, 41.100026, -81.30057, C McKnight.
Ross Co.
09/09/2016. Scioto R., 39.3469, -82.9836, MJ Bolton.
Scioto Co.
09/08/2016. Scioto R. , 38.8333, -83.0183, L Hughes.
Stark Co.
09/13/2017. Sugar Cr., 40.6469, -81.5697, C McKnight.
Summit Co.
09/20/2017. Cuyahoga R., 41.1392, -81.3922, C McKnight.
Trumbull Co.
09/19/2013. Mahoning R., 41.2439, -80.865, A Dripps.
Tuscarawas Co.
09/28/2017. Tuscarawas R., 40.6092, -81.4286, C McKnight.
Vinton Co.
09/01/2016. Raccoon Cr., 39.0478, -82.3764, M Gray.
Warren Co.
09/20/2011. Little Miami R., 39.555, -84.0311, M Gray.
Washington Co.
09/23/2015. Little Muskingum R., 39.4481, -81.3364, L Hughes.
Wayne Co.
09/13/2017. Sugar Cr., 40.75, -81.6708, C McKnight.
Williams Co.
09/26/2013. St. Joseph R., 41.4892, -84.7306, L Hughes.

Flat-headed Mayfly Stenonema mexicanum integrum (McDunnough, 1924) [listed as Maccaffertium mexicanum integrum by Mayfly Central]

First collection, most recent collection, location, collector:

First
1973. Clermont Co. (Little Miami R.), Scioto Co. (Ohio R.), Lewis (1973).
Auglaize Co.
09/06/2019. Auglaize R., 40.6305, -84.2565, C McKnight.
Butler Co.
09/09/2010. Great Miami R., 39.4814, -84.4428, C McKnight.
Clermont Co.
08/16/2012. E.Fk. Little Miami R., 39.1025, -84.1956, C McKnight.
Coshocton Co.
08/27/2017. Tuscawaras R., 40.2919, -81.75, C McKnight.
Defiance Co.
09/07/2016. Maumee R., 41.2867, -84.4381, MJ Bolton.
Delaware Co.
08/31/2016. Olentangy R., 40.2985, -83.0618, MJ Bolton.
Fairfield Co.
08/22/2011. Scippo Cr., 39.5397, -82.8456, J Freda.
Franklin Co.
10/05/2015. Big Walnut Cr., 39.8678, -82.9317, S Macy.
Guernsey Co.
09/18/2014. Wills Cr., 40.168242, -81.64863, L Hughes.
Hamilton Co.
09/18/2017. Whitewater R., 39.2489, -84.8197, S Macy.
Henry Co.
09/06/2016. Maumee R., 41.3206, -83.2, S Macy.
Holmes Co.
07/18/2017. Crabapple Cr., 40.6417, -81.6925, C McKnight.
Heron Co.
08/23/2016. W.Br. Heron R., 41.1317, -82.7097. C McKnight.
Lake Co.
08/25/2010. Chagrin R., 41.59176, -81.40685, M Gray.
Lucas Co.
09/06/2016. Maumee R., 41.5, -83.7126, S Macy.
Madison Co.
08/26/2011. Deer Cr., 39.757261, -83.7127, C McKnight.
Miami Co.
08/22/2013. Stillwater R., 39.9644, -84.3242, C McKnight.
Montgomery Co.
09/13/2016. Great Miami R., 39.6406, -84.2922, C McKnight.
Paulding Co.
09/26/2017. Middle Cr., 41.019367, -84.42925, S Macy.
Pickaway Co.
09/04/2014. Big Darby Cr., 39.7864, -83.1531, C McKnight.
Pike Co.
09/04/2014. Big Darby Cr., 39.7864, -83.1531, C McKnight.
Putnam Co.
09/07/2016. Auglaize R., 41.0208, -84.2889, S Macy.
Ross Co.
09/09/2016. Scioto R., 39.3469, -82.9836, MJ Bolton.
Scioto Co.
09/08/2016. Scioto R., 38.8333, -83.0183, L Hughes.
Stark Co.
08/28/2019. Tuscarawas R., 40.8069, -81.5272, E Moore.
Summit Co.
08/14/2018. Tinkers Cr., 41.308144, n-81.43689, C McKnight.
Tuscarawas Co.
09/28/2017. Tuscarawas R., 40.6092, -81.4286, C McKnight.
Van Wert Co.
09/16/2015. St. Marys R., 40.7494, -84.7903, C McKnight.

Modest Flat-headed Mayfly Stenonema modestum (Banks, 1910)

First collection, most recent collection (none since 2007), location, collector:

First
08/29/1997. Clermont Co., Bullskin Cr., 38.8008, -84.0586, MJ Bolton.
1998. Miami Co. (Stillwater R.), Adams Co. (Brush Cr., Treber Run), Ashland Co. (Mohican R.), Brown Co. (E. Fork Little Miami R.), Clark Co. (trib. Mud Run), Clermont Co. (Backbone Cr., E. Fork Little Miami R., Stonelick Cr.), Clinton Co. (Todd Fork), Delaware Co. (Fulton Cr.), Green Co. (Little Miami R., Massies Cr., N. Br. Caesar Cr.), Miami Co. Greenville Cr., trib. Honey Cr.), Preble Co. (Little Fourmile Cr., Paint Cr., Price Cr.), Warren Co. (Little Miami R., Todd Fork Little Miami R.), Ohio Biol. Survey.
Ashtabula Co.
08/07/2007. Crooked Cr., 41.6543, -80.9238, MJ Bolton.
Carroll Co.
08/09/2005. Trib. Yellow Cr., 40.472, -890.9299, J Freda.
Geauga Co.
09/12/2007. Spring Cr., 41.6361, -81.0213, MJ Bolton.
Lake Co.
08/18/2004. Paine Cr., 41.7175, -81.1706, MJ Bolton.

[listed as Maccaffertium modestum by Mayfly Central]

Pretty Flat-headed Mayfly Stenonema pulchellum (Walsh, 1862). [

listed as Maccaffertium puchellum by Mayfly Central]

First collection, most recent collection, location, collector:

First
1942. Ottawa Co. (Lake Erie), Shelford & Boessel (1942).
1958. Champaigh Co. (Mad R.), Gaufin (1958).
Allen Co.
09/09/2019. Auglaize R., 40.7078, -84.2733, C McKnight.
Ashtabula Co.
09/17/2015. Conneaut Cr., 41.9039, -80.5294, S Macy.
Auglaize Co.
09/09/2019, Auglaize R., 40.6681, -84.2717, C McKnight.
Belmont Co.
05/09/2019. Anderson's Run, 39.930952, -80.942183, DH Dean.
Brown Co.
08/23/2016. Eagle Cr., 38.75, -83.7672, MJ Bolton.
Butler Co.
09/21/2017. Dry Fk. Whitewater R., 39.3269, -84.7486, S Macy.
Carroll Co.
08/24/2016. Conotton Cr., 40.4597, -81.2108, S Macy.
Champaign Co.
08/12/2014. Pleasant Run, 40.2123, -83.4977, C McKnight.
Clark Co.
08/22/2011. Little Miami R., 39.8325, -83.6944, A Dripps.
Clermont Co.
09/09/2014. Bullskin Cr., 38.8008, -84.0586, C McKnight.
Columbiana Co.
08/10/2010. Sandy Cr., 40.744433, -81.08156, D Eicher.
Coshocton Co.
09/27/2017. Tuscarawas R., 40.2919, -81.75, C McKnight.
Cuyahoga Co.
09/20/2017. Chagrin R., 41.517731, -81/403042, C McKnight.
Darke Co.
09/04/2013. Stillwater R., 40.1867, -84.4733, C McKnight.
Defiance Co.
09/07/2016. Maumee R., 41.2867, -84.4381, MJ Bolton.
Delaware Co.
09/01/2016. Olentangy R., 40.257383, -83.06203, MJ Bolton.
Erie Co.
08/25/2018. Huron R., 41.2908, -82.6375, C McKnight.
Fairfield Co.
08/22/2011. Scippo Cr., 39.5397, -82.8456, J Freda.
Fayette Co.
08/29/2011. Deer Cr., 39.659761, -83.26301, C McKnight.
Franklin Co.
09/08/2016. Scioto R., 39.9583, -83.0044, MJ Bolton.
Fulton Co.
08/27/2013. Bean Cr., 41.6231, -84.2961, MJ Bolton.
Gallia Co.
08/01/2017. Symmes Cr., 38.7672, -82.4369, E Moore.
Geauga Co.
08/27/2018. W.Br. Cuyahoga R., 41.4878, -81.1743, C McKnight.
Greene Co.
09/22/2011. Little Miami R., 39.6914, -84.0286, A Dripps.
Guernsey Co.
09/09/2014. Leatherwood Cr., 40.021046, -81.56585, MJ Bolton.
Hamilton Co.
10/03/2018. Whitewater R., 39.1831, -83.7928, MJ Bolton.
Hardin Co.
07/07/2011. Scioto R., 40.6369, -83.5986, J Freda.
Harrison Co.
08/24/2016. Conotton Cr., 40.4178, -81.1464, S Macy.
Henry Co.
09/06/2016. Maumee R., 41.3206, -84.2, C McKnight.
Holmes Co.
08/24/2017. Middle Fk. Sugar Cr., 40.6406, -81.6756, C McKnight.
Huron Co.
09/21/2016. W.Br. Huron R., 41.2808, -82.6756, C McKnight.
Jackson Co.
09/07/2016. Little Raccoon Cr., 39.0094, -82.445, M Gray.
Jefferson Co.
08/11/2011. Yellow Cr., 40.5379, -80.725, J Freda.
Lake Co.
09/20/2017. Grand R., 41.7261, -81.2383, MJ Bolton.
Lawrence Co.
08/24/2016. Symmes Cr., 38.4847, -82.455, E Moore.
Logan Co.
08/07/2014. Big Darby Cr., 40.3156, -83.5919, E Moore.
Lorain Co.
09/10/2015. Black R., 41.379316, -82.10772, MJ Bolton.
Lucas Co.
09/28/2016. Maumee R., 41.4142, -83.8606, C McKnight.
Madison Co.
08/26/2014. Big Darby Cr., 40.091308, -83.25552, C McKnight.
Mahoning Co.
09/18/2013. Mahoning R., 41.0761, -80.6161, A Dripps.
Medina Co.
09/10/2014. N.Br. Rocky R., 41.1525, -81.8222, A Dripps.
Meigs Co.
09/15/2015. Shade R., 39.094478, -81.85316, C McKnight.
Miami Co.
08/24/2015. Stillwater R., 39.98531, -84.31457, C McKnight.
Montgomery Co.
09/13/2016. Great Miami R., 39.6406, -84.2922, C McKnight.
Morgan Co.
09/12/2013. Olive Green Cr., 39.65538, -81.60548, E Moore.
Noble Co.
08/20/2014. Buffalo Cr., 39.858815, -81.52295, L Hughes.
Paulding Co.
09/13/2017. Little Auglaize R., 41.0486, -84.3889, MJ Bolton.
Pickaway Co.
09/05/2014. Big Darby Cr., 39.6778, -83.0964, C McKnight.
Pike Co.
10/11/2011. Scioto R., 39.0978, -82.9747, , -822.9747, C McKnight.
Portage Co.
08/28/2018. Breakneck Cr., 41.1394, -81.2708, C McKnight.
Putnam Co.
09/07/2016, Auglaize R., 41.0208, -83.2889, S Macy.
Ross Co.
09/19/2011. Scioto R., 39.1872, -82.83, C McKnight.
Scioto Co.
09/22/2011. Scioto R., 38.785, -82.9858, J Freda.
Stark Co.
08/28/2019. Tuscarawas R., 40.8069, -81.5272, E Moore.
Summit Co.
09/06/2018. Yellow Cr., 41.163527, -81.57627, C McKnight.
Trumbull Co.
09/19/2013. Mahoning R., 41.2439, -80.865, A Dripps.
Tuscarawas Co.
09/28/2017. Tuscarawas R., 40.655, -81.4453, MJ Bolton.
Union Co.
08/25/2014. Big Darby Cr., 40.124, -83.2725, C McKnight.
Van Wert Co.
08/27/2014. Dog Cr., 40.9036, -84.4433, C McKnight.
Vinton Co.
08/24/2016. Elk Fork, 39.2167, -82.4049, M Gray.
Warren Co.
09/14/2016. Great Miami R., 39.5631, -84.305, C McKnight.
Washington Co.
09/11/2013. Aldridge Run, 39.483978, -81.79267, E Moore.
Wayne Co.
09/13/2017. Sugar Cr., 40.75, -81.6708, C McKnight.
Williams Co.
09/26/2013. St. Joseph R., 41.4892, -84.7306, L Hughes.
Wood Co.
08/29/2012. Maumee R., 41.548042, -83.67494, C McKnight.

Terminal Flat-headed Mayfly Stenonema terminatum (Walsh, 1862) [ listed as Maccaffertium terminatum by Mayfly Central]

First collection, most recent collection, location, collector:

First
1958. Champaign Co. (Mad R.), Gaufin (1958).
Allen Co.
09/09/2019. Auglaize R., 40.7078, -84.2733, C McKnight.
Ashtabula Co.
09/14/2015. Conneaut Cr., 41.9271, -80.6043, S Macy.
Auglaize Co.
09/09/2019, Auglaize R., 40.6681, -84.2717, C McKnight.
Brown Co.
08/23/2012. E.Fk. Little Miami R., 39.137974, -84.00284, E Moore.
Butler Co.
09/14/2016. Great Miami R., 39.4814, -84.4428, MJ Bolton.
Carroll Co.
08/03/2010. Sandy Cr., 40.7167, -81.1097, D Eicher.
Clark Co.
08/22/2011. N. Fk. Little Miami R., 39.8081, -83.79, C McKnight.
Clermont Co.
10/26/2012. E. Fk. Little Miami R., 39.0589, -84.0517, E Moore.
Coshocton Co.
09/27/2017. Tuscarawas R., 40.2919, -81.75, C McKnight.
Crawford Co.
09/19/2011. Sandusky R., 40.8383, -82.8556, MJ Bolton.
Cuyahoga Co.
09/05/2015. Tinkers Cr., 41.364894, -81.60862, C McKnight.
Darke Co.
09/04/2013. Stillwater R., 40.1867, -84.4733, C McKnight.
Defiance Co.
09/07/2016. Maumee R., 41.2867, -84.4381, MJ Bolton.
Delaware Co.
08/31/2016. Olentangy R., 40.324253, -83.07077, MJ Bolton.
Erie Co.
08/25/2018. Huron R., 41.3017, -82.6069, C McKnight.
Fayette Co.
08/29/2011. Deer Cr., 39.659761, -83.26301, C McKnight.
Franklin Co.

Flat-headed Mayfly Macdunnoa persimplex (MacDunnough, 1929)

First collection, most recent collections, locations, collectors:

06/01/1976. Brown Co. Ohio River. DC Beckett (Flowers, 1982; Bolton, et al., 2019)

09/08/2016. Scioto R., 39.9583, -83.0044, MJ Bolton.
Fulton Co.
08/27/2013. Bean Cr., 41.6231, -84.2961, MJ Bolton.
Gallia Co.
09/26/2016. Raccoon Cr., 38.803802, -82.3708, L Hughes.
Geauga Co.
08/30/2012. E. Br. Chagrin R., 41.600913, -81.29087, J Freda.
Greene Co.
09/22/2011. Little Miami R., 39.70738, -83.99127, C McKnight.
Guernsey Co.
09/18/2014. Wills Cr., 40.168242, -81.64863, L Hughes.
Hamilton Co.
10/03/2018. Whitewater R., 39.1831, -83.7928, MJ Bolton.
Hardin Co.
08/18/2011. Taylor Cr., 40.6378, -83.6172, J Freda.
Henry Co.
09/06/2017. Maumee R., 40.3206, -84.2, C McKnight.
Holmes Co.
09/12/2017. Walnut Cr., 40.5614, -81.6747, C McKnight.
Huron Co.
09/21/2016. W.Br. Huron R., 41.2867, -82.6428, C McKnight.
Lake Co.
09/20/2017. E. Br. Chagrin R., 41.5897, -81.2994, E Moore.
Lawrence Co.
08/24/2016. Symmes Cr., 38.4847, -82.455, E Moore.
Lorain Co.
09/10/2015. Black R., 41.379316, -82.10772, MJ Bolton.
Lucas Co.
09/25/2013. Maumee R., 41.4142, -83.8606, MJ Bolton.
Madison Co.
08/20/2014. Little Darby Cr., 39.918162, -83.25992, E Moore.
Mahoning Co.
09/17/2013. Mahoning R., 41.105, -80.6638, A Dripps.
Mercer Co.
09/08/2016. St. Marys R., 40.6811, -84.5806, C McKnight.
Miami Co.
08/24/2015. Stillwater R., 39.98531, -84.31457, C McKnight.
Monroe Co.
09/09/2015. Clear Fork, 39.6025, -81.1628, L Hughes.
Montgomery Co.
09/13/2016. Great Miami R., 39.6406, -84.2922, C McKnight.
Paulding Co.
09/26/2017. Middle Cr., 41.019367, -84.42925, S Macy.
Pickaway Co.
09/08/2016. Scioto R., 39.6014, -82.9553, S Macy.
Pike Co.
10/11/2011. Scioto R., 39.0978, -82.9747, -822.9747, C McKnight.
Portage Co.
08/14/2018. Breakneck Cr., 41.169486, -81.33769, C McKnight.
Preble Co.
09/20/2017. E. Fk. Whitewiater R., 39.8664, -84.7908, MJ Bolton.
Putnam Co.
08/05/2019, Jennings Cr., 40.8631, -83.3393, C McKnight.
Ross Co.
09/09/2016. Scioto R., 39.3469, -82.9836, MJ Bolton.
Scioto Co.
09/08/2016. Scioto R., 38.8333, -83.0183, L Hughes.
Stark Co.
08/28/2019. Tuscarawas R., 40.8069, -81.5272, E Moore.
Summit Co.
09/06/2018. Furnace Run, 41.201516, -81.57335, C McKnight.
Trumbull Co.
09/19/2013. Mahoning R., 41.2439, -80.865, A Dripps.
Tuscarawas Co.
09/28/2017. Tuscarawas R., 40.6092, -81.4286, C McKnight.
Union Co.
08/18/2014. Little Darby Cr., 40.1158, -83.425, E Moore.
Van Wert Co.
08/06/2019. Jennings Cr., 40.8597, -84.3422, C McKnight.
Warren Co.
09/14/2016. Great Miami R., 39.5631, -84.305, C McKnight.
Williams Co.
09/26/2013. St. Joseph R., 41.4892, -84.7306, L Hughes.
Wood Co.
09/15/2015. Jackson Cutoff Ditch, 41.3428, -83.8461, E Moore.

March Flat-headed Mayfly Stenonema vicarium (Walker, 1853) [ listed as Maccaffertium vicarium by Mayfly Central]

First collection, most recent collection, location, collector:

First
1935. Lake Co., Traver (1935).
Adams Co.
07/16/2019. Puntennehy Run, 38.71226, -83.38903, MJ Bolton.
Ashtabula Co.
09/17/2015. Conneaut Cr., 41.9039, -80.5294, S Macy.
Athens Co.
07/27/2017, Hewett Fork, 39.3175, -82.2781, C McKnight.
Brown Co.
08/23/2012. E.Fk. Little Miami R., 39.137974, -84.00284, E Moore.
Belmont Co.
06/16/2015. Salt Fk. Wills Cr., 40.00074, -81.22005, MJ Bolton.
Butler Co.
09/09/2012. Elk Cr., 39.5275, -84.4675, C McKnight.
Carroll Co.
09/21/2016. Dining Fork, 40.4608, -81.0316, S Macy.
Champaign Co.
08/21/2014. Pleasnt Run., 40.2143, -83.4977, C McKnight.
Coshocton Co.
09/27/2017. W. Fk. White Eyes Cr., 40.3314, -81.7431, C McKnight.
Cuyahoga Co.
09/20/2017. Chagrin R., 41.517731, -81.40342, C McKnight.
Darke Co.
07/31/2018. Brinley Fork, 39.891716, -84.75044, S Macy.
Fairfield Co.
06/22/2017. Fetters Run, 39.729764, -82.58412, S Macy.
Franklin Co.
08/27/2017. Big Darby Cr., 39.9817, -83.2494, E Moore.
Gallia Co.
06/20/2017. Georges Cr., 38.617444, -82.30541, C McKnight.
Geauga Co.
09/12/2018. W. Br. Cuyahoga R., 41.560832, -81.15644, E Moore.
Greene Co.
09/22/2011. Little Miami R., 39.6986, -84.0194, M Gray.
Guernsey Co.
04/15/2016. Trib. Salt Fork, 40.0049, -81.2316, MJ Bolton.
Harrison Co.
09/20/2016. Kirby Run, 40.4315, -81.085, S Macy.
Highland Co.
07/18/2018. Trib. Rattlesnake Cr., 39.27337, -83.41993, MJ Bolton.
Hocking Co.
08/09/2018. Trib. Queer Cr., 39.438606, -82.5376, MJ Bolton.
Holmes Co.
08/12/2019. Trib. Indian Trail Cr., 40.58, -81.7242, E Moore.
Huron Co.
08/31/2016. E.Br. Huron R., 41.1769, -82.6531, C McKnight.
Jackson Co.
09/14/2011. Salt Lick Cr., 39.0981, -82.665, C McKnight.
Jefferson Co.
08/11/2011. Yellow Cr., 40.5379, -80.725, J Freda.
Knox Co.
05/16/2013. Primary Headwatefs to Little Jelloway Cr., 40.465611, -82.34019, C McKnight.
Lake Co.
09/05/2018. Trib Pierson Cr., 41.61526, -81.31262, MJ Bolton.
Lawrence Co.
07/03/2017. Little Indian Guyan Cr., 38.581354, -82.37699, C McKnight.
Licking Co.
10/17/2017. Quarry Run, 39.969217, -82.39423, S Macy.
Logan Co.
09/08/2014. Little Darby Cr., 40.282375, -83.59415, E Moore.
Lorain Co.
09/01/2015. Beaver Cr., 41.4169, -82.2258, S Macy.
Madison Co.
08/18/2014. Little Darby Cr., 39.946162, -83.28132, E Moore.
Mahoning Co.
09/19/2013. Meander Cr., 41.0478, -80.8275, A Dripps.
Medina Co.
09/26/2017. Johnson's Cr., 41.2165, -81.7141, DH Dean.
Meigs Co.
09/22/2015. W.Br. Shade R., 39.135599, -81.99724, C McKnight.
Miami Co.
08/20/2013. Stillwater R., 40.1597, -84.4011, C McKnight.
Monroe Co.
09/10/2015. Whitten Run, 39.6006, -81.2092, L Hughes.
Montgomery Co.
09/07/2010. Wolf Cr., 39.77037, -84.2473, C McKnight.
Morgan Co.
09/19/2013. Sharon Fork, 39.663776, -81.60498, E Moore.
Muskingum Co.
09/25/2014. White Eyes Cr., 40.134658, -81.73598, L Hughes.
Noble Co.
08.29.2014. Buffalo Cr., 39.823781, -81.73598, L Hughes
Pickaway Co.
07/31/2018. Trib. Slate Run, 39.756906, -82.84201, MJ Bolton.
Pike Co.
08/16/2016. Georges Run, 39.05087, -83.19202, MJ Bolton.
Portage Co.
08/14/2018. Tinkers Cr., 41.215725, -81.37301, C McKnight.
Preble Co.
10/03/2018. E. Fk. Whitewater R., 39.8439, -84.8053, MJ Bolton.
Ross Co.
09/14/2011. Hickson Run, 39.172398, -82.83582, C McKnight.
Scioto Co.
09/12/2018. Trib Odell Cr., 38.73588, -83.1174, MJ Bolton.
Stark Co.
08/24/2017. Pigeon Run, 40.764, -81.5581, E Moore.
Summit Co.
07/30/2019. Dickerson Run, 41.2184, -81.552, E Moore.
Tuscarawas Co.
09/27/2017. Stone Cr., 40.478196, -81.48307, C McKnight.
Union Co.
08/13/2014. Big Darby Cr., 40.2497, -83.5331, E Moore.
Vinton Co.
07/316/2017. Hewett Fork, 39.304465, -82.32265, C McKnight.
Warren Co.
09/19/2011. Little Miami R., 39.5164, -84.0933, MJ Bolton.
Washington Co.
08/28/2018. Hog Run, 39.485903, -81.27044, MJ Bolton.
Wayne Co.
08/22/2017. Sugar Run, 40.7838, -81.7297, C McKnight.
Williams Co.
09/16/2013. Nettle Cr., 41.6722, -84.6889, L Hughes.

Carolina Flat-headed Mayfly Stenacron carolina (Banks, 1914)

First collection, most recent collection, location, collector:

1976. Athens Co. (Sugar Cr.), Napier & Hummon (1976).
1998. Geauga Co., U.S. Nat'l. Museum)
Not classified beyond genus by Ohio EPA

Gildersleeve's Stenacron Mayfly Stenacron gildersleevei (Traver, 1935)

First collection, most recent collection, location, collector:

1935. Lake Co., Kirkland, (E. Br. Chagrin R.), Traver (1935).
1974. Lake Co. (trib. Chagrin R.), Lewis (1974)

Not classified beyond genus by Ohio EPA

Common Flat-headed Mayfly Stenacron interpunctatum (Say, 1839)

First collection, most recent collection, location, collector:

First 1935. Lake Co. (East Cr.), Traver (1935).
Other Records from Randolph and McCafferty (1998)
1942. Ottowa Co. (Lake Erie), Shelford & Boesel (1942).
1958. Champaign Co. (Mad. R.), Gaufin (1958).
1974. Clermont Co. (Little Miami R., Shayler Run Cr.), Dark Co. (Stillwater R.), Hamilton Co. (Little Miami R., Ohio R.), Knox Co. (Mohican R.), Lake Co. (Chagrin R., Paine Cr.), Pike Co. (White Lake), Lewis (1974).
1976. Athens Co. (Margaret Cr., Sugar Cr., Strouds Run), Napier & Hummor (1976).
1981. Madison Co. (Big Darby Cr.), Lamp & Britt (1981).
1984. Lake Co. (Stony Brook), Roberson (1984).
1985. Adams Co. (Ohio Brush Cr.), Ashland Co. (Clear Fork Mohican R.), Belmont Co. (Captina Cr.), Gallia Co. (Tycoon Lake), Guernsey Co. (Seneca Fork Wills Cr.), Hocking Co. (Clear Cr., Hocking R.), Jefferson Co., Monroe Co. (Sunfish Cr.), Morgan Co., Muskingum Co. (Little Muskingum R.), Hall (1985).
1998. Highland Co. (Paint Cr.), Scioto Co. (East Fork Cr., Pond Lick Cr.), Colorado State U.; Ashtabula Co. (Indian Cr.), Brown Co. (Big Three Mile , Eagle Cr., E. Fork Little Miami R., W. Fork Cr., White Oak Cr.), Champaign Co. (Nettles Cr., trib. Graves Cr.), Clark Co. (Beaver Cr, N. Fork Little Miami R.), Clinton Co. (Todd Fork), Cuyahoga Co., Delaware Co. (Alum Cr., Bokes Cr, Dun Run, Fulton Cr., Sugar Cr.), Franklin Co. (Big Darby Cr., Scioto R.), Green Co. (Jacoby Branch Little Miami R., Ludlow Cr., Massies Cr., N & S Branch Caesar Cr., Shawnee Cr.), Logan Co. (Bakengehalas Cr., Muchinippi Cr., trib. Mad R.), Marion Co. (Beaver Run, Indigo Cr., McDonald Cr., Rush Cr., Scioto R.) Medina Co. (E. Br. Black R., trib. Black R.), Miami Co. (Canyon Run, Greeneville Cr., Harris cr., Ludlow Cr. Stillwater R., trib. Honey Cr.), Morrow Co. (Alum Cr.), Prebel Co. (E. Fork Formile Cr., E. Fork Whitewater R., Goose Cr., Price Cr. Seven Mile Cr., Swamp Cr., trib. Little Four Mile Cr.), Sandulsk Co. (E. Br. Wolf R., Sandulsky R., W. Fork Wolf Cr., Wolf Cr.), Seneca Co. (Beaver Cr.), Shelby Co. (Brush Cr., Leatherwood Cr., Mill branch), Trumbull Co. (Mahoning R., Mill Cr.), Union Co. (Mill Cr.), Warren Co. (Little Run Todd Fork), Ohio Biol. Survey; Miami Co. (Spring Cr.), Montgomery Co. (Miami R.), Selby Co. (Miami R.), Warren Co. (Little Miami R.), Purdue Entomol. Res. Ctr.; Geauga Co., U.S. Nat'l. Museum. Vinton Co. is shown on map (Fig. 156) and Lawrence Co. (Fig. 156) of Randolph & McCafferty (1998), but not in text.
06/15/2013. Wayne Co. (Apple Cr. 40.7915, -81.93048), DH Dean

Minnetonka Flat-headed Mayfly Stenacron minnitonka (Daggy, 1945)

First collection, most recent collection, location, collector:
First
1974. Clermont Co. (Kain Run, Little Miami R), Lewis (1974).
Not classified beyond genus by Ohio EPA

Red Fox Flat-headed Mayfly Stenonema femoratum (Say, 1823)

First collection, most recent collection, location, collector:

First
1823. Hamilton Co., as Baetis femorata, Say (1823).
Co.
Adams Co.
08/24/2016. E.Fk. Eagle Cr., 38.7955, -83.6539, MJ Bolton.
Allen Co.
09/09/2019. Auglaize R., 40.7078, -84.2733. C McKnight.
Ashtabula Co.
08/07/2018. Trib. Shenango R., 41.56049, -80.52975, S Macy.
Athens Co.
07/27/2017. Hewett Fork, 39.3175.-82.2781, C McKnight.
Auglaize Co.
09/09/2019. Auglaize R., 40.6681, -84.2717, C McKnight.
Belmont Co.
10/13/2010. Captina Cr., 39.9111, -81.0036, A Dripps.
Brown Co.
08/23/2016. Eagle Cr., 38.75, -83.7672, MJ Bolton.
Butler Co.
07/10/2018. Sater Run, 39.368211, -84.81065. S Macy.
Carroll Co.
08/03/2010. Sandy Cr., 40.7178, -81.1072, D Eicher.
Champaign Co.
08/21/2014. Pleasant Run, 40.2143, -83.4977, C McKnight.
Clark Co.
08/22/2011. Little Miami R., 39.8325, -83.6944, A Dripps.
Clermont Co.
07/30/2018. Trib. O'Bannon Cr., 39.257626, -84.22607, C McKnight.
Clinton Co.
07/27/2018. Trib. Cowan Cr., 39.38591, -83.88057, C McKnight.
Columbiana Co.
08/23/2010. Middle Br. Sandy Cr., 40.751572, -81.06938, D Eicher.
Coshocton Co.
09/26/2017. Tuscarawas R., 40.2767, -81.6506, C McKnight.
Crawford Co.
09/11/2018. Broken Sword Cr., 40.888957, -82.87771, C McKnight.
Cuyahoga Co.
07/30/2019. Sagamore Cr., 41.3514, -81.5923, E Moore.
Darke Co.
08/06/2019. Welker Lateral, 39.9531. -84.7049, E Moore.
Defiance Co.
07/19/2016. Platter Cr., 41.28163, -84.6239, E Moore.
Delaware Co.
09/12/2018. Barthomew Run, 40.151163, -83.05351, C McKnight.
Erie Co.
08/25/2016. Huron R., 41.2908, -82.6375, C McKnight.
Fairfield Co.
08/23/2019. Sycamore Cr., 39.9292, -82.7242, MJ Bolton.
Fayette Co.
07/20/2011. Duffs Fork, 39.656461, -83.27162, C McKnight.
Franklin Co.
08/15/2018. Linworth Run. 40.093163, -83.04961, C McKnight.
Fulton Co.
06/28/2017. AI Cr., 41.5957, -83.8976, MJ Bolton.
Gallia Co.
08/14/2017. Indian Guyan Cr., 38.597159, -82.31897, C McKnight.
Geauga Co.
09/12/2018. W.Br. Cuyahoga R., 41.560832, -81.15644, E Moore.
Greene Co.
09/12/2041. Salt Fk. Wills Cr., 39.6583, -84.0417, M Gray.
Guernsey Co.
09/12/2014. Salt Fk. Wills Cr., 40.0578, -81.4147, L Hughes.
Hamilton Co.
08/06/2019. Howard Cr., 39.30483, -84.76289, E Moore.
Hancock Co.
09/14/2017. Brights Ditch., 41.0049, -83.5546, MJ Bolton.
Hardin Co.
07/03/2017. Rickenbach Ditch, 40.8325, -83.471, MJ Bolton.
Harrison Co.
08/28/2012. Laurel Cr., 40.30207, -81.32765, MJ Bolton.
Henry Co.
09/06/2016. Maumee R., 41.3206, -84.2, C McKnight.
Highland Co.
06/27/2016. Puncheon Run, 39.198871, -83.41355, MJ Bolton.
Hocking Co.
08/09/2018. Trib. Queer Cr., 39.438606, -82.5376, MJ Bolton.
Holmes Co.
07/17/2017. Goose Cr., 40.545, -81.6939, C McKnight.
Huron Co.
09/21/2016. W.Br. Huron R., 41.2808, -82.6756, C McKnight.
Jackson Co.
09/06/2016. Cherry Fork, 38.896088, -82.48693, C McKnight.
Jefferson Co.
08/11/2011. Yellow Cr., 40.5379, -80.725, J Freda.
Lake Co.
09/05/2018. Trib. Pierson Cr., 41.60915, -81.30811, MJ Bolton.
Lawrence Co.
07/03/2017. Little Indian Guyan Cr., 38.581354, -82.37699, C McKnight.
Licking Co.
10/17/2017. Quarry Run, 39.969217, -82.39423, S Macy.
Logan Co.
09/132017. near Mad R., 40.334202, -83.679531, (adult), DH Dean.
Lorain Co.
09/10/2015. Black R., 41.379316, -82.10772, MJ Bolton.
Lucas Co.
08/22/2018. Tenmile Cr., 41.6883, -83.735, C McKnight.
Madison Co.
09/22/2014. Big Darby Cr., 40.0694, -83.2492, MJ Bolton.
Mahoning Co.
09/18/2013. Mahoning R., 41.0761, -80.6161, A Dripps.
Medina Co.
01/26/2018. Johnson's Cr., 41.2165, -81.7141, DH Dean.
Meigs Co.
08/18/2016. Strongs Run, 39.0703, -82.3028, M Gray.
Mercer Co.
09/14/2015. St. Marys R., 40.6811, -84.5806, C McKnight.
Miami Co.
10/14/2015. Harris Run, 40.1403, -84.3742, E Moore.
Monroe Co.
09/10/2015. Witten Run, 39.6006, -81.2092, L Hughes.
Montgomery Co.
09/13/2016. Great Miami R., 39.6744, -84.2617, E Moore.
Morgan Co.
10/02/2013. Peeper Run, 39.678215, -82.00336, MJ Bolton.
Muskingum Co.
07/02/2014. Fox Cr., 39.992033, -81.7431, MJ Bolton.
Noble Co.
08/28/2018. Trib. Wolf Run, 39.8053, -81.5158, MJ Bolton.
Ottawa Co.
09/07/2017. Toussant Cr., 41.5014, -83.3383, MJ Bolton.
Paulding Co.
07/30/2019. Prairie Cr., 41.1003, -84.3805, C McKnight.
Pickaway Co.
07/31/2018. Trib. Slate Run, 39.756906, -82.84201, MJ Bolton.
Pike Co.
08/16/2016. Long Run, 39.038386, -83.24103, MJ Bolton.
Portage Co.
07/13/2018. Trib. Cuyahoga R., 41.2409974, -81.30107, MJ Bolton.
Preble Co.
10/03/2018. E.Fk. Whitewater R., 39.8439, -84.8053, MJ Bolton.
Putnam Co.
07/19/2019. Big Run, 40.9037, -84.2781, C McKnight.
Richland Co.
07/05/2016. W.Br. Huron R., 40.995, -82.6517, C McKnight.
Ross Co.
09/14/2011, Hickson Run, 39.172398, -82.83582, C McKnight.
Scioto Co.
09/08/2016. Scioto R., 39.8333, -83.0183, L Hughes.
Seneca Co.
06/22/2016. Mud Run, 41.1161, -82.8422, C McKnight.
Shelby Co.
07/02/2015. Turtle Cr., 40.33, -84.2534, A Dripps.
Stark Co.
08/28/2019. Tuscarawas R., 40.8069, -81.5272, E Moore.
Summit Co.
07/30/2019. Dickerson Run, 41.2184, -81.552, E Moore.
Trumbull Co.
10/01/2013. Mosquito Cr., 41.2506, -80.7633, A Dripps.
Tuscarawas Co.
09/12/2017. Sugar Cr., 40.6361, -81.5533, C McKnight.
Union Co.
08/13/2015. Town Run, 40.2292, -83.365, MJ Bolton.
Van Wert Co.
08/01/2019. West Jenning Cr., 40.824171, -84.37869, C McKnight.
Vinton Co.
07/13/2017. Elk Fork, 39.2467, -82.4602, C McKnight.
Warren Co.
08/06/2018. Trib. Muddy Cr., 39.366116, -84.29266, C McKnight.
Washington Co.
08/28/2018. Hog Run, 39.485903, -8127044, MJ Bolton.
Wayne Co.
09/13/2017. Sugar Cr., 40.75, -81.6708, C McKnight.
Williams Co.
09/26/2013. St. Joseph R., 41.4892, -84.7306, L Hughes.
Wood Co.
09/07/2017. Cedar Cr., 41.589499, -83.47387, MJ Bolton.

Spotted Flat-headed Mayfly Stenonema mediopunctatum (McDunnough, 1926)[listed as Maccaffertium mediopunctatum by Mayfly Central]

First collection, most recent collection, location, collector:

First
1935 Lake Co. (Chagrin R.) as Stenonema nepotellum, Traver (1935).
Ashtabula Co.
09/17/2015. Conneaut Cr., 41.9039, -80.5294, S Macy.
Auglaize Co.
09/06/2019. Auglaize R., 40.5811, -84.175, C McKnight.
Butler Co.
09/21/2017. Dry Fk. Whitewater R., 39.3269, -84.7486, S Macy.
Carroll Co.
08/04/2010. Sandy Cr., 40.6997, -81.1506, C McKnight.
Champaign Co.
08/21/2014. Pleasant Run, 40.2143, -83.4977, C McKnight.
Columbiana Co.
06/17/2010. Conser Run, 40.7575, -81.0303, D Eicher.
Coshocton Co.
08/10/2016. Muskingum R., 40.2361, -81.8717, MJ Bolton.
Darke Co.
09/04/2013. Stillwater R., 40.1908, -84.5256, C McKnight.
Franklin Co.
09/03/2014. Little Darby Cr., 39.893662, -83.21881, E Moore.
Fulton Co.
08/27/2013. Bean Cr., 41.6231, -84.2961, MJ Bolton.
Greene Co.
09/22/2001. Little Miami R., 39.6914, -84.0286, A Dripps.
Hamilton Co.
10/03/2018. Whitewater R., 39.1831, -84.7928, MJ Bolton.
Hardin Co.
07/07/2011. Scioto R., 40.6372, -83.5733, J Freda.
Huron Co.
08/31/2016. E.Br. Huron R., 41.2756, -82.6369, C McKnight.
Jefferson Co.
07/21/2010. Grassy Run, 40.39152, -81.81533, M Gray.
Lake Co.
09/20/2017. E.Br. Chagrin R., 41.5897, -81.2994, E Moore.
Madison Co.
09/22/2014. Big Darby Cr., 40.0694, -83.2492, MJ Bolton.
Miami Co.
08/24/2015. Stillwater R., 39.98531, -84.31457, C McKnight.
Montgomery Co.
09/13/2016. Great Miami R., 39.6406, -84.2922, C McKnight.
Preble Co.
10/03/2018. E.Fk. Whitewater R., 39.8439, -84.8053, MJ Bolton.
Union Co.
09/25/2014. Big Darby Cr., 40.1353, -83.32, MJ Bolton.
Warren Co.
09/14/2016. Great Miami R., 39.5631, -84.305, C McKnight.
Williams Co.
09/25/2013. St. Joseph R., 41.435398, -84.74564, L Hughes.