Northeastern Hammertail
Efferia aestuans (Linnaeus, 1763)
Northeastern Hammertail in all of OhioRange
Where it is recorded
Season shown in 11 of Ohio's 88 counties. Explore Ohio
- No result yet (30)
- Recorded, too few records for a result (47)
- Recorded, season not shown (0)
- Season shown (11)
Counties as a table
| County | Records |
|---|---|
| Adams County | Recorded, too few records for a result |
| Allen County | Recorded, too few records for a result |
| Ashland County | Recorded, too few records for a result |
| Ashtabula County | 24 · Season shown |
| Athens County | Recorded, too few records for a result |
| Auglaize County | No qualifying records yet |
| Belmont County | Recorded, too few records for a result |
| Brown County | Recorded, too few records for a result |
| Butler County | Recorded, too few records for a result |
| Carroll County | Recorded, too few records for a result |
| Champaign County | No qualifying records yet |
| Clark County | Recorded, too few records for a result |
| Clermont County | 20 · Season shown |
| Clinton County | Recorded, too few records for a result |
| Columbiana County | Recorded, too few records for a result |
| Coshocton County | No qualifying records yet |
| Crawford County | Recorded, too few records for a result |
| Cuyahoga County | 29 · Season shown |
| Darke County | Recorded, too few records for a result |
| Defiance County | No qualifying records yet |
| Delaware County | Recorded, too few records for a result |
| Erie County | Recorded, too few records for a result |
| Fairfield County | Recorded, too few records for a result |
| Fayette County | No qualifying records yet |
| Franklin County | 22 · Season shown |
| Fulton County | Recorded, too few records for a result |
| Gallia County | Recorded, too few records for a result |
| Geauga County | Recorded, too few records for a result |
| Greene County | Recorded, too few records for a result |
| Guernsey County | No qualifying records yet |
| Hamilton County | 21 · Season shown |
| Hancock County | Recorded, too few records for a result |
| Hardin County | Recorded, too few records for a result |
| Harrison County | No qualifying records yet |
| Henry County | No qualifying records yet |
| Highland County | Recorded, too few records for a result |
| Hocking County | Recorded, too few records for a result |
| Holmes County | Recorded, too few records for a result |
| Huron County | Recorded, too few records for a result |
| Jackson County | No qualifying records yet |
| Jefferson County | Recorded, too few records for a result |
| Knox County | Recorded, too few records for a result |
| Lake County | 43 · Season shown |
| Lawrence County | Recorded, too few records for a result |
| Licking County | Recorded, too few records for a result |
| Logan County | No qualifying records yet |
| Lorain County | Recorded, too few records for a result |
| Lucas County | 66 · Season shown |
| Madison County | Recorded, too few records for a result |
| Mahoning County | Recorded, too few records for a result |
| Marion County | No qualifying records yet |
| Medina County | 23 · Season shown |
| Meigs County | No qualifying records yet |
| Mercer County | No qualifying records yet |
| Miami County | No qualifying records yet |
| Monroe County | No qualifying records yet |
| Montgomery County | 42 · Season shown |
| Morgan County | No qualifying records yet |
| Morrow County | Recorded, too few records for a result |
| Muskingum County | Recorded, too few records for a result |
| Noble County | No qualifying records yet |
| Ottawa County | No qualifying records yet |
| Paulding County | No qualifying records yet |
| Perry County | No qualifying records yet |
| Pickaway County | Recorded, too few records for a result |
| Pike County | No qualifying records yet |
| Portage County | Recorded, too few records for a result |
| Preble County | No qualifying records yet |
| Putnam County | No qualifying records yet |
| Richland County | Recorded, too few records for a result |
| Ross County | Recorded, too few records for a result |
| Sandusky County | No qualifying records yet |
| Scioto County | No qualifying records yet |
| Seneca County | Recorded, too few records for a result |
| Shelby County | No qualifying records yet |
| Stark County | 26 · Season shown |
| Summit County | 33 · Season shown |
| Trumbull County | Recorded, too few records for a result |
| Tuscarawas County | Recorded, too few records for a result |
| Union County | No qualifying records yet |
| Van Wert County | No qualifying records yet |
| Vinton County | Recorded, too few records for a result |
| Warren County | Recorded, too few records for a result |
| Washington County | No qualifying records yet |
| Wayne County | Recorded, too few records for a result |
| Williams County | No qualifying records yet |
| Wood County | Recorded, too few records for a result |
| Wyandot County | Recorded, too few records for a result |
No mapped range from the range source used, the USGS Gap Analysis Project, which maps land vertebrates only.
Season
When it is recorded
In Lake County
Early July to early September, middle week Aug 2–8
Records per week from 43 records in 9 of the 10 years from 2016 to 2025. Shows when people recorded it, not how common it is. The grey bars show how many records of all species were made here each week, so you can see when recording itself was high or low; the season is not adjusted by them.
Recorded on 39 dates. Latest record: September 2025.
Show as a table
| Week | Records of Northeastern Hammertail | Years recorded | Records of all species |
|---|---|---|---|
| Jan 4–10 | 0 | 0 | 54 |
| Jan 11–17 | 0 | 0 | 37 |
| Jan 18–24 | 0 | 0 | 52 |
| Jan 25–31 | 0 | 0 | 82 |
| Feb 1–7 | 0 | 0 | 58 |
| Feb 8–14 | 0 | 0 | 89 |
| Feb 15–21 | 0 | 0 | 51 |
| Feb 22–28 | 0 | 0 | 54 |
| Mar 1–7 | 0 | 0 | 51 |
| Mar 8–14 | 0 | 0 | 155 |
| Mar 15–21 | 0 | 0 | 190 |
| Mar 22–28 | 0 | 0 | 166 |
| Mar 29 – Apr 4 | 0 | 0 | 234 |
| Apr 5–11 | 0 | 0 | 425 |
| Apr 12–18 | 0 | 0 | 525 |
| Apr 19–25 | 0 | 0 | 522 |
| Apr 26 – May 2 | 0 | 0 | 844 |
| May 3–9 | 0 | 0 | 1,247 |
| May 10–16 | 0 | 0 | 647 |
| May 17–23 | 0 | 0 | 950 |
| May 24–30 | 0 | 0 | 1,067 |
| May 31 – Jun 6 | 0 | 0 | 1,073 |
| Jun 7–13 | 1 | 1 | 1,320 |
| Jun 14–20 | 0 | 0 | 1,088 |
| Jun 21–27 | 0 | 0 | 1,052 |
| Jun 28 – Jul 4 | 1 | 1 | 1,305 |
| Jul 5–11 | 6 | 4 | 1,359 |
| Jul 12–18 | 3 | 2 | 1,171 |
| Jul 19–25 | 2 | 2 | 1,056 |
| Jul 26 – Aug 1 | 8 | 4 | 1,193 |
| Aug 2–8 | 1 | 1 | 1,090 |
| Aug 9–15 | 4 | 4 | 745 |
| Aug 16–22 | 5 | 3 | 1,084 |
| Aug 23–29 | 5 | 4 | 847 |
| Aug 30 – Sep 5 | 2 | 2 | 699 |
| Sep 6–12 | 4 | 3 | 858 |
| Sep 13–19 | 0 | 0 | 714 |
| Sep 20–26 | 1 | 1 | 739 |
| Sep 27 – Oct 3 | 0 | 0 | 731 |
| Oct 4–10 | 0 | 0 | 723 |
| Oct 11–17 | 0 | 0 | 475 |
| Oct 18–24 | 0 | 0 | 425 |
| Oct 25–31 | 0 | 0 | 371 |
| Nov 1–7 | 0 | 0 | 271 |
| Nov 8–14 | 0 | 0 | 271 |
| Nov 15–21 | 0 | 0 | 197 |
| Nov 22–28 | 0 | 0 | 182 |
| Nov 29 – Dec 5 | 0 | 0 | 81 |
| Dec 6–12 | 0 | 0 | 111 |
| Dec 13–19 | 0 | 0 | 84 |
| Dec 20–26 | 0 | 0 | 96 |
| Dec 27 – Jan 2 | 0 | 0 | 289 |
Reported as an adult
Only 3 records here are marked as adults, too few to show a adult season. One needs at least 20 records from 5 different years.
Reported as a larva
No records here are marked as larvae yet, so there is no larva season to show. One needs at least 20 records from 5 different years.
In Ohio
Late June to early September, middle week Jul 26 – Aug 1
Records per week from 729 records in 10 of the 10 years from 2016 to 2025. Shows when people recorded it, not how common it is. The grey bars show how many records of all species were made here each week, so you can see when recording itself was high or low; the season is not adjusted by them.
Recorded on 402 dates. Latest record: September 2025.
Show as a table
| Week | Records of Northeastern Hammertail | Years recorded | Records of all species |
|---|---|---|---|
| Jan 4–10 | 0 | 0 | 6,211 |
| Jan 11–17 | 0 | 0 | 5,146 |
| Jan 18–24 | 0 | 0 | 4,645 |
| Jan 25–31 | 0 | 0 | 4,698 |
| Feb 1–7 | 0 | 0 | 6,023 |
| Feb 8–14 | 0 | 0 | 5,888 |
| Feb 15–21 | 0 | 0 | 5,436 |
| Feb 22–28 | 1 | 1 | 6,846 |
| Mar 1–7 | 0 | 0 | 8,321 |
| Mar 8–14 | 0 | 0 | 10,384 |
| Mar 15–21 | 0 | 0 | 12,620 |
| Mar 22–28 | 0 | 0 | 13,949 |
| Mar 29 – Apr 4 | 0 | 0 | 19,661 |
| Apr 5–11 | 0 | 0 | 26,860 |
| Apr 12–18 | 0 | 0 | 39,925 |
| Apr 19–25 | 0 | 0 | 41,623 |
| Apr 26 – May 2 | 0 | 0 | 56,391 |
| May 3–9 | 0 | 0 | 52,952 |
| May 10–16 | 0 | 0 | 53,785 |
| May 17–23 | 0 | 0 | 57,698 |
| May 24–30 | 0 | 0 | 54,651 |
| May 31 – Jun 6 | 1 | 1 | 53,099 |
| Jun 7–13 | 4 | 1 | 53,700 |
| Jun 14–20 | 4 | 4 | 56,625 |
| Jun 21–27 | 25 | 9 | 55,361 |
| Jun 28 – Jul 4 | 42 | 8 | 58,477 |
| Jul 5–11 | 64 | 10 | 61,336 |
| Jul 12–18 | 67 | 10 | 64,722 |
| Jul 19–25 | 92 | 8 | 69,753 |
| Jul 26 – Aug 1 | 83 | 9 | 59,416 |
| Aug 2–8 | 80 | 10 | 59,712 |
| Aug 9–15 | 78 | 10 | 55,994 |
| Aug 16–22 | 49 | 9 | 54,328 |
| Aug 23–29 | 53 | 9 | 51,772 |
| Aug 30 – Sep 5 | 44 | 9 | 57,167 |
| Sep 6–12 | 23 | 9 | 59,075 |
| Sep 13–19 | 7 | 5 | 54,543 |
| Sep 20–26 | 7 | 4 | 45,860 |
| Sep 27 – Oct 3 | 4 | 2 | 43,180 |
| Oct 4–10 | 1 | 1 | 37,841 |
| Oct 11–17 | 0 | 0 | 30,824 |
| Oct 18–24 | 0 | 0 | 21,156 |
| Oct 25–31 | 0 | 0 | 19,021 |
| Nov 1–7 | 0 | 0 | 14,172 |
| Nov 8–14 | 0 | 0 | 12,621 |
| Nov 15–21 | 0 | 0 | 7,965 |
| Nov 22–28 | 0 | 0 | 8,136 |
| Nov 29 – Dec 5 | 0 | 0 | 6,083 |
| Dec 6–12 | 0 | 0 | 6,004 |
| Dec 13–19 | 0 | 0 | 5,423 |
| Dec 20–26 | 0 | 0 | 5,661 |
| Dec 27 – Jan 2 | 0 | 0 | 8,459 |
Reported as an adult
Usually reported as an adult late June to early September, middle week Aug 2–8.
From 66 records that are marked as adults. Not every photo is marked with a life stage, so this shows when people reported it as an adult, not when adults are about.
Reported as a larva
No records here are marked as larvae yet, so there is no larva season to show. One needs at least 20 records from 5 different years.
What these results show
These results show when people recorded a species, not when or where it occurs. Missing weeks and low counts do not mean absence or scarcity, and counts are not abundance. Contributed records reflect where, when and what people chose to observe.
Identification
How to identify it
Often confused with
- Sand Hammertail Efferia albibarbis72 identifications worldwide named one where the other was meant
- Shiny-sided Bladetail Machimus sadyates65 identifications worldwide named one where the other was meant
- Maroon-legged Lion Fly Promachus hinei25 identifications worldwide named one where the other was meant
- Eastern Lion Fly Promachus rufipes16 identifications worldwide named one where the other was meant
- Asilus flavofemoratus Asilus flavofemoratus12 identifications worldwide named one where the other was meant
From iNaturalist’s similar-species counts, refreshed monthly: confusions in Ohio first, then worldwide. Only species with an Ohio result are listed.
Months not reported
- Jan: no record
- Feb: recorded
- Mar: no record
- Apr: no record
- May: recorded
- Jun: recorded
- Jul: recorded
- Aug: recorded
- Sep: recorded
- Oct: recorded
- Nov: no record
- Dec: no record
Not reported in Ohio in March to April and November to January, 2016 to 2025.
Land cover where it is recorded
| Land cover | Its recordsAll Ohio records |
|---|---|
| Developed | 66%49% |
| Forest | 15%31% |
| Farmland | 13%11% |
| Grassland and shrub | 5%0.9% |
| Wetland | 1%5% |
| Open water | 0.2%3% |
From 408 records placed within 100 m, beside all Ohio records placed the same way. People record where they go, so this shows where records come from, not where the species lives. Land cover: USGS Annual NLCD, 2025 (opens in a new tab)
Sources
Where these results come from
- Records from iNaturalist research-grade observations and expert-identified GBIF datasets, CC0, CC BY and CC BY-NC. Sources
- Seasons use the published method and its evidence thresholds. Methods
- See it on iNaturalist (opens in a new tab)OpenPhenology is independent and not affiliated with iNaturalist.
Records behind the Lake County result
43 records from 1 dataset.
- iNaturalist Research-grade Observations (opens in a new tab) · iNaturalist.org · 43 recordsiNaturalist contributors, iNaturalist (2026). iNaturalist Research-grade Observations. iNaturalist.org. Occurrence dataset https://doi.org/10.15468/ab3s5x accessed via GBIF.org on 2026-11-13.
To cite: the GBIF download doi:10.15468/dl.y2jkt8 (opens in a new tab).
A spreadsheet (CSV) with a link to each record, on iNaturalist or GBIF. Records whose location was hidden by the observer or the source are counted but not linked.