Evidence
Where all of this came from.
39 reference records rest on 224 published pages, and 109 of those come from state and provincial natural-resources departments. That suits a set of records about what lives in the water those departments survey. The rest is federal survey work, university and extension guides, and interagency reports. The counts are below. Every reviewed line sits behind a record or a search, with the sources standing behind its record.
How to read this
A line is cited as precisely as someone checked it.
Where a reviewer traced a line to the pages that carry it, the line names those pages and, when the evidence is narrower than the record, where it comes from — one coast, one lake, one region. 605 of 1049 of the lines below are traced that way. The rest show the sources standing behind their whole record, marked “record’s sources”, because nobody has yet checked which page carried which line, and printing a single citation there would be a mapping nobody made.
National
52
A federal or national government body — USGS, NOAA, EPA, the Fish and Wildlife Service, the Park Service, Fisheries and Oceans Canada.
State
109
A state, provincial or commonwealth natural-resources department. Most of this carrier rests here, which suits it: these are the bodies that survey the water the records describe.
Interagency
12
A commission or joint survey run across several agencies, such as the Great Lakes Fishery Commission's forage task groups.
University
45
A university research programme, cooperative extension service or Sea Grant office. Published work, but not the agency that manages the water.
Journal
6
A peer-reviewed paper, or a curated scientific register such as the World Register of Marine Species. Added with the 2026-09-25 evidence review, which went to the primary study where no agency page said what a claim needed.
Probe leftovers
What the weekly check could not treat as ordinary.
These addresses are still the citations. The check named what it saw. None of them is a gone page in the MISIN sense, so the records were not rewritten to hide a redirect, a timeout, or a bot wall.
Iowa DNR — BluegillMoved
The cited address answers through a permanent redirect. GET on the page that lands still names Bluegill.
A same-site move that still names the animal is not the MISIN case. The citation stays until a reviewer reads the new address into the record.
CASG — market squidUnreachable from this network
The California Sea Grant market-squid page times out from the probe network.
NOAA still covers the same animal on this record. The CASG address stays; a timeout is not a reason to drop a citation.
Mass.gov — menhaden and longfin squidRefused the probe
Both creature-feature pages answered 403 from the probe network.
A bot wall is not evidence the page is gone. The citations stay; the weekly check does not fail the build on unverifiable.
Michigan DNR — crayfish identification PDFRefused the probe
The cited PDF answered 403 from the probe network.
A refused PDF is not a 404. The citation stays on the crayfish record until a reviewer can open it.
Smithsonian Tropical Research Institute — silversidesRefused the probe
The Menidia page answered 500 from the probe network.
A 500 is not a 404, and it is not a 403. The citation stays.
Claims
Every reviewed line in the app.
Backswimmers →29 lines
- What you can seeSwims on its back, belly upwards — two independent sources state it, and it is the settled answerMDC-BACKSWIMMERS, EPA-MACRO-TIPSHEET, UF-BACKSWIMMER-EENY738
- What you can seeBack keeled like a hull, with no crosslines across itMDC-BACKSWIMMERS
- What you can seePiercing, tube-like mouthparts — a beak, not chewing jawsMDC-BACKSWIMMERS, PURDUE-HEMIPTERA
- What you can seeLarge eyes set close together on top of the headEPA-MACRO-TIPSHEET, MDC-BACKSWIMMERS
- What you can seeFront and middle legs built for grasping; hind legs long and oar-likeUWM-BOATMEN-BACKSWIMMERS, UF-BACKSWIMMER-EENY738, MDC-BACKSWIMMERS
- What you can seeA thin silvery bubble of air trapped against the bodyMDC-BACKSWIMMERS
- What argues against itSwimming right way up, with a flat back ruled by dark parallel crosslines and scoop-shaped front feet, is a water boatmanMDC-BACKSWIMMERS
- What argues against itHard wing covers meeting in a straight seam, with threadlike antennae you can see, is a diving beetleMDC-DIVING-BEETLES
- What argues against itHead-down at the surface with the tail tip out of the water does NOT settle it — a diving beetle rests in exactly the same posture, and sources describe both that wayMDC-BACKSWIMMERS, MDC-DIVING-BEETLES
- What argues against itCarrying a silvery air store does not settle it either. Both bugs and diving beetles do itMDC-BACKSWIMMERS, MDC-DIVING-BEETLES
- Declared limitSize is stated three incompatible ways — usually under half an inch, about 13 mm, and a bracket class of 15 to 29 mm. The band spans them.MDC-BACKSWIMMERS, PURDUE-HEMIPTERA, WVDEP-INVERT-GUIDE
- Declared limitThe most detailed account consulted covers a Eurasian species. Its air-film duration, temperature behaviour and one-brood-a-year seasonality are not offered here as North American facts.UF-BACKSWIMMER-EENY738Evidence from: Notonecta glauca, a Eurasian species
- Declared limitMissouri lists fish among the animals that prey on backswimmers, but no source consulted rates them as important forage. The Florida extension account also records them eating fish eggs and fry.MDC-BACKSWIMMERS, UF-BACKSWIMMER-EENY738, UWM-BOATMEN-BACKSWIMMERS
- Declared limitNo source consulted describes whether they row with alternating or simultaneous strokes.record’s sources
- Size bandadult: 10-29 (usually under 13) mmMDC-BACKSWIMMERS, PURDUE-HEMIPTERA, UF-BACKSWIMMER-EENY738, WVDEP-INVERT-GUIDE
- Water typelake-marginrecord’s sources
- Water typereservoirrecord’s sources
- Water typestreamrecord’s sources
- Water typeriverrecord’s sources
- Water typespringrecord’s sources
- Life stagenymphrecord’s sources
- Life stageadultrecord’s sources
- Where it sitsponds and quiet corners of lakes and streams, clinging to submerged vegetationMDC-BACKSWIMMERS, WVDEP-INVERT-GUIDE
- Where it sitsa backswimmer rests tilted head-down at the surface with the tip of its abdomen through the filmMDC-BACKSWIMMERS
- How it movesrows with long oar-like hind legs, belly upwardsMDC-BACKSWIMMERS
- How it movesrests tilted head-down at the surface with the tip of the abdomen through the filmMDC-BACKSWIMMERS
- How it moveswaits in ambush, holding on to submerged vegetationMDC-BACKSWIMMERSEvidence from: Missouri
- Sources disagreeHow badly a backswimmer bites differs by source: painful if mishandled in one state field guide, very rare and often the result of rough handling in a university extension account. Both agree it takes handling.record’s sources
- Sources disagreeMissouri gives adult backswimmers as usually under half an inch and Purdue lists one at half an inch; WVDEP puts the family in its 15–29 mm class, and a Florida profile of a Eurasian species gives about 16 mm.record’s sources
- Missouri Department of ConservationMDC-BACKSWIMMERS · State · read 2026-09-04
- University of Florida IFAS ExtensionUF-BACKSWIMMER-EENY738 · University · read 2026-09-04
- West Virginia Department of Environmental ProtectionWVDEP-INVERT-GUIDE · State · read 2026-09-04
- Purdue University ExtensionPURDUE-HEMIPTERA · University · read 2026-09-04
- Missouri Department of ConservationMDC-DIVING-BEETLES · State · read 2026-09-04
- U.S. Environmental Protection AgencyEPA-MACRO-TIPSHEET · National · read 2026-09-04
- University of Wisconsin–Milwaukee Field StationUWM-BOATMEN-BACKSWIMMERS · University · read 2026-09-25
- Missouri Department of ConservationMDC-WATER-BOATMEN · State · read 2026-09-04
The pages themselves
All 224, and what each one is holding up.
- Missouri Department of Conservation
MDC-BACKSWIMMERS
- Missouri Department of Conservation
MDC-DIVING-BEETLES
- Missouri Department of Conservation
MDC-WATER-BOATMEN
- Purdue University Extension
PURDUE-HEMIPTERA
- U.S. Environmental Protection Agency
EPA-MACRO-TIPSHEET
- University of Florida IFAS Extension
UF-BACKSWIMMER-EENY738
- University of Wisconsin–Milwaukee Field Station
UWM-BOATMEN-BACKSWIMMERS
- West Virginia Department of Environmental Protection
WVDEP-INVERT-GUIDE
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