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What the sources say

Giant Freshwater StingrayUrogymnus polylepis

Every figure, record and mechanism on the Giant Freshwater Stingray profile was written from a source, and this is the working table behind it: 40 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.

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Source
01

Campbell et al. 2023

Campbell et al. (2023). A Review of the Conservation Status and Ecology of the Giant Freshwater Whipray (Urogymnus polylepis) across Its Known Distribution.

The page saysThe 300-kilogram Mekong river phantom with a barbed tail spine and the record for the largest freshwater fish ever caught and officially recorded.
The source saysas of June 2022, a specimen from Cambodia became the largest freshwater fish ever caught and officially recorded ... a weight of 300 kg (Figure 1a) [2]. ... Near the base of the tail is a long, barbed spine [1]Note: 'Mekong river phantom' is a flourish
The page saysA World-Record Weighed on the Mekong
The source saysa specimen from Cambodia became the largest freshwater fish ever caught and officially recorded
The page saysIn June 2022, a female giant freshwater stingray (Urogymnus polylepis) was caught in the Mekong River in Stung Treng, Cambodia, with a disc width of 220 centimeters (7.2 feet), a total length of 398 centimeters (13 feet), and a weight of 300 kilograms (661 pounds)
The source saysFemale caught in the Mekong River in Stung Treng, Cambodia, on 14 June 2022. Measurements: 220 cm disc width (DW), 220 cm disc length (DL), 398 cm total length (TL), 300 kg.Note: 220 cm = 7.2 ft, 398 cm = 13 ft, 300 kg = 661 lb
The page saysA 2023 review of the species calls her the largest freshwater fish ever caught and officially recorded
The source saysas of June 2022, a specimen from Cambodia became the largest freshwater fish ever caught and officially recordedNote: the review is Campbell et al. 2023 itself; the Figure 1a caption identifies the record holder as the Stung Treng female
The page saysFishers from the Chao Phraya and Mekong basins have reported rays as large as 500 to 600 kilograms, but the largest one reliably measured, weighed, and documented is the Stung Treng female
The source saysThe largest individual to be reliably measured, weighed, and documented has a disc width of 220 cm, a total length of 398 cm, and a weight of 300 kg (Figure 1a) [2]. Fishers from the Chao Phraya and Mekong basins reported individuals reaching even greater sizes, as large as 500–600 kg [1].Note: Figure 1a is the Stung Treng female (see the claim above)
The page saysThe species is thought to reach a maximum age of 12 or more years and to mature at around three years old and 110 centimeters across the disc, with a generation length of 8 to 22 years
The source saysthe giant freshwater whipray is thought to reach a maximum age of 12 or more years, have a generation length of 8–22 years, and mature at approximately three years and 110 cm disc width [9]Note: cites [9], the IUCN assessment; the 'thought to' hedge covers all three figures
The page saysIn India, the gut contents of ten individuals showed a preference for bony fish, shrimp, and crabs
The source saysSen et al. [7] investigated 13 giant freshwater whiprays landed in Odisha and West Bengal between 2018 and 2021 ... Gut content analysis of ten individuals showed a preference for bony fishes, shrimps, and crabs [7].
The page saysIt's known from ten countries and several major river basins across eastern India and Southeast Asia, including the Ganges, the Mekong, and the Chao Phraya
The source saysThe giant freshwater whipray is patchily distributed across eastern India and Southeast Asia [5]. ... The giant freshwater whipray is known in ten countries and several major river basins, including the Mekong, Chao Phraya, and Ganges [9].
The page saysestuaries across ten countries in eastern India and Southeast Asia, including the Mekong, Chao Phraya, and Ganges basins
The source saysThe species has been documented from inland rivers, estuaries, and coastal marine habitats [9]. ... The giant freshwater whipray is patchily distributed across eastern India and Southeast Asia [5]. ... The giant freshwater whipray is known in ten countries and several major river basins, including the Mekong, Chao Phraya, and Ganges [9].
The page says2.2-meter disc width, a 300-kilogram record catch, and a long, barbed tail spine
The source saysThe largest individual to be reliably measured, weighed, and documented has a disc width of 220 cm, a total length of 398 cm, and a weight of 300 kg (Figure 1a) [2]. ... Near the base of the tail is a long, barbed spine [1]Note: 220 cm = 2.2 m
The page saysSome fishers track it in the sand.
The source sayssome fishers target the species when they notice the whipray's tracks in the sand on sandbars
The page saysA 2021 survey in Khong District, Laos, found that some fishers target the ray when they spot its tracks in the sand on sandbars, or see one coming to shore to eat earthworms early in the rainy season
The source says2.5. Lao PDR ... a survey of fishers in Khong District in 2021 revealed that some fishers target the species when they notice the whipray's tracks in the sand on sandbars or individuals coming to shore to eat earthworms in the early rainy season.
The page saysGiving Birth When Caught
The source saysbecause of capture-induced parturition
The page saysFemales give birth to live pups, with one to three considered a typical litter, and each pup is about 30 centimeters across the disc at birth
The source saysA viviparous species, females give birth to live pups, with litter sizes of 1–3 pups considered typical. Pups are approximately 30 cm in disc width at birth [9].
The page saysOf 13 rays landed in Odisha and West Bengal, India, between 2018 and 2021, three pregnant females carried four to 15 developed embryos, considerably more than the litter size previously thought typical
The source saysSen et al. [7] investigated 13 giant freshwater whiprays landed in Odisha and West Bengal between 2018 and 2021 ... three of the females were pregnant with pups. Pregnant females had a range of four to 15 developed embryos, which is considerably higher than what was previously thought to be the typical litter size for this species (1–2 pups) [9].
The page saysBeing caught can make a pregnant female give birth, a phenomenon called capture-induced parturition that has been documented several times in this species
The source saysbecause of capture-induced parturition, the population-level impact from fishing is likely higher than would be expected from the number of catches alone. This phenomenon has been documented multiple times for giant freshwater whipray [1,59].Note: the first clause glosses the term capture-induced parturition (birth brought on by capture)
The page saysBecause of it, the population-level impact of fishing is likely higher than the number of catches alone would suggest
The source saysAdams et al. [59] noted that, because of capture-induced parturition, the population-level impact from fishing is likely higher than would be expected from the number of catches alone.
The page saysA Barbed Spine and a Falling Population
The source saysNear the base of the tail is a long, barbed spine [1] that can inflict painful wounds.Note: Heading; the falling population is the section's Red List claim ("population declines as high as 79%").
The page saysNear the base of its long, whiplike tail sits a long, barbed spine that can inflict painful wounds
The source saysa broad, nearly circular body shape with a long, thin, whiplike tail [5]. Near the base of the tail is a long, barbed spine [1] that can inflict painful wounds.
The page saysbecause of population declines as high as 79 percent over the last century
The source saysThe International Union for Conservation of Nature (IUCN) has assessed the giant freshwater whipray as endangered due to population declines as high as 79% over the last century [9].Note: 'because of' renders the source's 'due to'
The page saysKey threats include high fishing pressure, bottom trawls, pollution, habitat degradation, and dams
The source saysKey threats to giant freshwater whipray across its range were identified as high fishing pressure, unmanaged artisanal fisheries, lack of legal protection, habitat degradation, pollution, dams, and bottom trawls, among others
The page saysThe aquarium trade is a threat too: the species does not survive well in aquariums, so the trade requires a continual harvest from the wild
The source saysThe aquarium trade has also been identified as a threat to this species, especially because it does not survive well in aquaria and thus requires continual harvest from the wild [9].Note: 'so' renders the source's 'thus'
The page saysNo. Until the early 2000s, scientists thought its range reached northern Australia and New Guinea, but molecular and body-shape work showed that the rays living there were a separate species, the freshwater whipray (Urogymnus dalyensis)
The source saysUntil the early 2000s, its range was thought to include northern Australia and New Guinea, but molecular and morphometric work by Last and Manjaji-Matsumoto [3] showed that individuals in this region were a separate species, the freshwater whipray Urogymnus dalyensis.
The page saysweightKg: 200
The source saysweights ranging from 95–300 kgNote: task #799; midpoint, rounded, of the 13 mature rays landed in India 2018-2021, the only adult weight sample on record. Heavy class (100 to 1000 kg) where the name guess gave Medium. Not in a curated matchup

Source
02

Animal Diversity Web, University of Michigan

Himantura chaophraya (freshwater whipray). Animal Diversity Web, University of Michigan.

The page saysThe Riverbed Buffet
The source saysGiant freshwater stingrays generally feed on river bottoms.
The page saysThe giant freshwater stingray generally feeds on river bottoms, mainly on fish and invertebrates such as mollusks
The source saysGiant freshwater stingrays generally feed on river bottoms. ... Their diet consists mainly of benthic fishes and invertebrates. ... Animal Foods fish mollusks
The page saysIts two jaws act like crushing plates, with small teeth that keep chewing the food
The source saysTheir mouth contains two jaws that act like crushing plates, and small teeth to continue chewing up food.
The page saysMainly bottom-dwelling fish and invertebrates, including mollusks, shrimp, and crabs
The source saysTheir diet consists mainly of benthic fishes and invertebrates. ... Animal Foods fish mollusks aquatic or marine worms aquatic crustaceansNote: shrimp and crabs are crustaceans; Campbell's gut-content study names them (claim above)
The page saysit's typically found over sandy bottoms 5 to 20 meters down in large rivers
The source saysThis species is typically found over sandy bottoms in large rivers, at depths of 5 to 20 meters.
The page saysSandy river bottoms
The source saysThis species is typically found over sandy bottoms in large rivers
The page saysAnimal Diversity Web adds that the spine is serrated and has a venom gland
The source saysthe ventral side has a spine with saw-like serrations and an associated venom gland
The page saysAnimal Diversity Web reports no unprovoked attacks
The source saysThere have been no reports of unprovoked attacks.
The page saysThe ray can use its venomous tail spine in self-defense, and when fishers try to catch one, it whips that tail to get away
The source saysThis species also has a strong, serrated, venomous spine on its tail, which can be used in self defense. ... When fishermen try to catch giant freshwater stingrays, they will whip their tail (bearing its large, serrated, venomous spine) to try and get away.
The page saysThe same source says the spines have been reported to be strong enough to go through wooden boats
The source saysThese spines have been reported to be strong enough to go through wooden boats.
The page saysIts dark back keeps predators swimming above from seeing it against the sand, while its pale belly hides its outline from predators below against the incoming sunlight
The source saysThe dorsum is darkly colored, preventing predators swimming above them from seeing them against the sand, while the lighter colored belly obscures an individuals body outline from predators below, due to incoming sunlight.
The page saysAnimal Diversity Web says this countershading and a sedentary lifestyle let even small rays blend in with the river bottom
The source saysTheir countershaded color pattern and sedentary lifestyle offer even small individuals protection from larger predators, as they are able to blend in with the river bottom.
The page saysBy blending in.
The source saysthey are able to blend in with the river bottom
The page saysdangerLevel: High
The source saysWhen fishermen try to catch giant freshwater stingrays, they will whip their tail (bearing its large, serrated, venomous spine) to try and get away.Note: task #799; ADW also: "There have been no reports of unprovoked attacks." Dangerous when provoked, not on contact.
The page saysa ray whose countershading and sedentary life let it vanish against the river bottom
The source saysTheir countershaded color pattern and sedentary lifestyle offer even small individuals protection from larger predators, as they are able to blend in with the river bottom.Note: task #799, vibe.reason

Source
03

Grant et al. 2021

Grant et al. (2021). Urogymnus polylepis. The IUCN Red List of Threatened Species 2021: e.T195320A104294071.

The page saysThe species is Endangered on the IUCN Red List, assessed in 2021
The source saysIUCN Red List category: Endangered (EN). Urogymnus polylepis (Bleeker, 1852), IUCN taxon 195320.Note: the category comes from GBIF's copy of the assessment; the 2021 date is the assessment's own year, in its DOI (iucn.uk.2021-2) and its title

How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.