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What the sources say

Emperor DragonflyAnax imperator

Every figure, record and mechanism on the Emperor Dragonfly profile was written from a source, and this is the working table behind it: 47 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

Vinko et al. 2024

Vinko et al. (2024). Anax imperator. The IUCN Red List of Threatened Species 2024: e.T59812A208815239.

The page saysThe IUCN Red List rates it Least Concern
The source saysIUCN Red List category: Least Concern (LC).Note: stats.conservationStatus

Source
02

Quenta Herrera et al. 2018

Quenta Herrera et al. (2018). Temperature effects on ballistic prey capture by a dragonfly larva. Ecology and Evolution.

The page saysA big dragonfly whose larva fires a hooked mouthpart at prey, too fast for a water flea to escape
The source saysprey did not have the opportunity to move and/or escape due to the high velocity of the predator during the attackNote: tagline
The page saysA larva with a labial mask, a hooked mouthpart that shoots out at prey
The source saysDragonfly larvae capture their prey by extending at a high velocity their labial mask which has movable hooksNote: stats.superpower
The page saysDragonfly larvae catch prey by shooting out a labial mask, a mouthpart with movable hooks
The source saysDragonfly larvae capture their prey by extending at a high velocity their labial mask which has movable hooks
The page saysScientists call this kind of strike ballistic, like the tongue of a chameleon or a frog
The source saysThis type of attack is called ballistic and is similar to tongue projection in chameleons and frogs.
The page saysemperor larvae struck at 0.03 to 0.25 metres per second
The source saysA. imperator is more than 10 times faster than Daphnia , with striking velocities ranging from 0.03 to 0.25 m/s
The page saysmore than 10 times faster than the water fleas they hunted could swim
The source saysA. imperator is more than 10 times faster than Daphnia
The page saysThe prey had no time to escape
The source saysprey did not have the opportunity to move and/or escape due to the high velocity of the predator during the attack
The page saysabout 40% of mistakes fell short of the target and about 60% aimed above or below it
The source sayssome 40% of mistakes were undershooting and some 60% aimed below or above the target
The page saysAn earlier study of Anax larvae, the emperor's genus, timed the mask at 25 to 40 milliseconds to extend fully
The source saysthe time needed for Anax larvae to fully extend their labial mask (range 25–40 ms
The page saysWhether it caught them depended mainly on aim
The source saysthe capture success mainly depended on the accuracy of the predator in capturing the prey
The page saysAn Anax larva's labial mask shoots out in 25 to 40 milliseconds
The source saysthe time needed for Anax larvae to fully extend their labial mask (range 25–40 msNote: vibe.reason animal clause, same source as the body claim "An earlier study of Anax larvae, the emperor's genus, timed "
The page saysin lab tests the water fleas it struck had no time to escape
The source saysprey did not have the opportunity to move and/or escape due to the high velocity of the predator during the attackNote: vibe.reason animal clause, same source as the body claim "The prey had no time to escape"

Source
03

Minot, Le Gall & Huste 2019

Minot, Le Gall & Huste (2019). Biometry of the large dragonfly Anax imperator (Odonata: Aeshnidae): A study of traits from larval development to adults. European Journal of Entomology.

The page saysIn a study in Normandy, France, mature females averaged 1.26 g and mature males 0.97 g
The source saysmature females (1.26 ± 0.09 g) were signi fi cantly heavier than mature males (0.97 ± 0.07 g
The page saysBig, but about a gram
The source saysmature females (1.26 ± 0.09 g) were signi fi cantly heavier than mature males (0.97 ± 0.07 gNote: heading

Source
04

Sharkey, Partridge & Roberts 2015

Sharkey, Partridge & Roberts (2015). Polarization sensitivity as a visual contrast enhancer in the Emperor dragonfly larva, Anax imperator (Leach, 1815). Journal of Experimental Biology.

The page saysIn fresh water, light is often partly polarized, meaning its waves vibrate mostly in one direction
The source sayspartially polarized lighting conditions that occur naturally in freshwater environmentsNote: faq
The page saysIn lab tests the larvae tracked a moving striped pattern better through such light, as if the pattern's contrast had been raised by 8%
The source saysAnimals were shown to track the movement of a square-wave grating more closely when it was viewed through the horizontally polarized light field, equivalent to a similar increase in tracking ability observed in response to an 8% increase in the intensity contrast of the stimuli.Note: faq

Source
05

Herzog et al. 2016

Herzog et al. (2016). The complete mitochondrial genome of the emperor dragonfly Anax imperator LEACH, 1815 (Odonata : Aeshnidae) via NGS sequencing. Mitochondrial DNA Part B.

The page saysThe emperor is widespread across the Old World, in all types of standing and slow-running fresh water
The source saysis a widespread and common species in the old world inhabiting all types of standing- and slow-running freshwater ecosystems
The page saysIt was one of the first dragonflies whose recent shift northward was noticed and put down to climate change
The source saysIt was one of the first odonate species for which a recent range shift northwards (e.g. Parr 2010 ) and towards higher altitudes (Westermann 2003 ; Hunger et al. 2006 ) was noticed due to global climate changeNote: faq
The page saysIt was first recorded in Sweden in 2002
The source saysThe first records of this species in Sweden were 2002Note: faq
The page saysit crossed 970 km northward through Scandinavia in only 11 years
The source saysIn only 11 years A. imperator crossed a distance of 970 km northwards through ScandinaviaNote: faq

Source
06

Josten, Gorb & Büsse 2022

Josten, Gorb & Büsse (2022). The mouthparts of the adult dragonfly Anax imperator (Insecta: Odonata), functional morphology and feeding kinematics. Journal of Morphology.

The page saysAdults have biting-chewing mouthparts
The source saysLike all adult dragonflies, A. imperator possesses carnivorous-type of biting-chewing mouthparts.

Source
07

British Dragonfly Society

Emperor Dragonfly. British Dragonfly Society.

The page saysan adult is about 78 mm long
The source saysAdult Identification Length: 78mm
The page saysBritain's bulkiest dragonfly
The source saysBritain’s bulkiest Dragonfly.
The page saysThe larva reaches 45 to 56 mm
The source saysEmperors have the largest larvae: 45-56mm
The page saysEmperors rarely settle, even eating prey in flight
The source saysIt rarely settles, even eating its prey in flight.
The page saysThe female lays her eggs alone, in floating pondweed
The source saysThe female lays her eggs, alone, in floating pondweed.
The page saysIn Britain it lives in Wales and most of England, and it has been recorded in Scotland since 2003
The source saysFound across Wales, most of England; its distribution has greatly increased since the 1990s. The species has been recorded in Scotland since 2003
The page saysBoth have an apple-green thorax and a dark line down the abdomen
The source saysApple-green thorax. Green or blue eyes. Central dark line down the abdomen.Note: faq
The page saysThe male's abdomen is blue and the female's is usually green, though hers is occasionally blue
The source saysMale: Blue abdomen. Female: Green abdomen. Occasionally blue.Note: faq

Source
08

Duncan

Duncan. Species of the day: Emperor Dragonfly. Sussex Wildlife Trust.

The page saysFlying insects, large butterflies and other dragonflies
The source saysa taste for large butterflies and even other dragonfliesNote: stats.diet
The page sayslarvae take tadpoles and small fish
The source sayswill gorge on anything smaller than themselves, including tadpoles and small fishNote: stats.diet
The page saysit will gorge on anything smaller than itself, tadpoles and small fish included
The source sayswill gorge on anything smaller than themselves, including tadpoles and small fish
The page saysAn adult may live for a couple of months or more
The source saysan adult Emperor may live for a couple of months or more
The page saysthe Sussex Wildlife Trust says it spends around ten times longer underwater as a larva
The source saysit'll spend around ten times longer living underwater as an aggressive predatory larvae
The page saysMale emperors are very territorial
The source saysThe male Emperor has a supremely territorial nature.
The page saysdescribes them clashing with other dragonflies in the air
The source sayshe’ll viciously clash with other Dragonflies in bouts of aerial supremacy
The page saysTheir menu includes large butterflies and other dragonflies
The source saysa taste for large butterflies and even other dragonflies

Source
09

First Nature

Anax imperator - Emperor dragonfly. First Nature.

The page saysMainly large, weedy ponds, lakes, canals and slow streams across most of Europe, eastern Asia and much of Africa
The source saysMainly seen over large, densely-vegetated ponds, flooded gravel pits, shallow lakes, canals, large ditches and slow-flowing streamsNote: stats.habitat
The page saysMainly large, weedy ponds, lakes, canals and slow streams across most of Europe, eastern Asia and much of Africa
The source saysOn the mainland the Emperor Dragonfly is found throughout most of Europe and eastern Asia; it is also a common sight in much of Africa.Note: stats.habitat
The page saysThe emperor dragonfly, Anax imperator, starts life underwater
The source saysthe juvenile insects spend either one or two years as larvae, eventually emerging as winged adults during the night
The page saysa wingspan of about 10.5 cm
The source saysa wingspan of about 10.5cm
The page saysThey patrol the water's edge and chase off intruders
The source saysThe males are territorial and patrol the water margins, chasing off intruders.
The page saysIt is found throughout most of Europe and eastern Asia and is common in much of Africa
The source saysOn the mainland the Emperor Dragonfly is found throughout most of Europe and eastern Asia; it is also a common sight in much of Africa.
The page saysOne or two years
The source saysthe juvenile insects spend either one or two years as larvaeNote: faq
The page saysIts eggs hatch after about three weeks
The source saysThe eggs hatch after about three weeksNote: faq
The page saysit emerges, during the night, as a winged adult
The source sayseventually emerging as winged adults during the nightNote: faq

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.