Sussex Dragonfly Group

Red-eyed Damselfly
Erythromma najas (Hansemann, 1823)
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Suborder: Zygoptera
Family: Coenagrionidae

Red-eyed Damselfly
Erythromma najas

Suborder: Zygoptera
Family: Coenagrionidae

The blue ‘tail’ to a greenish-black abdomen and unmistakable bright, blood-red eyes single out the males. Females are less red-eyed than males and lack the blue-tipped abdomen. The species is characteristically found on lily pads in the middle of a pond or lake - so using binoculars is a great help.

Erythromma najas
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Male
Photo: David Sadler
Erythromma najas
2 / 5
Male
Photo: David Sadler
Erythromma najas
3 / 5
Female
Photo: David Sadler
Erythromma najas
4 / 5
Pair in tandem
Photo: David Sadler
Erythromma najas
5 / 5
Descending to oviposit
Photo: David Sadler

More images

National status
Locally common in south-eastern England and the Welsh Borders. Of late, there has been an expansion in range to the west and north.

Status in Sussex
Locally common across the county with a concentration on the Pevensey Levels; an apparent reduction there may represent changes in observer coverage. Fairly well distributed across the Low Weald, but more patchy in the High Weald and Wealden Greensand. Scarce on the coastal strip.

Distribution at 1km scale

Erythromma najas distribution (all)
Erythromma najas distribution pre 1980
Erythromma najas distribution 1980 - 1989
Erythromma najas distribution 1990 - 1999
Erythromma najas distribution 2000 - 2009
Erythromma najas distribution 2010 - 2019
Erythromma najas distribution 2010 on

Historical records
This is one of several species first recorded in Sussex on 29 August 1908 at a site near Tunbridge Wells by E. Speyer (Bloomfield 1910). Dannreuther (1939) described it as “Fairly rare even where it breeds”. It was not until the 1940s that this species was regularly recorded by N. Moore (Chelmick 1979). There seems to have been a recent increase, possibly due to migration, being recorded for the first time at Castle Water in 1997 (Rye Harbour Report 1999), and at Icklesham in August 2002 (after the influx of Small Red-eyed had been noted; Hunter 2003).

Flight times
Early May - early September. There is evidence that the flight period may be extending at both ends of the season.

Phenology (adult)

Erythromma najas phenology (all)
Erythromma najas phenology pre 1980
Erythromma najas phenology 1980 - 1989
Erythromma najas phenology 1990 - 1999
Erythromma najas phenology 2000 - 2009
Erythromma najas phenology 2010 - 2019
Erythromma najas phenology 2010 on
Erythromma najas habitat
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Red eyed Damselfly habitat at Sheffield Park
Photo: Simon Linington

Habitat
Lakes and large ponds with plenty of floating vegetation such as water lilies; also on quiet stretches of rivers and canals.

Conservation
On still-water bodies, it is important to maintain large areas of floating vegetation, such as water lilies and pondweeds (Potamogeton spp.), that are used by territorial males, and marginal vegetation favoured by females and mating pairs. Meandering watercourses with slacks and other calm stretches that can be colonised by floating vegetation are ideal habitats. These can be destroyed by engineering activities (such as canalisation) designed to increase water flow. The restoration of the Shopham Loop on the western Rother will help this species.

Erythromma najas similar species
1 / 1
Photos: David Sadler & Simon Linington

Similar species
The male of this species has red eyes and so should only be confused with the Small Red-eyed Damselfly. It has slightly longer wings and duller red eyes but the key feature to look for is the blue pattern on the tip of the abdomen. The sides of abdominal segment 8 are black in this species but blue in Small Red-eyed Damselfly. The female has short, incomplete antehumeral stripes over the thorax whereas in Small Red-eyed Damselfly these are complete (see photographic comparison). For other potential confusion damselfly species see under Azure Damselfly (including photographic comparisons).

The blue ‘tail’ to a greenish-black abdomen and unmistakable bright, blood-red eyes single out the males. Females are less red-eyed than males and lack the blue-tipped abdomen. The species is characteristically found on lily pads in the middle of a pond or lake - so using binoculars is a great help.

Erythromma najas
1 / 5
Male
Photo: David Sadler
Erythromma najas
2 / 5
Male
Photo: David Sadler
Erythromma najas
3 / 5
Female
Photo: David Sadler
Erythromma najas
4 / 5
Pair in tandem
Photo: David Sadler
Erythromma najas
5 / 5
Descending to oviposit
Photo: David Sadler

National status
Locally common in south-eastern England and the Welsh Borders. Of late, there has been an expansion in range to the west and north.

Status in Sussex
Locally common across the county with a concentration on the Pevensey Levels; an apparent reduction there may represent changes in observer coverage. Fairly well distributed across the Low Weald, but more patchy in the High Weald and Wealden Greensand. Scarce on the coastal strip.

Distribution at 1km scale

Erythromma najas distribution (all)
Erythromma najas distribution bre 1980
Erythromma najas distribution 1980 - 1989
Erythromma najas distribution 1990 - 1999
Erythromma najas distribution 2000 - 2009
Erythromma najas distribution 2010 - 2019
Erythromma najas distribution 2020 on

Historical records
This is one of several species first recorded in Sussex on 29 August 1908 at a site near Tunbridge Wells by E. Speyer (Bloomfield 1910). Dannreuther (1939) described it as “Fairly rare even where it breeds”. It was not until the 1940s that this species was regularly recorded by N. Moore (Chelmick 1979). There seems to have been a recent increase, possibly due to migration, being recorded for the first time at Castle Water in 1997 (Rye Harbour Report 1999), and at Icklesham in August 2002 (after the influx of Small Red-eyed had been noted; Hunter 2003).

Flight times
Early May - early September. There is evidence that the flight period may be extending at both ends of the season.

Phenology (adult)

Erythromma najas phenology (all)
Erythromma najas phenology pre 1980
Erythromma najas phenology 1980 - 1989
Erythromma najas phenology 1990 - 1999
Erythromma najas phenology 2000 - 2009
Erythromma najas phenology 2010 - 2019
Erythromma najas phenology 2020 on
Erythromma najas habitat
1 / 1
Red eyed Damselfly habitat at Sheffield Park
Photo: Simon Linington

Habitat
Lakes and large ponds with plenty of floating vegetation such as water lilies; also on quiet stretches of rivers and canals.

Conservation
On still-water bodies, it is important to maintain large areas of floating vegetation, such as water lilies and pondweeds (Potamogeton spp.), that are used by territorial males, and marginal vegetation favoured by females and mating pairs. Meandering watercourses with slacks and other calm stretches that can be colonised by floating vegetation are ideal habitats. These can be destroyed by engineering activities (such as canalisation) designed to increase water flow. The restoration of the Shopham Loop on the western Rother will help this species.

Erythromma najas similar species
1 / 1
Photos: David Sadler & Simon Linington

Similar species
The male of this species has red eyes and so should only be confused with the Small Red-eyed Damselfly. It has slightly longer wings and duller red eyes but the key feature to look for is the blue pattern on the tip of the abdomen. The sides of abdominal segment 8 are black in this species but blue in Small Red-eyed Damselfly. The female has short, incomplete antehumeral stripes over the thorax whereas in Small Red-eyed Damselfly these are complete (see photographic comparison). For other potential confusion damselfly species see under Azure Damselfly (including photographic comparisons).