Long Skimmer (Orthetrum trinacria)

Cover photo by Diana Russell.

Find this species in the FBIS database (Freshwater Biodiversity Information System) here.

Family Libellulidae

Identification

Large size

Length up to 67mm; Wingspan attains 82mm.

The male Long Skimmer is unlikely to be mistaken for another species. The combination of its size, distinctive shape and dark greyish-blue colour render it unmistakable.

Females are also readily identifiable and they have the same distinct shape of the males but are overall pale yellow, boldly marked with black. Females and immature males can resemble those of Orthetrum icteromelas (Spectacled Skimmer) in terms of colouration and patterning. The Spectacled Skimmer is significantly smaller, and there is no size overlap between the two species. The Long Skimmer is similar in size to the Robust Skimmer (Orthetrum robustum), but the two are easily separated on colouration

Click here for more details on identification.

Habitat

The Long Skimmer is most often found around the fringes of still, open water habitats like lakes, pools and dams. It is less regular at the margins of rivers and streams, where it favours slower moving sections. The Long Skimmer occurs over a range of habitats throughout South Africa, including the arid and semi-arid regions. Long Skimmers also make use of seasonal wetlands as well as artificial reservoirs and livestock drinking sites in the arid interior.

Behaviour

The Long Skimmer is most often seen perched on vegetation over or near the waters edge. It also regularly sits on bare sand, gravel or rocks. This species hunts from a perch and the flight is swift and typically low over the water. The Long Skimmer is a voracious predator that regularly feeds on large insects like butterflies and other dragonflies.

Orthetrum trinacria is on the wing from October to May, although it is most common in late summer.

Status and Conservation

The Long Skimmer is common over large areas of southern Africa. It is listed as of Least Concern in the IUCN Red List of Threatened Species.

Distribution

The Long Skimmer is a very widespread species, occurring throughout Africa and parts of Southern Europe and the Middle East. Orthetrum trinacria occurs all over South Africa, but it is less numerous in the drier central regions.

Below is a map showing the distribution of records for Long Skimmer in the OdonataMAP database as at February 2020.

Below is a map showing the distribution of records for Long Skimmer in the OdonataMAP database as of December 2024.

The next map below is an imputed map, produced by an interpolation algorithm, which attempts to generate a full distribution map from the partial information in the map above. This map will be improved by the submission of records to the OdonataMAP section of the Virtual Museum.

Ultimately, we will produce a series of maps for all the odonata species in the region. The current algorithm is a new algorithm. The objective is mainly to produce “smoothed” maps that could go into a field guide for odonata. This basic version of the algorithm (as mapped above) does not make use of “explanatory variables” (e.g. altitude, terrain roughness, presence of freshwater — we will be producing maps that take these variables into account soon). Currently, it only makes use of the OdonataMAP records for the species being mapped, as well as all the other records of all other species. The basic maps are “optimistic” and will generally show ranges to be larger than what they probably are.

These maps use the data in the OdonataMAP section of the Virtual Museum, and also the database assembled by the previous JRS funded project, which was led by Professor Michael Samways and Dr KD Dijkstra.

Further Resources

The use of photographs by Diana Russell is acknowledged. All other photographs by Ryan Tippett.

Long Skimmer Orthetrum trinacria (Selys, 1841)

Other common names: Gestrekte Skepper (Afrikaans)

Recommended citation format: Loftie-Eaton M; Navarro R; Tippett RM; Underhill L. 2025. Long Skimmer Orthetrum trinacria. Biodiversity and Development Institute. Available online at https://thebdi.org/2020/05/13/long-skimmer-orthetrum-trinacria/

References: Tarboton, M; Tarboton, W. (2019). A Guide to the Dragonflies & Damselflies of South Africa. Struik Nature.

Samways, MJ. (2008). Dragonflies and Damselflies of South Africa. Pensoft

Samways, MJ. (2016). Manual of Freshwater Assessment for South Africa: Dragonfly Biotic Index.Suricata 2. South African National Biodiversity Institute, Pretoria

Martens, A; Suhling, F. (2007). Dragonflies and Damselflies of Namibia. Gamsberg Macmillan.

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