Epaulet Skimmer (Orthetrum chrysostigma)

The photo above (by Gert Bensch) can be viewed in OdonataMAP here.

Orthetrum chrysostigma, commonly known as Epaulet Skimmer is a dragonfly in the family Libellulidae.

Identification

Medium sized

Length up to 46mm; Wingspan reaches 69mm.

Both sexes are among the more easily recognised Orthetrum species, due to the single diagonal stripe on the sides of the thorax.

Fully pruinose males, however, are hard to identify and are best told by the distinctive shape of the secondary genitalia.

Most similar to the closely related Two-striped Skimmer (Orthetrum caffrum), but that species has a darker, browner thorax with two, pale diagonal stripes on the sides.

Orthetrum chrysostigma – Male
Ndumo Game Reserve, KwaZulu-Natal
Photo by Ryan Tippett
Orthetrum chrysostigma – Female
False Bay, iSimangaliso Wetland Park, KwaZulu-Natal
Photo by Ryan Tippett

Habitat

Makes use of a wide range of freshwater habitats, including Rivers, streams, lakes, pans, dams and water-holes. Favours sites that are fairly open with exposed rocks, sand or gravel. Most common along rivers in the savanna regions.

Habitat – Orange River near Keimoes, Northern Cape
Photo by Ryan Tippett

Behaviour

Often perches on the ground, but also on rocks and exposed stems and twigs. Hunts from a perch with a rapid, darting flight. Frequently returns to the same perch. Both sexes can be found in the same area.

Status and Conservation

Common and widespread. Listed as of Least Concern in the IUCN Red List of Threatened Species. The Epaulet Skimmer is fairly resistant towards habitat damage and is often common at man-made and degraded sites.

Distribution

Very widespread and occurs virtually throughout Africa, including North Africa. It also occurs in parts of Southern Europe and the Middle East. In South Africa it occurs virtually throughout, but is scarce in the dry central regions.

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

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.

Dragonfly Atlas: Megan Loftie-Eaton, Sally Hofmeyr, Ryan Tippett & Les Underhill
Dragonfly Atlas: Megan Loftie-Eaton, Sally Hofmeyr, Ryan Tippett & Les Underhill
Megan Loftie-Eaton is our communications, social media and citizen science coordinator. Prior to her work for the BDI, she coordinated OdonataMAP, the Atlas of African Odonata. Sally Hofmeyr has many years' experience in the academic world, writing her own material and editing the work of others. Her academic background is in the natural sciences: her PhD and first postdoc in ornithology and environmental change (Animal Demography Unit, University of Cape Town). Ryan Tippett is an enthusiastic contributor to Citizen Science and has added many important and interesting records of fauna and flora. He has been a member of the VMU since 2014 and has currently submitted over 11000 records. He is also on the expert identification panel for the Odonata Map project. Prof Les Underhill has been Director of the Animal Demography Unit (ADU) at the University of Cape Town since it started in 1991. Although citizen science in biology is Les’s passion, his academic background is in mathematical statistics.