Guinea Skimmer (Orthetrum guineense)

The photo above (by Rob Dickinson) can be viewed in OdonataMAP here.

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

Family Libellulidae

Orthetrum guineenseGUINEA SKIMMER

Identification

Medium Sized

Length up to 44mm; Wingspan attains 71mm.

Most similar to Orthetrum machadoi (Highland Skimmer). The two species were up until recently thought to be conspecific. Mature males of the two can only be definitively identified by the respective shapes of the secondary genitalia.

Immature males and females of Orthetrum guineense can be recognised by the mostly unmarked thorax sides, the fine black markings on the abdomen and by the fine black line along the base of the thorax (diagnostic).

Click here for more details on identification.

Orthetrum guineense – Mature male
Near Tshipise, Limpopo
Photo by John Wilkinson
Orthetrum guineense – Female
Mphaphuli Nature Reserve, Limpopo
Photo by John Wilkinson

Habitat

Inhabits the marshy fringes of flowing streams and rivers. Usually in hilly savanna regions above 700m a.s.l.

Behaviour

Usually found close to the water where it perches on rocks or on overhanging vegetation.

Recorded to be on the wing from September through to June.

Status and Conservation

Uncommon and very localised in South Africa. Listed as of Least Concern in the IUCN Red List of Threatened Species.

Distribution

Patchily distributed over much of Sub-Saharan Africa, from West and Central Africa and from East Africa to the NE parts of Southern Africa.

Orthetrum guineense is scarce and sparsely distributed in South Africa where it is restricted to the upland savanna regions of the northern provinces.

Below is a map showing the distribution of records for Guinea 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.