Brown Duskhawker (Gynacantha villosa)

View the above photo record (by Gary Brown) in OdonataMAP here.

Find the Brown Duskhawker in the FBIS database (Freshwater Biodiversity Information System) here.

Family Aeshnidae

Gynacantha villosa – BROWN DUSKHAWKER

Identification

Very large

Length up to 77mm; Wingspan attains 114mm.

The sexes are very similar but males are slightly brighter, have a 4-celled anal triangle and a narrower waist.

Most likely to be confused with Gynacantha manderica and Gynacantha usambarica.

Gynacantha villosa can be told apart by the double cell row between the R2 and R3 veins in the forewings. The other two species have only a single row of cells. The Brown Duskhawker is also unique among Southern African species in having a black ring around the metastigma, and in males, a four-celled anal triangle.

Click here for more details on identification of the Brown Duskhawker.

Habitat

Occupies coastal and especially swamp forests along the northern KwaZulu-Natal coast. Found in the vicinity of streams and pools, surrounded by dense vegetation. Further inland it inhabits riverine forests fringing large savanna rivers.

Behaviour

Elusive, crepuscular and seldom seen. Rests by day in dark, shaded undergrowth. Most active at dawn and dusk when it emerges to hunt over pools, streams and clearings. The flight is fast and powerful. The Brown Duskhawker is sometimes attracted to lights in the early evening. Hangs from a perch when at rest.

Status and Conservation

Uncommon to rare and localised in South Africa, where it is listed as Vulnerable in the IUCN Red List of Threatened Species. Gynacantha villosa is generally intolerant of habitat degradation and is mostly found at undisturbed sites.

Distribution

The Brown Duskhawker is found in East and Southern Africa. Extending from Ethiopia in the north down through Uganda, Kenya and Tanzania to Zambia, Malawi, Mozambique, Zimbabwe and marginally into South Africa.

Below is a map showing the distribution of records for Brown Duskhawker 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.