Southern Yellowjack (Notogomphus praetorius)

View the above photo record (by Alan Manson) in OdonataMAP here.

Find the Southern Yellowjack in the FBIS database (Freshwater Biodiversity Information System) here.

Family Gomphidae

Notogomphus praetoriusSOUTHERN YELLOWJACK

Identification

Medium-large size

Length up to 52mm; Wingspan reaches 70mm.

Notogomphus praetorius is distinctive and not easily confused with other species in South Africa. In terms of colouration it most resembles Ceratogomphus pictus (Common Thorntail), however, the Southern Yellowjack has more vivid yellow colouration and is unique among South African Gomphids in having a pair of longitudinal black lines down the length of the abdomen.

The sexes are rather similar but females are more robustly built.

Click here for more details on identification of the Southern Yellowjack.

Notogomphus praetorius – Male
Giants Castle, KwaZulu-Natal
Photo by Alan Manson
Notogomphus praetorius – Female
Umzimkulu Wilderness area, KwaZulu-Natal
Photo by Ryan Tippett

Habitat

Inhabits rivers and streams in mountainous areas, mostly higher than 1000 m above sea level. Occasionally found at well wooded sites, but generally prefers open streams in grassland. Notogomphus praetorius likes clean, clear, flowing water with rocks and an abundance of tall grasses. Very occasionally found at dams.

Habitat – Near Underberg, KwaZulu-Natal
Photo by Ryan Tippett

Behaviour

Commonly found perched on tall grass stems or bushes along the riverbank. Hangs vertically when perched or sits lengthwise parallel to a drooping stem. Frequently rests on rocks close to the water or in the midstream. Notogomphus praetorius is a weak flier and spends much time perched. Flushes easily from the long grass but soon resettles. Somewhat reminiscent of a grasshopper in flight. Both sexes occur in the same areas.

Status and Conservation

The Yellowjack is locally common and listed as of Least Concern in the IUCN Red List of Threatened Species. It is intolerant of habitat degradation and occurs only in pristine, untouched habitats.

Distribution

Notogomphus praetorius has a disjunct distribution. It is mostly confined to the eastern parts Southern Africa, ranging from Malawi, Zambia and the adjoining DRC, down to eastern Zimbabwe and the escarpment areas of South Africa.

Below is a map showing the distribution of records for Yellowjack 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, Ryan Tippett, Rene Navarro & Les Underhill
Dragonfly Atlas: Megan Loftie-Eaton, Ryan Tippett, Rene Navarro & Les Underhill
Megan Loftie-Eaton is our communications, social media and citizen science projects coordinator. Prior to her work for the BDI, she coordinated OdonataMAP, the Atlas of African Odonata. 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 OdonataMAP project. Rene Navarro is the genius behind the Virtual Museum. 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.