Eastern Forestwatcher (Notiothemis jonesi)

The photo above (by John Wilkinson) can be viewed in OdonataMAP here.

Notiothemis jonesi, commonly known as the Eastern Forestwatcher is a dragonfly in the family Libellulidae.

Identification

Small size

Length up to 33mm; Wingspan attains 51mm.

The males of this species are unmistakable within the sub-region. The combination of mottled black and blue-green colouration, bright turquoise eyes and pale band on the S7 are diagnostic.

Females are easily confused with those of Tetrathemis polleni. The two species differ in the shape of the discoidal cell (DC) in the fore wings. Notiothemis jonesi has a triangular DC, while Tetrathemis polleni has a four-sided DC.

There is another closely related species, Notiothemis robertsi, found in the tropical forests of East, Central and West Africa.

Notiothemis jonesi – Male
Amanzimtoti Bird Sanctuary, KwaZulu-Natal
Photo by Christopher Peter Small

Habitat

Frequents shady, slow moving stretches of forested streams and pools. It occurs in coastal, riverine and swamp forests in South Africa.

Behaviour

Perches on twigs or vegetation over the water in dappled light. Very alert and weary, heading to the canopy if disturbed. Females are seldom encountered.

Status and Conservation

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

Distribution

Notiothemis jonesi is found in the tropical and subtropical parts of Eastern and Southern Africa. It occurs from Kenya to South Africa. It has also been recorded in Swaziland, Mozambique, Zambia, Malawi, Tanzania and Uganda.

Below is a map showing the distribution of records for Eastern Forestwatcher 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.