Clubbed Talontail (Crenigomphus hartmanni)

The photo above (by Alan Manson) can be viewed in OdonataMAP here.

Crenigomphus hartmanni, the Clubbed Talontail, is a species of dragonfly in the family Gomphidae.

Identification

Medium-large size

Length up to 54mm; Wingspan attains 72mm.

Males are very similar to Crenigomphus cornutus. The Clubbed Talontail is best identified by the small but distinct foliations on segments 8 and 9 of the abdomen. Crenigomphus cornutus lacks these.

Crenigomphus hartmanni – Mkuze River, KwaZulu-Natal
Photo by Ryan Tippett

Habitat

Inhabits flowing rocky rivers and streams in savanna regions. Prefers shallow, swift flowing sections with pebbles or gravelly substrate. Often found in relatively open areas with tall clumps of grass and bushes.

Habitat – Mkuze River, KwaZulu-Natal
Photo by Rowan Poortier

Behaviour

Prefers to perch prominently on top of grass or reed stems and bushes. May also perch on rocks close to the water. Flies low and fast over the water or vegetation when hunting or if disturbed. Hunts from a perch and quickly returns to settle again. Frequently found on grass or bushes far from water, especially after breeding or late in the season. Females occur in the same area as the males.

Status and Conservation

A fairly common but localised species. It is listed as of Least Concern in the IUCN Red List of Threatened Species. The Clubbed Talontail is only found in undisturbed habitats.

Distribution

Crenigomphus hartmanni is found in East and Southern Africa, from Kenya and Uganda in the north down to South Africa. In South Africa it is mostly restricted to the Eastern interior, but also occurs sparsely along the Orange River and at scattered locations in the Eastern and Western Cape.

Below is a map showing the distribution of records for Clubbed Talontail 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.