Julia Skimmer (Orthetrum julia)

Orthetrum julia, the Julia skimmer is a species of dragonfly in the family Libellulidae. Its natural habitats are subtropical or tropical moist lowland forests, rivers, and freshwater springs.

The above photo (by David Long) can be viewed in OdonataMAP here. Below is a map showing the distribution of records for Julia 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.

Julia Skimmer OdonataMAP record by Georg Jacobs: http://vmus.adu.org.za/?vm=OdonataMAP-83768


Megan Loftie-Eaton
Megan Loftie-Eaton
Megan is our communications, social media and citizen science coordinator. Prior to her work for the BDI, she coordinated OdonataMAP, the Atlas of African Odonata. A citizen science project run by the Animal Demography Unit, University of Cape Town and funded by the JRS Biodiversity Foundation. She also coordinated LepiMAP, which is the Atlas on African Lepidoptera. Megan is passionate about biodiversity conservation. She is a firm believer in the power of citizen science and getting the public involved in nature conservation.

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