Boulder Jewel (Platycypha fitzsimonsi)

View the above photo record (by Bertie Brink) in OdonataMAP here.

Find the Boulder Jewel in the FBIS database (Freshwater Biodiversity Information System) here.

Family Chlorocyphidae

Platycypha fitzsimonsiBOULDER JEWEL

Identification

Small size

Length up to 34mm; Wingspan attains 54mm.

Adult males are distinctive and easily recognised. The bright red and black colouration is diagnostic. Only the upper parts of the last four abdominal segments are vivid blue.

Females and immature males are very similar to those of Platycypha caligata. They are best identified by their association with the males.

Click here for more details on identification.

Platycypha fitzsimonsi – Moordkuil River, Western Cape
Photo by Ryan Tippett
Platycypha fitzsimonsi – Kogelberg Nature Reserve, Western Cape
Photo by Corrie Du Toit

Habitat

This species frequents swift, rocky streams and rivers in both open or forested/wooded habitats. It is most common in fynbos and grassland. Often found alongside the more common Dancing Jewel (Platycypha caligata), but generally prefers more open habitats. The Boulder Jewel is the only Platycypha species in the Western Cape.

Habitat – Kogelberg Nature Reserve, Western Cape
Photo by Sharon Stanton
Habitat – Oribi Gorge Nature Reserve, KwaZulu-Natal
Photo by Ryan Tippett

Behaviour

Territorial males perch low down, close to the water. They sit predominantly on rocks but will also rest on overhanging or emergent twigs, reeds and grass. The females are usually found alongside the males. Boulder Jewels are perch hunters, taking short, low flights across the water. Platycypha fitzsimonsi males are well noted for having an eye-catching courtship display. The male hovers in front of a perched female. His legs hang down vertically as he twists or waves them, alternately flashing red and white.

Active from October to May (See Phenology below).

Status and Conservation

Endemic to South Africa. It is a fairly common but localised species and is listed as Least Concern on the IUCN Red List of Threatened Species. It is moderately sensitive to habitat damage. It is intolerant of turbid and dirty water, but does occur on rivers with some alien plant growth.

Distribution

Platycypha fitzsimonsi occurs locally in cooler mid-altitude areas along the escarpment, from the Western Cape to Mpumalanga.

Below is a map showing the distribution of records for Boulder Jewel 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.

1 Comment

  1. Good work!
    Can the average altitude for all records (in this specific instance) be calculated and communicated, please.

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