Note #11 Re-discovering Pelargonium connivens

The renowned botanical explorer John Lavranos was botanizing the Bokkeveld-Hantam plateau in the years 1979 and 1980 when he came across plants of an unknown geophytic Pelargonium. Only 11 years later it was described as Pelargonium connivens by E. M. Marais. Its scientific description suggests an attractive species developing some of the largest flowers amongst all of the ca. 100 described species in the geophytic section Hoarea. A key diagnostic feature of the species is its petals, all pointing upwards and forming a funnel-shaped corolla. No photographs of the species have ever been published and the only material left of the species were the herbarium specimens lodged at Stellenbosch University and Compton herbarium (Cape Town). The drawing of Pelargonium connivens by Ellaphie Ward-Hilhorst in 1984, featured in the species description article, is the last trace of the species existence ex situ. Since the Lavranos collection in 1980, there were no other reports of the species in situ.

Fig. 1: Pelargonium connivens, flowering plant.

Painstaking field-based searches

After years of efforts to locate it, the rediscovery of Pelargonium connivens was only recently confirmed. This task wasn’t made easy by Lavranos, as he reported the type locality as “Rondekop near Nieuwoudtville”, which is particularly blurry as there are over three Rondekops in this area. When contacted by email, John Lavranos gave conflicting information, telling Matija Strlic that the right Rondekop was on the farm Nariesie, while telling me to rather look at the on Wilgenbos, south-west of Calvinia. As nothing could be found on either of the two Rondekops, the species whereabouts remained a mystery. In 2016, giving up on the “Rondekop” clue, I started searching for Pelargonium connivens elsewhere. I eventually found one possible population, but could never confirm its identity, being absent from South Africa during flowering time (December-January). In 2019 I found two other such populations and got assistance from my Nieuwoudtville friends to visit one of them at flowering time. Colleen Rust, John Miles, Susara Steenkamp and Hendrik Kearney joined forces on the 16th of December and to everyone’s upmost pleasure, the party came back victoriously. The flowers they saw were unmistakebly those of Pelargonium connivens (Fig. 1)! A truly marvellous sight.

No more than 25 plants were counted in the largest population of Pelargonium connivens. It should thus be listed as Endangered on the IUCN species list. Being highly palatable to sheep, such a species could once have been a lot more widespread before its decline due to commercial farming.

Fig. 2: Pelargonium connivens, leaves.

Remarkable features and closest relatives

The petals of Pelargonium connivens are its most remarkable feature. Described in botanical terms as connivent (hence the latin name connivens), the petals form a sheath-like structure, giving a funnel shape to the corolla. The corolla is pointing upwards, unlike most Hoarea species where the flowers are pointing sideways. The flowers are also remarkably large for the section Hoarea. The floral display is rather impressive, with 12-30 flowers for each of the 2-7 pseudo-umbellets borne by the main floral scape.

Pelargonium connivens was included in the Aciculatum group in the latest taxonomical revision of the Hoarea section [1], alongside P. aciculatum, P. confertum and P. fasciculaceum. This group is distinguished by its leaf traits (large compound leaves, bi- to tripinnatisect, Fig. 2) but most of all by the structure of the androecia (male reproductive part) with two very short posterior anthers, two recurved lateral ones and two very long anterior anthers, sometimes protruding from the flower.  Species of the Aciculatum group do not overlap in their distribution range.

Confirming the existence of Pelargonium connivens is marvellous news for the Greater Cape Floristic Region, which comprises the most biodiverse mediteranean (Fynbos) and semi-arid (Succulent Karoo) biomes on earth. This species has a certain beauty when its domes of flowers burst out of the sun-scorched soil, its incandescant flowers giving it the appearance of a fiercely burning fire.

By Florent Grenier, Paris, France.

Literature

  1. Marais E. M. (1994), Taxonomic Studies in Pelargonium, Section Hoarea (Geraniaceae), PhD Thesis, University of Stellenbosch.

Citation and Copyright

© The Author. This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
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ISSN 2464-014X.

Cite as: F. Grenier: Re-discovering Pelargonium connivens, Pelargonium Notes, #11 (2020).

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