Notes on the reproductive behaviour of Anacampseros rufescens

While many of us enjoy the wild flowers we encounter in the field, we seldom are afforded the opportunity to observe all aspects of flowering through to seed dispersal.

Growing some of our wild flowers provides just such an opportunity, but sometimes this is not enough to see the full cycle. As an example, you may have observed that certain of the Iridaceae (Aristea or Moraea) flower only for a part of the day. In the grasslands of the Pondoland Centre of Endemism we often come across Aristea flowering brightly in the morning sunshine but these flowers are all closed when we return along the same route in the afternoon. In contrast we are always pleasantly surprised to see Moraea stricta suddenly appearing in the afternoon when there has been no sign of these flowers in the morning.

We have had the sun-loving succulent Anacampseros rufescens growing in a pot in our garden for some years. Generally in October, when this species tends to start flowering, we spend time on the verandah where we can see the plants in the pot.

Anacampseros rufescens in its natural habitat

The first year we saw a bud being produced, emerging from the unusual wiry white hairs between the rosette of basal leaves and waited avidly to see our first flower. Initially the bud stalk emerges horizontally. When we saw it start to become erect we were convinced that the flower was only a day or so from opening. However we were dismayed to see the fleshy bracts wither and fall away and leave an empty, papery capsule. It was only on subsequent flowering cycles that we realised what had happened.

Empty capsule (centre) and capsule with withered bracts peeling back (left)

Anacampseros rufescens is another of those plants with short-lived ephemeral flowers. They seem to open in mid-morning and by early afternoon those eye-catching bright magenta petals have withered, with only the bracts visible, looking very much like a bud.  This event very nicely coincided with our absence from our observation post and it took us some time to see all the stages from flowering to fruiting. It is only after the flower has been pollinated that the stalk becomes more erect.

As the seeds protected by the fleshy bracts mature, the bracts then themselves wither and drop away exposing the papery capsule in which the seeds are enclosed. Eventually the capsule splits slightly down the middle to expose the seeds to the wind – intriguingly, each seed is enclosed in a small fibrous bag not unlike a triangular tea-bag and the increased surface area provided by the bag allows the seeds to be dispersed by the wind.

Microscope view of Anacampseros rufescens seeds

Seed-filled capsule (centre)

The plant seems to have a very effective pollination process as there is no shortage of small Anacampseros rufescens coming up nearby. This species’ normal habitat is a rather harsh one, as it grows on rock plates near cliff edges. It copes surprisingly well with the hot dry conditions it is often exposed to. This is why we are grateful that it has grown so happily in the much more benign environment of the pot in our garden. We have enjoyed following its reproductive processes from start to finish. 

Early afternoon - petals starting to wither
Note wiry hairs at base of flower stalk

A 2nd visit to Jolivet - more threatened plant species found

What a sudden change in the weather! We had to postpone the visit to Jolivet as the cold and rainy conditions persisted on Thursday and when we made an early start on Saturday we could already feel the heat. After sweltering up the sun-baked hillsides at Jolivet we can well believe that the forecast of 30 degrees Celsius was achieved if not exceeded. However, the hot conditions did little to dampen our enthusiasm as we found a number of other threatened plant species that we did not see on our previous visit a year earlier.

When we arrived at the conservation area at the target site we could see that the other "half" of the grassland had been burned this year, so we decided to travel a different route to explore these newly burned areas.

Our first stop was to revisit the population of a special plant we had discovered last year. At the time we were uncertain of the ID but it it was confirmed to be what we suspected - Riocreuxia flanaganii var. alexandrina, a species red listed as Critically Endangered. Some years back we re-discovered this species in the Vernon Crookes Nature Reserve (see article https://pondolandcrew.blogspot.co.za/2016/01/veld-flora-december-2015-article.html), some 100 years after the species was collected in the area by Rudatis. Last year we saw several of these plants and this year we were able to confirm that the area where they occur on this site is bigger than we thought.

Interestingly, although our visit last year was exactly a year ago, the plants on this occasion had not grown to the stage of producing flowers - we only found one set of buds this time.

Riocreuxia flanaganii var alexandrina buds

Riocreuxia flanaganii var alexandrina leaves

Close by we came across a second rare species for the day, Cyphostemma rubroglandulosa Red Listed as Rare. This collection represents a range extension as the previously known range was from Port St. Johns in the south to Oribi Gorge in the north - some 40 kilometres as the crow flies from this Jolivet site. It is easy to see from this photo why the species was given the name "rubroglandulosa".

Cyphostemma rubroglandulosa

Near the stream we found the odd-looking little fern, Ophioglossum reticulatum.

Ophioglossum reticulatum

An interesting feature of this visit was the number of species of Asparagus we found. None of these is uncommon and all are difficult to adequately depict in a photograph, but it is unusual to have this degree of diversity within one genus in a small area. We found Asparagus asparagoides, A. africanus, A. setaceus, A. falcatus and one other (we await the Asparagus revision).

At the side of a small stream we found Denekia capensis and hidden under the tall unburned grass were groups of Hypoxis membranaceus like little white stars on the ground.

Denekia capensis

Hypoxis membranaceus

We climbed a steep hill - in the hot sun, this was a significant effort -- around a small forest patch and then back down to the vehicle finding some colourful Blechnum tabulare near another stream.

Blechnum tabulare

The forest patch

We then drove up to the top end of the farm and explored on the slopes below. Just before we reached some very attractive shade in another forest patch we came across the find of the day - an orchid in bud which looked very much like the Endangered species Satyrium rhodanthum. There were similar individuals nearby and later, on another hilltop, we found a few more, one with an open flower that helped us confirm its identity. This is another species first collected by Rudatis. This species has a very restricted distribution and is known from only three localities, all under threat to some degree from agricultural activity or unplanned human settlements. This small population will be the fourth known locality for the species.

Getting up close and personal with the Satyrium (photo K Grieve)

Satyrium rhodanthum

Another interesting plant encountered in this area was the Vulnerable Argyrolobium longifolium. Unfortunately, none of the several plants seen had reached flowering stage yet.

After some cool respite in the forest shade we explored the forest fringe further and found Cnestis polyphylla and Memecylon natalense in flower, and an unexpected tree, Seemannaralia gerrardii. 

Cnestis polyphylla

Memecylon natalense

Out on the open grasslands, the most prominent flower was Ursinia saxitilis. Matching this species' yellow colour was Phymaspermum acerosum. Low against the ground we found several Muraltia lancifolia.

Ursinia saxitilis

Phymaspermum acerosum

Muraltia lancifolia

As the trail dropped back towards the river we came across a clump of Kniphofia baurii.
 

Kniphofia baurii

Just before leaving the gate there was a bright patch of Monopsis decipiens.

On the way back we stopped near the site of the old Glen Rosa railway station to see a small population of what used to be known as Begonia rudatisii. This species has been sunk into Begonia homonyma. Unfortunately the soil bank collapsed some time ago, taking most of the plants with it but we managed to find five small plants, one of which was coming into bud.

Begonia (rudatisii) homonyma

It can be seen from the above that the early collector Rudatis (August Gottlieb Hans (1875-1934) was active in the area in the early 1900's. Many of the plants first collected by him are today quite rare, largely as a result of land transformation. We regard it as a great privilege to be given access to a preserved, relatively pristine part of the area once traversed and explored by Rudatis.

Participants: Anne S, Graham G, Kate G.

A quick walk at Beacon Hill

With rain anticipated we had postponed our planned trip to Jolivet until Saturday, and therefore decided to go to Beacon Hill and do some curation in the herbarium. When we arrived the sun was still shining so we decided to have a quick walk near the offices. 

We soon come across a new flush of flowers on the Eriosema untamvunense and these were accompanied by Pelargonium luridum. Scattered amongst these and the ubiquitous Helichrysums were some of the bright magenta flower heads of Cyanotis speciosus. Growing in a rock crevice was a stunted Asparagus densiflorus with a small scattering of flowers.

Eriosema umtamvunense

Pelargonium luridum

 

Asparagus densiflorus

Cyanotis speciosus

Also amongst the rocks was an Eriosemopsis subanisophylla, clumps of Helichrysum diffusum and some well-posed Hypoxis colchicifolia.

Eriosemopsis subanisophylla

Helichrysum diffusum

Hypoxis colchicifolia

In the distance we saw the boundary fence fire break covered in flowers so we worked our way through a wetland to see what had come up there. On the way, we were lucky to find a Disperis paludosa in flower; this is the most northerly occurence of this species recorded so far as it is otherwise restricted to the Western and Eastern Cape. 

 

Disperis paludosa

When we reached the wetland at the bottom end of the fire-break a veritable feast of orchids awaited us. --. Disa similis, Disa tripetaloides, and masses of Satyrium longicauda. This is an interesting late record for Disa similis to be flowering in our area as we started seeing them in late July this year. 

 

An abundance of Satyrium longicauda

Satyrium longicauda

A tall grass-like plant caught the eye with its terminal yellow flowers - Xyris capensis.

Heading back up the fire-break as the weather was starting to threaten, we found ourselves in a cluster of Disa stachyoides. These were accompanied by a Sisyranthus virgatus.

The masses of flowers in the fire-break

Disa stachyoides

Display of Disa stachyoides

Sisyranthus virgatus

Back at the office we could spend the rest of the day filing some recently-mounted voucher specimens.

As we had had some new specimen cupboards installed in the herbarium we look forward to the day we can start re-organising our collection.  This will be done once we have completed capturing data into our BRAHMS database, a task we hope might be completed by the end of the year with the assistance of post-grad student Lindo Tshapa.

Participants: Graham G, Kate G, Uschi T.

Manilkara Meander for more photos

As Geoff wanted to get photos of the Strychnos gerrardii flowers, we paid a quick visit to Manilkara Meander on a bright Sunday morning in a howling gale force wind.

The Strychnos photos were easy to get as the tree is easily accessible. Having done this we then went in search of the Dovyalis lucida trees to see if we could find fruit. The photos I posted on the 18th of September were of male flowers and when we looked on last Thursday these were bare of any fertile material. 

Undaunted, we walked slowly along the cliff edge searching further and eventually found some fruit-bearing trees. To get photos required some precarious cliff-edge perching as can be seen below.

Strychnos gerrardii

Dovyalis lucida fruits

Geoff cliff perching to get his photos

Participants: Geoff N, Graham G.

A first visit to Lower Smedmore

While we have visited the upper reaches of Smedmore Forest on several occasions in the past, it was only once we started botanising along the cliff edges at Manilkara Meander that we realised how large this forest patch was. From the vantage of this section of cliffs we could see that there was fairly easy access to the bottom part of this forest patch and we decided, after the grasslands had been burned in a management burn, to walk this route and explore the forest below.

It required a bit of a scramble from where we had parked down a boulder strewn slope to get to the next plateau which would lead back to the forest. It was gratifying to see small springs and seeps coming out over rocks, a tribute to the rains we have had in early October.
 

Working our way down to the next plateau

On the way down we saw a stunted Erythrina latissima - not a common species in the Umtamvuna Nature Reserve.

Erythrina latissima

Once we got to the flatter area, Uschi found a rock shaped like a motorbike and persuaded Maggie to join her on her new steed.

Uschi's motorbike

The view from the lower plateau is unusual, being half way down to the river, as generally we are either in the upper grasslands or in the forests at the bottom of the gorge.

Umtamvuna gorge from the plateau level

 There were a few scattered trees flowering in the grassland, Senegalia (Acacia) caffra and Apodytes abbottii being the most prominent of these. Although from the fruit capsules we could see signs of a Cyrtanthus having flowered here earlier, there were few other grassland flowers so soon after the burn, the exception being Ursinia tenuiloba.

Senegalia caffra

Apodytes abbottii

Ursinia tenuiloba

 At the edge of the forest we saw the stinging species, Ctenomeria capensis with its odd arrangement of a single female flower succeeded by several male flowers all on a single stalk. 

Ctenomeria capensis

 Not far from this was a cluster of Strophanthus speciosus with its spidery bright orange flowers.

Strophanthus speciosus

Another forest margin species was Euphorbia kraussiana. Under the forest canopy we found several Excoecaria simii in flower and with fruit and Justicia camplyostemon, also in flower. Below it was another stinging plant, Laportea grossa with its attractive white-spotted leaves.

Euphorbia kraussiana

Excoecaria simii

Justicia campylostemon

Laportea grossa 

Many of our forest flowers are cryptic so we were lucky to find Maytenus cordata flowers hidden amongst the leaves. Easier to see were the flowers on a Kiggelaria africana. We encountered three other forest species in fruit -- Bachmannia woodii, Rinorea domatiosa and Suregada africana.

Maytenus cordata

Kiggelaria africana

Rinorea domatiosa

Bachmannia woodii

Suregada africana

There were several tall trees we could see flowering but the flowers and most of the leaves were well beyond reach so we will have to return better equipped to collect specimen material from these tall trees.

On our way back we found a group of Drimia calcarata just starting to flower.

Drimia calcarata

The return trip under Manilkara Meander cliffs

The final climb looms

Once back at the vehicle we did a quick check on the status of the flowers on the big Strychnos gerrardii we had seen in bud along Manilkara Meander and were happy to see the flowers were open en masse.

Strychnos gerrardii

Participants: Anne S, Graham G, Kate G, Maggie A, Uschi T.