The hunt for Searsia longispina: Chapter 2....Target acquired!
This post represents the second chapter in my 'Hunt for Searsia longispina'. The first chapter detailing the reasons I set out on my quest can be found in the link below:
The hunt for Searsia longispina: Chapter 1....Clueless!
At the end of the first chapter, I posted a link to a Searsia species I thought might be Searsia longispina (hereafter referred to as Longispina), and after a lot of discussion and collaboration and referring back to Moffatts work on the Searsia genus, we (thanks @annsymons) came to the conclusion that the species in the observation was indeed Longispina. The observation and related discussion can be found in the link below.
Searsia longispina observation with discussion
(anyone reading this who wants a digital copy of Moffatts work on the Searsia genus, PM me your email address and I'll send it through - it is 10Mb in size)
As a visual learner, it gave me the visual reference I needed for an idea as to what Longispina would look like, but I still needed to see other specimens in the field in order to be able to confidently identify the species. Of course, once I had 'locked' onto Longispina so to speak, I saw Longispina in just about every bush I looked at! That being said, I did have the opportunity to travel through areas where it is known to occur and slowly but surely I started to be able to pick out what I thought was Longispina. On one of these trips, I happened to notice a lone specimen close to the Nanaga Farm Stall - and for anyone who knows this Farm Stall, it is an obligatory stop - their Lamb and Mint pies are worth the detour! On my return trip, I stopped at the bush and took a few photo's which can be found in the link below.
This specimen is only the second 'live' specimen that I can say I have had a good look at, and with all the previous discussions and collaborations with others, I am certain that the above specimen is Longispina.
Of course, the question that I would ask after a confident statement like that would be "Well, what exactly makes it Longispina?" I'm glad you asked!
This next section will list the features that pertain to Longispina, according to the work on the Searsia genus by R.O. Moffatt. Links are provided to observations that best depict (in my opinion) the feature listed.
GROWTH HABIT (architecture)
. Recognised by the habit of forming dense, rounded, multi-stemmed shrubs with pale spinous branches
Photo 1 in the link for habit
Longispina habit
Photo 2 for young branches with long spurs
Long spurs on young branches 1
Photo 1 for young branches with long spurs
Long spurs on young branches 2
Photo 3 for shorter spurs on older branches
Shorter spurs on older branches
BRANCHES
. Finely striate (slender grooves or channels); pale grey-brown to dull yellowish in colour with squarrose (bend slightly downward at the tip), spinous (pointed, sharp) spurs
Photo 5 in the link as an example of a striate branch
Striated branch
Photo 1 in the link for squarrose spurs
Squarrose spurs
LEAVES
. Trifoliate
. Petiolate; petiole semiterete (semi-circular in cross section), canaliculate (grooved) and sometimes margined
Photos 1 & 3 in the link
Petiole 1
Photo 7 in the link
Petiole 2
. Somewhat fasciculate (a bundle or cluster of leaves crowded together) to crowded on spurs
Photo 3 for crowded, fasciculate growth on spurs
Fasciculate leaves 1
Photo 2 for crowded fasciculate growth on spurs
Fasciculate leaves 2
. Glabrous (smooth or glossy i.e. not hairy)
. Often laccate (as if varnished), occasionally glaucescent (blue-grey in colour)
. Lamina (leaf blade) oblanceolate (upperside down spear shape), spatulate (spoon shape) to narrowly obovate (upside down oval i.e. widest in the top half tapering to the base), often convex (curved slightly upwards - like a wide 'V')
. Apex: emarginate (indented at the tip), retuse (blunt or rounded apex with a small notch), mucronulate (tipped with a small point/spine), entire (no teeth or serrations), rounded to subacute (tapered but not sharply pointed)
See photos of leaves in the links
Longispina leaves 1
Longispina leaves 2
. Venation: Kladodromous (veins divide or branch toward the margins), secondary veins curve upwards just short of the margin; midrib slightly prominent above and below
Photo 9 in the link showing venation
Leaf venation 1
Photo 1 in the link showing venation
Leaf venation 2
DRUPE (fruit)
. Shiny, pale green ripening to chestnut-brown
Photos 4 & 6 in the link
Longispina drupes
DISTRIBUTION (where it occurs)
The description below of Longispina's range is quoted directly from Moffatts work:
"Ranges from near Queenstown in the north-eastern Cape, through the eastern, southern and western Cape interior to near Alexander Bay in Namaqualand. It is especially plentiful in the lower Great Karroo becoming scarcer westwards until it is rare in the north-western Cape. There is a single record from Oribi Gorge near Port Shepstone in Natal"
The distribution map of Longispina observations on iNaturalist can be found in the link below
Longispina distribution map
WHAT TO PHOTOGRAPH
"I think this might be Searsia longispina - now what do I do?"
You might end up asking yourself this question while standing in front of tree and want to know what you should photograph in order to be able to get someone to be able to ID it for you.
Remember, it can be really challenging to ID a tree from photographs. In the case of Longispina , and other Searsia spp too, there are a couple of photos which would prove useful in being able to identify it.
Take a look at the sequence of photos in the link below taken of a Longispina bush.
Sequence of photos of Longispina
The observations in the link will give you an idea of what features to photograph - the descriptions of which follow below:
. A wide angle shot of the whole shrub showing the habit (the shape and architecture of the plant)
. A closer shot showing the branching
. A closer shot of a branch showing the arrangement of the leaves/fruit on the branch and spines
. A close up of the upper and underside of some leaves - lay some out on your hand, it doesn't have to be a single leaf
. A close up, backlit shot of a single leaf or leaflet showing the venation
These photos will be a great help to anyone trying to ID Longispina, with 'try' being the operative word - Searsia are a real challenge to identify!
I think that about wraps up my hunt for what has been an elusive species for me. I hope that others will find it a little easier to pick out Longispina now, and hopefully more records will come in giving us an even better idea of what it looks like and where it can be found.
Remember, keep plugging away at trying to ID these plants for yourself, and don't give up too soon!
