Cynanchum viminale subsp. brunonianum

Cynanchum viminale subsp. brunonianum (Wight & Arn.) Meve & Liede, Kew Bull. 67(4): 754. 2012 (syn: Sarcostemma brunonianum Wight & Arn.; Sarcostemma viminale subsp. brunonianum (Wight & Arn.) P.I.Forst.);
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India, Sri Lanka, Indo-China to Peninsula Malaysia (Langkawi), Philippines (Luzon), N. & E. Australia as per POWO;
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Common name: Leafless East-Indian Vine • Hindi: सोमा Soma, सोमलता Somlata • Kannada: braahmi, hambu balli, hambu kalli • Sanskrit: सोमा Soma, सोमलता Somlata, सोमवल्ली Somavalli • Tamil: kodikkalli, somamum • Telugu: aaku jemudu, aku jemudu
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ANAPR56 Sarcostemma sp. for identification : 12 posts by 7 authors. Attachments (9)

Family: Apocynaceae
Date: 19th April 2015
Place: Sathyamangalam Tiger Reserve, Tamil Nadu
Habit: Climber
Habitat: Deciduous forest

Following Sarcostemma species I could find in efi:

Cynanchum viminale (Syn: (=) Sarcostemma acidum (Roxb.) Voig; (≡) Sarcostemma viminale (L.) R. Br.))

Leptadenia pyrotechnica (Syn: Sarcostemma pyrotechnicum (Forssk.) Schult.)
Oxystelma esculentum (Syn: Sarcostemma esculentum (L. f.) R.W. Holm);

This is a species of Sarcostemma. it may be S. viminale.

Thanks to … for an introduction to this genus

I have seen several others among the milkweed climbers. Oxystelma esculentum, Rosy milkweed climber is quite distinct.

As per PlantList :

Cynanchum viminale (L.) is an accepted name. and S. viminale (L) R. Br is a synonym to this species
Sarcostemma acidum (Roxb.) Voigt is a (separate) accepted name;

Are these the only two milkweed climbers where the leaves are scale-like ?

Three species are described with few images under Sarcostemma at Flowering plants of Kerala.

The following links with Images and descriptions may also be useful to distinguish .

link to Cynanchum_viminale_subsp._brunonianum (Wight & Arn.) (Australia)
link to Sarcostemma acidum (Roxb.)Voigt. (India)

Thanks … I actually am not certain of the various floral parts and how to describe them- corona etc. and hence am waiting for someone to tell me what it is and how it can be used to identify the species and if further details are necessary.

Please check for S. intermedium.

I have already sent my view in a personal correspondence to Anurag Ji. That particular personal correspondence covered several issues, not particularly this plant though it featured in our discussion. This is another entirely unknown genus to me. I thank Anurag ji for introducing.

I copy here what I sent him yesterday –

It is real tough. My guess is Sarcostemma brunonianum Wight & Arn. My guess is based on –

lateral umbels
canescent pedicel and calyx
10 lobed outer corona (my guess is that it is the part just above the calyx, having a smaller lobe between two larger lobes
5 fleshy inner corona

Please check probability, because I may be wrong, you can see how little response you have received in eFI. Please read carefully Wight’s account in all descriptions attached herewith, including that of S. viminale (in S. brevistigma?). Also check following links –

For me S intermedium as identified by … seems to be correct. See this link as well:
http://opendata.keystone-foundation.org/sarcostemma-intermedium-decne

Gamble differentiates S. intermedium from S. brunnonianum as follows:

1a. Umbels always terminal; pedicels glabrous or slightly puberulous — S. intermedium

1b. Umbels usually lateral; pedicels crispate villous –-S. brunnonianum

Based on these characters your photos indicate that the plant is Sarcostemma brunnonianum.
There are other differences given by Gamble, which are not discernible in your photos.

Surajit sir, I went through the books and your links, I am afraid I still do not understand the structure well enough to realise what I am looking at when it comes to the anthers/styles etc. I can only tell where the pollinia and stigma are present.
But I will take your’s and … identification- Sarcostemma brunnonianum.
…, thank you for your help.

It was my guess only. I too can’t tell you which part of this plant-flower is what. But perhaps I can make out which one is outer corona and which one is inner, besides stigma.

The point in favour of S. viminale (brunonianum is a subspecies) is = in DSC_0061.jpg = pointed and bifid stigma (can’t say if it is prolonged one) = ref. Wight

But, your DSC_0101.jpg seems to show a few terminal umbels as well (please see attached highlighted part of your photograph) which I missed earlier.

The point against S. intermedium is = the flowers are pure white in that species = ref. Wight

Please also check description and other aspect of Cynanchum sarcomedium in the attached pdf file.

Here are two more links which can be useful –

… all are equally respected to me. I only suggested probability. I do not know what this species can be. Based upon the flower size (described in the link1 above) and other features you check one more time and tell me what this species can be. I want to learn.
Attachments (4)

Now that I am going through the 0101 photo, I can spot various other spots where there are terminal umbels. It would put the characters as intermediate between the two species given in this. This is a little perplexing for me.

Agreed that S. intermedium may very well not be it.

Also, I feel that .5 mm style could not be called elongated and thus may not be applicable to this plant according to the description of Cynanchum sarcomedium in the paper!

I feel we should leave this here as- more points in favour of S. viminale and lesser in favour of the other species (mainly S. intermedium).

In case I should find this plant again elsewhere or another species, I will make sure to record a lot more details.
What do you think sir?

A few terminal umbels doesn’t pose problem, Anurag Ji, for Gamble’s,KEY tells us “usually lateral” in S. brunonianum.
But where did you get 0.5 mm style?
Another point against S. intermedium is the corona lobes in your species may not be called acute, outer ones look like (sub)obtuse and the inner ones acuminate. But, I am not sure.

Thank you for pointing out Gamble’s key sir.

And the shape of the corona lobes.

Since the part outside which is bifid is the stigma, and the ovary is superior in Apocynaceae, I would assume that the style (in photo WP_20150420_088) Would begin just above 12.3 cm and end at around under 12.4 cm. the difference would give me roughly .5mm length of style and the remaining protruding bit- bifid stigma.
Or have I misunderstood the structure sir?

Why not 1 mm …?

That is possible sir. I have looked at it wrongly.

POWO lists numerous subspecies of Cynanchum viminale.

Out of this for two of them they give distribution in India:

Cynanchum viminale subsp. brunonianum (Wight & Arn.) Meve & Liede

Cynanchum viminale subsp. stocksii (Hook.f.) Meve & Liede

I could not find out the difference between the two, but images match with those at Cynanchum viminale subsp. brunonianum (Wight & Arn.) Meve & Liede