Euphorbia prolifera

Euphorbia prolifera Buch.-Ham. ex D.Don, Prodr. Fl. Nepal. 62 1825. (syn: Euphorbia cuneifolia Roxb. [Illegitimate]; Euphorbia linifolia Wall. ex Boiss. [Illegitimate]; Euphorbia nepalensis Boiss. [Illegitimate]; Euphorbia pinus H.Lév.; Tithymalus proliferus (Buch.-Ham. ex D.Don) Soják);

China South-Central; India; Laos; Myanmar; Nepal; Pakistan; Thailand; West Himalaya as per Catalogue of Life;

Indian Subcontinent to SC. China as per WCSP;
Euphorbia species identification requested : 19 posts by 5 authors. Attachments (9) - around 600 kb each.
Please help to identify this Euphorbia species.
Plants are generally 30 - 50cms tall
Flowering and Fruiting from February to May
Altitude - 750 metres asl
Photographed at Hamirpur, Himachal Pradesh

Euphorbia dracunculoides Lam.  ??

This appears to be Euphorbia jacquemontii Boiss. However, it is necessary to check the cyathial characters with the help of my revision of the genus.

Thanks ... But the leaves are very narrow in some non flowering stems upto 3-4mm only and 3cms long, also sir I am doubtful about its low altitude (700metres)
And in this plant there are no distinct white midrib present and this plant looks different to me from that E.jacquemontii that I have posted from Temperate Himalayas.
Here are the images
Attachments (2)

I agree with ... The leaves are really narrow and without white colour along midrib. These characters were not noticeable in the earlier photos. Are these constant in the population? Please check all plants in the population. If it is so, then it cannot be E. jacquemontii. Find out whether there are any substantial differences between the two. If so, it may be a new introduction or a new taxon. 
You can contact Kew or BM. Anyway it is not like any other Indian species.
Other recipients:
Interesting comment by the expert of this genus (Balakrishnan Sir). DSRawat Pantnagar
Interesting comment by the expert of this genus (Balakrishnan Sir). 

Keys in Flora of India vol-23 may help.
Attaching the keys here:
Attachments (4)
Thanks ...,  Sir the leaves are smaller in all plants but on flowering shoot the leaves are larger with inflorescence and also no distinct white midrib is present in leaves like in E.jacquemontii, here are some more photographs sir that I just clicked today.
Attachments (4) - around 600 kb each.

I saw the photograph of the population. It is definitely unlike any other Indian species.
Prepare detailed descriptions and illustrations all floral parts and send to Kew or BM for their opinion.
It is definitely interesting.
While i was checking the Euphorbia subgenus Esula, i came across Euphorbia prolifera which is mentioned in Flora of India.
I visited the plant population recently and after analysing the morphological details including plant height upto 45cm, psedoumbel leaves 4-5, smaller narrow stem leaves gradually becoming large and wide in top stem portion beneath psedoumbel leaves and glands 4-8, horned and also some other characters. 
I came to this conclusion that it is most likely Euphorbia prolifera.
(as no colored image is present on net), i think it is likely Euphorbia prolifera.
I compared its old herbarium images with our plant and found it similar.
Here's the link of herbarium image
I hope it will be confirmed by ...
Euphorbia spinosa ? distribution recored not checked.
Thanks ...  But it is not Euphorbia spinosa as the fruits are not spiny in this plant moreover the glands are also different as they are horned 4-8 in this Euphorbia unlike E. spinosa where glands are not horned.
After perusing with the following, I agree with you: