Amaranthus polygonoides (Introduced)

USA (Florida, South Carolina, Texas), Mexico (Aguascalientes, Campeche, Chiapas, Coahuila, Colima, Guanajuato, Guerrero, Jalisco, Michoacan, Nayarit, Nuevo Leon, San Luis Potosi, Sinaloa, Tamaulipas, Veracruz, Yucatan, Zacatecas), Honduras, Italy (I), Egypt (I), Bahamas, Cuba, Hispaniola, Jamaica, Virgin Isl. (St. Croix, St. Thomas, Virgin Gorda), Lesser Antilles (Antigua, Barbados, Guadeloupe), Aruba, Curacao, Belize, China (I) (Anhui (I), Shandong (I)), S-India (I), Bangladesh (I), Trinidad & Tobago (I) as per Catalogue of Life

Images by (Siva Siva - Identified by Santhan P), (Inserted by Bhagyashri Ranade)

BND 51 51 A 9/11/14 4 posts by 4 authors. Attachments (2)
Please ID this small herbaceous plant that has medicinal/culinary values. 
Photo was taken in Sri Lanka in March 2013.
something I meant to ask you for quite sometime....
if you do not know its id then how do you know its medicinally important...
was it an ethno botanical expedition where the tribal do not know the id?
but then they will have their traditional names.. if so I would like it if you would please share it/ them with this forum 
ps i have enjoyed your pics so far.

It is like Amaranthus spinosus
Amaranthus polygonoides L.- Siru keerai in Tamil 
Image by Siva Siva (inserted by Bhagyashri Ranade)

SL 29 151113 : 5 posts by 4 authors. Attachments (1).
Please ID this creeping plant which is used as a leafy vegetable.
Amaranthaceae? Unfortnately no flowers. Photo was taken in Sri Lanka in Oct 2012.
might be Amaranthus sp.; cf. A. blitoides.
I agree with ... id
Looks different from images of Amaranthus blitoides as per
It should be Amaranthus polygonoides as per
Can you please ID this creeping medicinal herb. Photo was taken in Sri Lanka in Nov 2012.
Really difficult to ID. Image quality not so good !
Amaranthus polygonoides