Sir,
ID key of various Amaranthus in the Bengal Plants (i am trying to grasp; and for future ref.) :-
Bracts awned or setaceous, equalling or exceeding the sepals; utricle dehiscent, circumscissile; leaves long-petioled :-
(i) stamens 5, sepals 5, ...with spines... ---------- A. spinosus L. (an erect spinescent herb)
(ii) stamens 5, sepals 5, ... stems striate;
leaves acute or acuminate; spikes thyrsoid; bracts recurved, much exceeding the oblong-lanceolate, acuminate sepals -----
A. paniculatus L. (a tall robust annual, cultivated)
(iii) stamens 5, sepals 5, ... stems striate;
leaves obtuse, rarely acute; spike thyrsoid; bracts hardly recurved, not much exceeding the obovate, mucronate sepals -----
A. caudatus L. (a tall robust annual, cultivated)
(iv) stamens 3, sepals 3, leaves obtuse or emarginate; erect;
flowers clustered in lower axils and also forming a long terminal spike; sepals long awned; stems branching above the middle -----
A. gangeticus L. (an erect stout annual, very variable in colour and shape of leaves, cultivated)
(iv b) ......do......; stems branching near the base; yielding several crops annually -----
A. gangeticus var. tristis ( annual with ,many prostrate branches, cultivated)
(v) stamens 3, sepals 3, leaves obtuse or emarginate; diffuse;
flowers clustered, all axillary, sepals short-awned --------
A. mangostanus L. (a diffusely branched annual, perhaps a feral state of
A. gangeticus var.
tristis)
Bracts acute, hardly awned, shorter than sepals; utricle indehiscent or rarely dehiscent; leaves obtuse, rounded or notched :-
(vi) stamens 3, sepals 3;
utricle acute at the tip, rugose; clusters axillary and in terminal panicled slender spikes; leaves green -----
A. viridis L. (a slender annual)
(vi b) ..... do .........; leaves with a pale crescentic , transverse band ---------
A. viridis var. fasciata (a slender annual)
(vii) stamens 3, sepals 3;
utricle blunt at the tip, membranous, orbicular or broadly ovate; procumbent;
leaves small, 2-lobed; clusters
all axillary -------
A. blitum L. (a procumbent annual weed)
(vii b) .....do ......; tall, succulent; leaves large, oblong or rounded;
clusters axillary and in terminal, simple or lobed spikes ----------
A. blitum var. oleracea (a tall succulent annual, cultivated)
(viii) stamens 3, sepals 3; utricle blunt at the tip, utricle rugose, ovoid, indehiscent or dehiscent; leaves obtuse, rarely retuse or 2-lobed;
clusters all axillary -----
A. polygamus L. (a prostrate annual weed)
(ix) stamens 2, sepals 2; utricle orbicular, compressed;
clusters minute, all axillary; leaves small, linear-oblong, with rounded, obtuse or 2-lobed tip -----
A. tenuifolius Willd. (a prostrate annual weed)
F. B. I has one more -
Amaranthus caturus Heyne = tall, glabrous, leaves long-petioled elliptic-lanceolate acuminate thin, nerves very slender, clusters small globose soft green in very long and very slender axillary simple and terminal panicled spikes....... stem 2-3 ft., very slender......... Deccan Peninsula
Thank you,
Regards,
surajit