Ischaemum, Linnaeus (1753 b:, 1049

Landge, Shahid Nawaz & Shinde, Rajendra D., 2022, Ischaemum dioecum (Poaceae: Andropogoneae): the most strangest new species from Northern Western Ghats, Maharashtra, India, Phytotaxa 533 (5), pp. 237-255 : 239

Key to allied genera of Ischaemum

1. Sessile spikelets suppressed, only pedicelled spikelets developed ....................................................................................................2

1. Sessile and pedicelled spikelets both are well developed (latter sometimes reduced but pedicel not curved) ..................................3

2. Rhachis of the raceme inarticulate; glumes keeled, ciliate or glabrous on the back .............................................................. Dimeria

2. Rhachis of the raceme articulated (jointed and fragile); glumes rounded not keeled, with a tuft of hairs on the back ....................... ............................................................................................ Pogonachne (monotypic genus narrow endemic to Maharashtra, India)

3. Pedicelled spikelets represented by linear curved pedicel; lower glume of the sessile spikelet covered all over with transverse much raised ridges which are often broken up into teeth or wart-like papillose excrescences, not keeled ............................... Thelepogon

3. Pedicelled spikelets mostly well developed, if reduced then lower glume of the sessile spikelet not as above, keeled....................4

4. Inflorescence racemiform-panicle; spikelets of each pair similar or hermaphrodite, glumes not winged; lower glume of the sessile spikelet keel-less and prominently ribbed-veins .......................................................................................................... Spodiopogon *

4. Inflorescence spiciform-raceme; spikelets of each pair dissimilar or heteromorphic (if homomorphic then glumes winged see Ischaemum ).........................................................................................................................................................................................5

5. Geniculate awn present.......................................................................................................................................................................6

5. Geniculate awn absent............................................................................................. Glyphochloa (endemic to Western Ghats, India)

6. Lower glume of the sessile spikelet with a distinct median longitudinal groove...............................................................................7

6. Lower glume of the sessile spikelet convex or flat or may be somewhat depressed but never with a distinct median longitudinal groove as mentioned above .............................................................................................................................................. Ischaemum

7. Lower glume of the sessile spikelets with two vertical rows of hair; upper glume of the sessile spikelets with a tuft of hairs at or above the middle; upper glume of both the spikelets are wingless ...................................................................................................... ............................................................................................ Triplopogon (monotypic genus narrow endemic to Maharashtra, India)

7. Lower glume of the sessile spikelets without two vertical rows of hair; upper glume of the sessile spikelets without any tuft of hairs; upper glume of both the spikelets with wing-like crest........................... Andropterum (monotypic genus endemic to Africa)