Alloteropsis (from the Greek allotrios ("strange") and opsis ("appearance")) is a genus of Old World plants in the grass family.

[4][5][6][7][8][2][9][10] The group is widely distributed in tropical and subtropical parts of Africa, Asia and Australia, as well as on certain islands in the Indian and Pacific Oceans.

Phylogenetic reconstructions of the evolutionary relationships between these species have led to two hypotheses about how photosynthetic pathways have evolved within the group.

First, C4 photosynthesis evolved in three lineages within this group, leading to independently derived realisations of this pathway (the hypothesis of multiple C4 origins).

[13][14] Secondly, that there was a single origin of C4 photosynthesis within the genus, and the C3 taxon, A. s. ecklonia, was subsequently derived from a C4 ancestor (the reversion hypothesis).