Calamus
The genus Calamus (374 spp.) is the largest palm genus. It consists of pleonanthic, dioecious palms, most often with clustered, high-climbing stems and pinnate leaves; inflorescences bearing unisexual flowers; fruits covered by imbricate scales.
Calamus has a very wide distribution, occurring in tropical west and central Africa, India, Burma, south China through the Malay Archipelago to Australia and Fiji. The greatest abundance and diversity of species has been reported for the archipelagos of Malesia (Sunderland, 2012).
The genus ranges from sea-level to over 3000 m (in Asian species), although clearly most diverse in the rain forests at low altitudes (Dransfield et al., 2008).