ABOVE: Mangifera torquenda  (Local name: Bunitan) collected from the botanical trail at Deramakot forest reserve in Sabah.  

Dispersal of M. torquenda seeds: Unlike the majority of mangoes in Borneo the seed is relatively smooth without hairs attaching the pulp to the seed. The evolutionary reason for hairy seeds  surrounded by soft sweet pulp is that they force the intended disperser to swallow the the whole fruit.   Fruit that is swallowed and the seed later defecated will be dispersed a relatively long distance from the parent tree.

One dispersal problem of large mangoes with hairy seeds such as Bambangan Mangifera pajang and Beluno Mangifera caesia is that they are so large they can only be swallowed whole by elephants and rhinos both now rare in Borneo.

The smaller size of the M. torquenda seeds opens up a new range of potential primary dispersers including deer and Sun Bears, which will regurgitate the seeds after consuming the pulp. The hard shelled seeds  can then be secondarily dispersed by rodents such as squirrels and porcupines.

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Mangifera torquenda 3P7A0263.JPG

 

CCI07122018

Tree Flora of Sabah & Sarawak VOL. 2 (1996) 

 

35-46 Forest fungi- Seed Size - Copy