Review Commelinaceae genus Amischotolype. 

Cf. Amischotolype hookeri (Hassk.) H. Hara

 Jose Luis is correct. It is a Commelinaceae plant. Most probably Amischotolype hookeri. Please have a look at these links.

https://www.researchgate.net/publication/302479173_A_synopsis_of_the_genus_Amischotolype_Commelinaceae_in_India_with_one_new_record_A_monosperma_CB_Clarke_IM_Turner_from_Andaman_Nicobar_Islands_and_lectotypification_of_A_hookeri_Hassk_H_Hara

https://www.researchgate.net/publication/272182796_A_taxonomic_account_of_Amischotolype_Commelinaceae_and_notes_on_the_occurrence_of_Porandra_in_India

https://www.researchgate.net/publication/270279483_A_SKETCH_ON_THE_FAMILY_COMMELINACEAE_OF_WEST_BENGAL

Article A synopsis of the genus Amischotolype (Commelinaceae) in Ind...

Article A taxonomic account of Amischotolype (Commelinaceae) and not...

Conference Paper A SKETCH ON THE FAMILY COMMELINACEAE OF WEST BENGAL.

Family - Commelinaceae

Genus - Amischotolype

 I Agreed aravind sir...Amischotolype hookeri.

thanks to all

Thanks to all specially aravind sir. According to literature review by myself so far this species not yet recorded in Bangladesh by100 years.  Flora of British India is the only references.

Need some expert opinion:) 

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