This entry is still on the topic of the latest stamp issue of Malaysia - Garden Flower State Definitives (Re-issue). The 5 sen stamp depicts lotus flower. The more correct scientific name for lotus is Nelumbo nucifera. However, the inscription of the scientific name in the re-issued stamp is Nelumbium nelumbo. I talked about it some time ago (click here to see what I discussed about the lotus).
I personally have brought up (in September 2009) the issue of the scientific name of lotus to the Philately Unit of Pos Malaysia. I also brought up the issue in the Philatelic Society Malaysia (PSM) forum last year in hope that PSM could bring up this matter to the attention of Pos Malaysia. However, the re-issue of the stamp still retains the same scientific name for lotus as that of the original issue.
By the way, lotus and waterlily are two quite different plants. They are belonged to different plant families. Click here to know more about the lotus and waterlily.
