Probing the Enigmatic Record of Gracilaria disticha (Gracilariales, Rhodophyta) Reported from Sibuyan Island, Philippines

Lawrence  M. Liao,; Jeric  B. Gonzalez,

Probing the Enigmatic Record of Gracilaria disticha (Gracilariales, Rhodophyta) Reported from Sibuyan Island, Philippines

Abstract:

The marine red seaweed genus Gracilaria is among the most species-rich that is widely distributed throughout the Philippines. While many species are common and well characterized, there are a number of those poorly known and often based on single and overlooked reports. One such little known species is Gracilaria disticha (J. Agardh) J. Agardh which was first collected in 1975 from Sibuyan Island in Romblon. An exhaustive search and comparison with published descriptions and scanned images have revealed a misidentification. Results suggested that the Romblon samples are typical of the common Philippine species, Gracilaria edulis (Gmelin) Silva, and that the record of G. disticha should be removed from the Philippine seaweed flora. This report emphasizes the importance of thorough verification of records based on examination and comparison of well-preserved samples by experienced taxonomists and exhaustive literature searches.

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