Diversity of sand inhabiting marine ascomycetes in some tourist beaches on Cozumel Island, Mexico

• We recorded seven species of marine ascomycetes in five beaches in Cozumel Island.
• Lindra thalassiae and Corollospora maritima were the top two dominant species.
• Our results showed that the diversity values differed among beaches.
• Corollospora gracilis and Lulworthia grandispora are new records for Cozumel Island.

Globally marine fungal diversity is poorly known, especially in Mexico. We evaluated the diversity of marine ascomycetes on five tourist beaches on Cozumel Island in September 2004, and in February 2007. Fifty sample units were collected randomly from each beach during each sampling time. Seven species were recovered, of which Lindra thalassiae and Corollospora maritima were the most dominant species. Corollospora gracilis and Lulworthia grandispora are new records for Cozumel Island. The highest diversity value was found in San Francisco beach, probably because the surrounding coral reefs are an important source of a wide variety of substrata for these fungi.