Global Review identifies 57 new living species of small marine foraminifera

A global review of small marine animals, called fufaminifera, has identified 57 new resident species, including three in NZ waters. The NZ-led research team used DNA sequences and anatomical structures to define the types of foraminifera living in the sea floor sediments of coastal and shallow coastal areas. This paper has been published in the journal Micropaleontology.

Foraminifera have been around for millions of years and can be used to study environmental changes such as climate change and sea level rise, which makes it important to be able to identify them. Of the more than 200 species in the review, 33 were also found in different parts of the world where fossils show they originated, suggesting they were recently accidentally transported to sea by ships.

In this study, a comprehensive global review of all organisms in four related families of shallow marine foraminifera was carried out. This is only the second global review of a group of foraminifera undertaken using a combination of DNA sequences and morphological characters. The first such global study was conducted by the same NZ-led group of scientists and published in 2021.

The new study found that the greatest diversity of these families occurred in the northwest Pacific Ocean, with 74 species living around the coasts of China and Japan. The next most diverse is the Australian coast with 58 species. The only region lacking any of these families is Antarctica, but 24 species live around the coast of the Arctic Ocean.

Most of the newly recognized species come from the Southern Hemisphere, where they have been little studied over the past 250 years. The first named species in these families were described from the Mediterranean by Carl Linnaeus in 1758. The largest number of new species is from the coast of South Africa (13), followed by Australia (9), Northwest Pacific (3), Mediterranean (5), North Indian Ocean (3), South America (4), New Zealand (5), New Zealand (5), New Zealand (3), South America (5), South America (5), South America (5), South America (5), South America (3), Caribbean (2), Arctic Ocean (1) and the Black Sea (1).

“This new study brings the number of species recognized in these families around New Zealand to 18 years,” Dr Hayward said. “The types of three new New Zealand species were collected from Stewart Island, Tolga Bay and Waitemata Harbour. They are now housed in Auckland and Earth Science New Zealand Museum collections.”

Foraminifera are small marine organisms similar to amoeba but their shells are chambered. Their average size is about 0.4 mm. Foraminifera studied directly in seafloor sands and muds in sediments ranging from estuaries, harbors, bays, and seabeds to depths of approximately 100 m. There are currently 9,000 species of foraminifera in the world and 40,000 described extinct fossil species.

“Foraminifera are widely used to study the effects of pollution and sediment flux on coastal ecosystems. To document sea-level changes that occurred before sea-level changes existed. “We need to be able to identify foraminifera to be able to use them in these applied studies,” said Dr Hayward.

“Foraminifera are the most useful for these studies because their shells preserved in sedimentary sequences provide a record of past environmental changes. The particular foraminifera examined by our group are among the most important worldwide for these studies,” Hayward said.

“Another result of this study was recognition of the enormous extent of accidental human-related transport of marine species around the world over the past few centuries. At least 33 non-native species have been introduced to places on the opposite side of the globe from where they naturally occurred millions of years ago,” Hayward said.