Morphology of four Miliolinella species (Foraminifera, Protozoa)with description of a new species, Miliolinella obesa nov. spec., from the tropical West Pacific Ocean

摘要

Foraminiferal oozes were sampled from the tropical West Pacific seamount and seabed of deep sea, by a remotely operated vehicle (ROV) in December 2014 and March 2016. Using standard morphological method, four Miliolinella species, including Miliolinella obesa, M. circularis, M. suborbicularis and M. subrotunda were described. Among the four species, M. obesa is a new species. It is a large member (about 500 μm in length) of the genus. This species is characterized by having a very stout and transverse broadly circular outline, and its body width is greater than the body length. In addition, its chamber demarcations are obscure from the exterior appearance. Three chambers are unclearly visible on one side and two chambers are visible on the opposite. Finally, we provided very detailed taxonomic microphotographs and the ecological distribution information for each species.