Voltski, I., Weinerb, A.K.M., Tsuchiya, M., Kitazato, H. (2018). Morphological and genetic description of Syringammina limosa sp. nov., the first xenophyophore (Foraminifera) from the deep Sea of Okhotsk. Deep Sea Research Part II: Topical Studies in Oceanography. 154: 32-46.

353364

10.1016/j.dsr2.2017.12.001 [view]

Voltski, I., Weinerb, A.K.M., Tsuchiya, M., Kitazato, H.

2018

154: 32-46

Publication

Available for editors  

Foraminifera are one of the most abundant taxa in the deep sea. Our sampling in the Sea of Okhotsk and the adjacent Pacific during the SokhoBio cruise revealed a large number of species confined to this ecosystem. Many Foraminifera below the CCD (carbonate compensation depth) are characterized by the formation of agglutinated tests, made up of material from the surrounding environment. Xenophyophores represent an important group of large agglutinated monothalamous Foraminifera with fragile tests that can measure several centimeters in size. In the deep Kuril Basin of the Sea of Okhotsk, we retrieved an undescribed xenophyophore, dwelling on diatomaceous ooze at a depth of about 3300?m. The species Syringammina limosa sp. nov., described herein, possesses a soft, agglutinated test made up primarily of fine sediment particles, diatom fragments and sponge spicules. It measures about 3?cm in diameter and is characterized by a complex 3D structure consisting of tubular elements proximally fused into continuous, folding plates. In a phylogenetic tree based on small-subunit ribosomal DNA (SSU rDNA) sequences it branches as the sister to Syringammina corbicula. All specimens found were considered alive at the moment of collection, due to the presence of intact cytoplasm-containing strands (granellare) within the test interior. The granellare contained copious amounts of intracellular crystals (granellae) with a wide range of different shapes. Electron microscopy and analysis of the elemental composition identified Si, Al and Fe in the granellae of the holotype, and the xenophyophore-typical barium sulphate (barite) granellae in another specimen. While the presence of minerals, gathered from the environment, is typical for the cytoplasm of xenophyophores, their actual role in the organism remains unclear. Despite many species of xenophyophores having been described recently, the discovery of a new species of these fascinating protists in the Sea of Okhotsk suggests that there is still a large amount of undocumented diversity.

Foraminifera

RIS (EndNote, Reference Manager, ProCite, RefWorks)
BibTex (BibDesk, LaTeX)

[Back to search]