| Radiolarians are a group of pelagic protozoa. occurring in tropical to polar regions and distributed in the surface waters of oceans to thousands of meters depth on the ocean bottom, as one of the dominant microfossil groups found in marine sediments, they are indicators of paleo-oceanographical environments and paleoclimatic variations. The present study which is based on material from collected surface waters of the northern South China Sea, treats of the taxonomy and ecology of the radiolarian fauna of this region and the relationships of radiolarians with their environmental factors. â… . Results of taxonomic study yielded a total of 240 species, belonging to 2 orders including 41 families and 134 genera. Four species are new to science, namely Theopilium paliurum, Clathrocorys gracilis, Artopilium rostrum, Lampromitra lucida. 1).Theopilium paliurum sp. nov.Shell flatly conical, smooth with slight collar stricture. Breadth of the three joints=1:6:1.5. Cephalis subspherical, seven pyramid apical horns arising from the centre of the cephalis, 3-5 times the length of the cephalis. Thorax with three ribs in its wall, and with subregular, hexagonal pores increasing in size towards the girdle. Abdomen flatter than the thorax, without ribs, nearly horizontal, with subregular, square pores, disposed in three to five concentric, circular series. This new species differs from other species of the genus in having 7 pyramid apical horns and in the hexagonal shape of the pores increasing in size towards the girdle.2). Clathrocorys gracilis sp. nov.Cephalis pear-shaped, with very thin thread-like bars interweaving irregularly square pores. Four strong, prismatic radial beams of nearly equal size arise from itsbase centre; beam vertical, straight and prolonged into cephalic horn; three descending radial beams prolonged into three large diverging feet; each foot with cup-shaped structure ramified bar in the proximal section (near cephalis). A few thick branches arise in three meridional planes (between the horn and each foot), interconnecting ramules form the three vertical latticed wings; each wing with a large mesh in the middle, a medium mesh and a small mesh on each side respectively, and three to five parallel arachnoidal rows of small, square, distal meshes. The three walls of the flat pyramidal thorax (between every two feet) are formed by structure similar to that of the wings; an arachnoidal wicker-work of very thin thread-like bars fills out the large meshes.This new species is close to Clathrocorys murrayi (Haeckel, 1887, p.1219, pl.64, fig.8.), but they are different in the arrangement of the wing meshes and in the shape of the cephalic pores, in the latter species, the wing has a small mesh in the middle, and large meshes and small meshes at the side, and has irregularly square cephalic pores, the feet of which do not have cup-shaped bars structure in the proximal section. This new species is similar to Clathrocorys teuscheri (Haeckel, 1887, p.1220, pl.64, fig.10.), but the latter has seven radial beams arising from the cephalic base centre.3). Artopilium rostrum sp. novShell fusiform, about 2 times as long as broad; has one collar stricture and three internal annular septa, one thoracic joint, and four abdominal joints; cephalis subspherical; in the cephalic cavity there are four inner skeletons which come together, one of which pierces through the cephalic wall to become an oblique apical horn, the rest arising from the collar stricture and prolonged into dissociative lattice-wings, the apical horn and three wings are of the same length. Thorax campanulate, 1.5 times as long as first abdominal joint. Abdominal joints unequal in length, the first and second joint equal in length, the other shorter. Mouth of abdomen cylindrical, constricted. Cephalis pores of nearly equal size; thorax and abdomen circular outside with hexagonal frame, regularly arranged.This new species is similar to Artopilium fusiforme (Tan et Tchang, 1976, p.293, textfig.74.), but the latter has thre... |
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