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Acrospyris lingi
Shilov, 1995
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Description - Add description
Acanthodesmid sp.
Remarks: This species demonstrates wide variation in the nature of the five basal spines, ranging from short oblique projections to long downwardly extended legs and connected by horizontal bars with short spines, one of which is illustrated here. Limited time as well as reference materials did not permit the author to make a thorough and detailed comparison of this species with other related forms. However, this species is found in abundance from Core 21 of Site 183, together with Cyrtocapsella tetrapera and the above mentioned Amphymenium sp., thus may have potentiality as a Miocene index taxon.
| | Ling 1973 | Acrospyris lingi
A shell with a well-developed cephalis. Apical spine not developed. Shell thick-walled. Sagittal ring slightly protruding on to the outer surface on cephalis. Cephalis pores of different size, commonly arranged symmetrically relative to the sagittal ring. Diameter of large pores about 20 μm; that of small ones, 8-11 μm. Dimensions of cephalis: length, 55-80 μm; width, 75-100 μm (based on measurements of 20 specimens). Commonly about 6 basal feet. They are connected by transverse bars and form something similar to a thorax with large pores and smaller fine bars. Single pores are visible in places of their junction. When there are 6 basal feet, they form a hexahedron in the section. The diameter of pores is 40-45 μm; thickness of bars, 10-15 μm. Width of "pseudothorax" 100-110 μm; the preserved length 50-60 μm.
Name: This form was first discovered by paleontologist H. Ling, and is named lingi after him.
Occurrences: Sample 145-883B-62X-CC. Lower Miocene. | | Shilov 1995 |
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