Salenia trisuranalis
Salenia trisuranalis
Summary
Salenia trisuranalis was a small regular sea urchin with a near-radial body plan and a rigid test carrying movable spines. Unlike burrowing heart urchins, saleniids were epibenthic echinoids that lived on the sea floor, where a combination of grazing and detrital feeding is a reasonable ecological interpretation from their regular echinoid construction.
The species is especially informative because saleniid taxonomy depends heavily on the apical system and test plating. London Clay material is therefore most useful when the upper part of the test is preserved; isolated spines or worn plates are much less diagnostic.
Quick Identification
Look for: a small, regular sea-urchin test with strong radial symmetry, a conspicuously developed apical plate system on top, narrow ambulacral zones and rows of prominent tubercles for the spines.
Diagnostic Features
- Test regular and subglobular to low-domed, lacking the heart-shaped outline of spatangoids.
- Apical system proportionally large and a major part of species-level identification.
- Ambulacral zones narrow, with paired pore series arranged radially.
- Interambulacral plates bear conspicuous primary tubercles.
- Plate sutures and apical plating must be sufficiently preserved to separate the species from other saleniids.
Fossil Details
Similar Species
Recorded Fossil Sites
No fossil-site occurrences have yet been recorded for this species.
References
- Lewis, D. N.; Jefferies, R. P. S. (1980). Salenia trisuranalis sp. nov. (Echinoidea) from the Eocene (London Clay) of Essex, and notes on its phylogeny. Bulletin of the British Museum (Natural History), Geology, 33(2), 115–121 View reference