Introduction: Sea urchins in the order Spatangoida are most diverse group of extant echinoids. Objective: Describe a new genus and species from abyssal depths, add records for known species. Methods: Specimens were collected during several cruises at different areas southwestern Atlantic Ocean (SWAO), among 37-55° S latitude depths ranging 55 to 3 000 m. We present morphological ultrastructure ...

The regular echinoids were recorded from Chennai Coast,Tamilnadu, South India and the animals were belong to 4 families, 5 genera and 5 species. An identification key to generic level and synoptic description are provided. Temnopleurid sea urchin Salmaciella oligopora (Clark, 1916) was recorded for the first time in 20-30m depth between Chennai and Pondicherry Coasts, South East Coast of India....

Brachiopod faunas from the Aptian- Cenomanian Vezk section in southwesternIran comprise ten species in six genera, namely Sellithyris cenomanensis, Sellithyris tornacensis, Sellithyris phaseolina, Phaseolina phaseolina, Tropeothyris sp., Concinnithyris subundata, Kingena arenosa, Cyclothyris difformis, Cyclothyris sp. and Cyclothyris compressa. All species are recorded for the first time from t...

When food-limited, Diadema antillarum increases the relative size of Aristotle's lantern compared to the size of the test. This is accomplished primarily by decreasing the size of the test: the demipyramid grows at a reduced rate as the test shrinks. These results suggest that an altered relationship between demipyramid and test size can provide evidence for food-limitation in field populations...

This database includes over 7,100 georeferenced occurrence records of sea urchins (Echinodermata: Echinoidea) obtained from samples collected in the Southern Ocean (+180°W/+180°E; -35°/-78°S) during oceanographic cruises led over 150 years, from 1872 to 2015. Echinoids are common organisms of Southern Ocean benthic communities. A total of 201 species is recorded, which display contrasting depth...