Larvae of marine invertebrates either arise from small eggs and feed during their development or arise from large eggs that proceed to metamorphosis sustained only from maternal provisioning. Only a few species are known to possess facultatively feeding larvae. Of about 250 echinoid species with known mode of development, only two, Brisaster latifrons and Clypeaster rosaceus, are known to devel...

Sediments and fossil content of Gediz Delta (Eastern Aegean Sea-İzmir) were examined from the samples collected three drilling cores west (seaward) to east (landward) delta. Each core contains Quarternary marine deposits with a fauna foraminifers, bivalves, gastropods, echinoids, ostracods at bottom Quaternary continental delta top. According our Electron Spin Resonance (ESR) age model sediment...

A well-supported phylogeny of echinoderm classes has eluded morphological, embryological, molecular, and combined analyses. From this body of work it is apparent that (i) echinoids (sea urchins) and holothuroids (sea cucumbers) are related, and (ii) crinoids (sea lilies) are the sister taxon to extant eleutherozoan classes (asteroids, ophiuroids, echinoids, and holothuroids). However, the relat...

Despite widespread interest in the interplay between evolutionary and developmental processes, we still know relatively little about the evolutionary history of larval development. Many clades exhibit multiple shifts from planktotrophic (feeding) to non-planktotrophic (non-feeding) larval development. An important question is whether these switches are scattered randomly through geological hist...

Bioerosion is the destruction of hard substrates resulting from biological activity, and plays a relevant role in ecological interactions coastal dynamics processes. Several organisms have evolved structures behaviors allowing them to perforate biotic abiotic surfaces, transforming surfaces into particles, contributing significantly sediment production marine environment. Due large geographical...

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....