(Lampert, 1885)
M. intercedens is a blue-black sea cucumber with bright red ambulacra. It is a small (< 75 (115) mm), cylindrical species, tapering at both ends, with 30 tentacles. Tube feet are concentrated along ambulacra. The body is thin and pliable, the tegument smooth. Spicules are tables with a high spinous spire and a pillar with two bridges; the disc is formed with four large and four small holes (M. intercedens spicules[/l], [l]m_intercedens_spicules_2.jpgM. intercedens spicules 2[/l]) M. intercedens is a [l][m]Glossary[/m][r]Coast[/r]coastal species, found on intertidal flats-in "U-shaped" burrows or entwined in rhizomes of seagrasses.