The Echinoid Directory

Lissocidaris Mortensen, 1939, p. 11

Diagnostic Features
  • Test relatively thick.
  • Apical disc about 40% the test diameter. Ocular plates just insert. Plates uniformly covered in dense granules. All five genital plates similar in size.
  • Interambulacrum with 7-9 plates in a series. Primary tubercles perforate, non-crenulate to faintly crenulate, especially on adapical side of ambital and adapical tubercles. Areoles circular and incised; scrobicular circles separated.
  • Scrobicular tubercles differentiated. Extrascrobicular areas not extensive; densely and uniformly covered in secondary tubercles.
  • No sutural furrows or pits.
  • Ambulacra weakly sinuous. Pore-pairs sub-conjugate with narrow interporal partition; pore zones sunken. Perradial zone with marginal series of contiguous primary tubercles and inner series of smaller tubercles.
  • Peristome similar in size to the apical disc. Ambulacral plates uniserial; interambulacral series extending to the mouth.
  • Primary spines long, cylindrical, with short collar and neck and small crown; shaft faintly ribbed with cortical hairs. Secondary spines adpressed.
Recent, Indian Ocean.
Name gender feminine
Lissocidaris fusca Mortensen, 1939, p. 11, by original designation.
Species Included
  • L. fusca Mortensen, 1939; Recent, Maldives, Indian Ocean
  • L. xanthe Coppard & van Noordenburg, 2007; Recent, Philippines
Classification and/or Status

Cidaroida, Cidaridae, Cidarinae.

Genus of Cidarinae


Distinguished from Calocidaris by having denser coalesced cortical hairs forming a smooth surface to its primary spines.  Its ambulacral spines are also more adpressed and it has two distinct forms of tridentate pedicellaria.  See Coppard & van Noordenburg (2007) for a full discussion of this genus.

Coppard, S. E. & van Noordenburg, H. 2007. A new species of Lissocidaris (Echinodermatat: Echinoidea: Cidaridae) from the Philippines: convergent evolution among smooth-spined cidaroids. Zootaxa 1493, 53-65.

Mortensen, T. 1928. A monograph of the Echinoidea. 1, Cidaroidea. C. A. Reitzel, Copenhagen.