However, its outer surface (below), with defensive spines, tube feet and pedicellariae
grippers, has two kinds of light-detecting opsin proteins.
Five specimens were collected and transported to the laboratory where morphological studies of the test and pedicellariae
5 h Eight-cell embryos 9 h 16-cell embryos 23 h Unhatched blastulae; wrinkled with a clear blastocoel and irregular blastoderm 47 h * Hatched blastulae; apical tuft visible 73 h Initiation of gastrulation 4 days Mid-stage gastrulae; archenteron about 1/2 way into blastocoel 7 days Gastrulae that are compressed; first spicules visible with cross-polarized light 8 days Prisms 14 days Two-arm plutei with open mouths 33 days Four and six-arm plutei 48 days Formation of lobes begins 79 days Juvenile rudiments with podial buds and pedicellariae
120 days Metamorphosis; juvenile spine count ranges from 5 to 23 * Blastulae were unhatched at 23 and 33 h.
2002), probably through the "spine system," the tube feet and the pedicellariae
(Smith et al.
Some ossicles are rod-shaped to make protruding appendages such as spines, pedicellariae
, and paxillae.
With the high concentration diet, protein and carbohydrate content per larvae remained relatively constant through day 17 after fertilization, through the 8-arm stage, and then significantly increased by day 20 coinciding with the first appearance of the rudiment stage, remaining high by day 24, coinciding with the first appearance of pedicellariae
Regeneration of spines and pedicellariae
in echinoderms: a review.
The other pedicellariae
were located on the dorsal and ventral surfaces of the larval body near the bases of the postoral and posterodorsal arms.
A suite of five representative members of these protein families is almost exclusively expressed in the early larva and in the tube foot and pedicellariae
of the adult animal.
forbesi, and the long slender abactinal spines with a wreath of minor pedicellariae
halfway up these spines typical of A.
They are, however, able to counter predation by structural and behavioral means such as the use of spines and globiferous pedicellariae
, which are minute, forcep-like appendages that can seize and, in some cases, inject venom into the skin of predators (Campbell, 1983).
Integumentary resorption and collagen synthesis during regression of headless pedicellariae
in Sphaerechinus granularis (Echinodermata, Echinoidea).