Abactinal plate of each arm contains granules and blunted small spines and pedicellariae
. Tube feet were relatively small and embedded inside the adambulacral groove.
Keywords: Diadematidae, pedicellariae, sea urchins, Brazil, taxonomy.
ascensionis and discuss the importance of the pedicellariae for the correct identification of the species.
For the correct identification of specimens, the morphologies of the naked test, of the pedicellariae, and of the spines were observed (Mortensen, 1909; Tommasi, 1966; Coppard and Campbell, 2004; 2006a, b).
In larvae, day 20 coincides with the first appearance of the rudiment stage and day 24 coincides with the first appearance of pedicellariae. From this stage to metamorphosis, the increase in protein content was 3 fold, and the increase in carbohydrates was 5 fold (Table 2).
Development of Lytechinus variegatus in this work was much slower than reported by McEdward and Herrera (1999), who obtained full development of the rudiment and pedicellariae by days 8-9 at a higher temperature of 26[degrees]C and a richer diet either of 8,000 cells [ml.sup.-1] of Rhodomonas (8 days) or 8,000 cells [ml.sup.-1] Dunaliella (9 days).
First appearance of pedicellariae >30 Juvenile at 0.371 [+ or -] 0.135 metamorphosis Age Carbohydrate (Days) 1 0.022 [+ or -] 0.013 6 0.017 [+ or -] 0.011 10 0.041 [+ or -] 0.015 13 0.049 [+ or -] 0.011 17 0.077 [+ or -] 0.039 20 0.078 [+ or -] 0.027 24 0.148 [+ or -] 0.070 >30 0.764 [+ or -] 0.201 TABLE 3.
This individual also lacked pedicellariae. These two unusual larvae suggest a developmental link between the asymmetry of the larval arms and the formation of the juvenile rudiment.
They had 5 primary podia, some short juvenile spines projecting in pairs from the aboral surface near the podia, and pedicellariae retained from the larval body (Fig.
Responses to these stimuli range from local reflex reactions in the spines, pedicellariae, a nd tube feet to fully coordinated responses in which the whole organism moves toward or away from a stimulus source.
Observations on the activity of echinoid pedicellariae: II.
Integumentary resorption and collagen synthesis during regression of headless pedicellariae
in Sphaerechinus granularis (Echinodermata, Echinoidea).