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AQUACULTURE COMMITEE
IV (growing), stage V (premature), stage VI (mature), stage VII (partly spawned),
stage VIII (post spawned).
Results – As shown in Fig. 1A, the percentage of individuals with gonads in which
developing gametes were found (stages III to VIII, grey background patterns) was
more than 90% on April and never decreased until 50% also in summer, when a resting
period would be expected; on September the percentages of pre-mature and mature
individuals (V-VII) which had decreased on summer, increased again, being more than
70% on November. The Gonad Index (Fig. 1B) reflected the gonad conditions, being
higher on April and September, when gonad ascini were filled of both nutritive
phagocytes and mature gametes.
100%
80%
60%
40%
20%
0%
A
St-I St-II St- III St-IV
St-V St-VI St-VII St-VIII
April May July Sept Nov
0
B
41 st S.I.B.M. CONGRESS Rapallo (GE), 7-11 June 2010
248
14
12
10
8
6
4
2
April May July Sept Nov
Fig. 1 – Gonad reproductive condition (A) and Gonad Index (B) for each sampling time.
Stadio riproduttivo delle gonadi (A) ed indice gonadico (B) ai vari tempi di campionamento.
Conclusions – The populations of P. lividus in the Mediterranean area remain mature
all year, with a brief resting period (stages I-II) from July to September (Sánchez-
España et al., 2004), being able to “skip” the resting period in presence of high
availability of food (Byrne, 1990; Spirlet et al., 1998). The specimens here analyzed,
taken from the mid-to-low Adriatic, exhibit a similar reproductive pattern; the almost
continuous presence of individuals with an active gametogenesis and the ability of the
sea urchin gonads in quick responding to abrupt variations in the availability and
quality of food is of crucial importance in order to set up rearing protocols for a shortterm
induction of gonad yield and of gamete maturation in controlled conditions.
References
BYRNE M. (1990) - Annual reproductive cycles of the commercial sea urchin P. lividus from an
exposed intertidal and sheltered subtidal habitat on the west coast of Ireland. Mar. Biol., 104:
275-289.
GUIDETTI P., FRASCHETTI S., TERLIZZI A., BOERO F. (2003) - Distribution patterns of sea
urchins and barrens in shallow Mediterranean rocky reefs impacted by the illegal fishering of the
rock-boring mollusc Lithophaga lithophaga. Mar. Biol., 143: 1135-1142.
SÁNCHEZ-ESPAÑA A.I., MARTINEZ-PITA I., GARCÌA F.J. (2004) - Gonadal growth and
reproduction in the commercial sea urchin Paracentrotus lividus (Lamarck, 1816)
(Echinodermata: Echinoidea) from Southern Spain. Hydrobiologia, 519: 61-72.
SPIRLET C., GROSJEAN P., JANGOUX M. (1998) - Reproductive cycle of the echinoid
Paracentrotus lividus: analysis by means of the maturity index. Invert. Reprod. Develop., 34 (1):
69-81.
Research supported by MIUR (Decr. 09.10.02; grant n.143 to dott.ssa A. Fabbrocini).