Zoological Studies

Temperature Effects on the Egg Development Time and Hatching Success of Three Acartia Species (Copepoda: Calanoida) from the Strait of Malacca

Teruaki Yoshida, Ching-Fong Liong, Abdul Mohamed Majid, Tatsuki Toda, and Bin Haji Ross Othman (2012) Development times and hatching success rates at 6 temperatures (10, 14, 18, 22, 27, and 31°C) are presented for eggs of 3 congeneric Acartiid copepods, Acartia spinicauda, A. erythraea, and A. pacifica, from the Strait of Malacca, Malaysia.  Egg development times of the 3 species were significantly related to the incubation temperature and each fit Bělehrádek’s function.  Hatching success at 10°C was the lowest (13%) and significantly differed from those at other temperatures (by an ANOVA).  Average hatching success rates at 14-31°C were 61% ± 26%, 78% ± 8%, and 87% ± 8% for A. erythraea, A. pacifica, and A. spinicauda, respectively.  The temperature functions for egg development times of A. erythraea, A. pacifica, and A. spinicauda were D = 294(T - 4.47)^-2.05, D = 545(T - 1.94)^-2.05, and D = 352(T - 4.30)^-2.05, respectively.  Values of the ‘biological zero’ for Acartia were significantly correlated with environmental temperatures, suggesting that differences in temperature adaptation of development rates of eggs can be described from a single parameter of the temperature response.  The results observed in this study were compared to findings from previous studies performed on other Acartiid species and from other copepod genera.