The gametogenic cycle and spawning of the short-necked clam, Paphia undulata Born, 1778 (Bivalvia: Veneridae) from Timsah Lake, Suez Canal, Egypt

Abstract

Background Paphia undulata, The Short-Necked Clam, is an edible marine bivalve that is consumed internationally and locally in Egypt. Overfishing and pollution have caused population declines in Egyptian fisheries during the last decade. Accurate reproductive biology knowledge is critical for designing long-term exploitation strategy for this resource. P. undulata spawning and gametogenic cycle research were carried out from January to December 2020 along Timsah Lake, Suez Canal, Egypt. Results These clams are functionally dioecious with a very low incidence of hermaphroditism. The sex ratio of the clam population was 1.0:1.07:0.04 for male, female and hermaphrodite respectively. The shell lengths of the collected clams were 4.64 ± 0.83 cm in males, 4.55 ± 0.9 cm in females and 4.19 ± 0.3 cm in hermaphrodite clams. The sizes at the onset of sexual maturity in both males and females were 2.1 cm and 2.5 cm respectively. Conclusions Reproductive studies revealed that this species has a prolonged spawning season that is not restricted to a specific period.