Fecundity, egg Volume, and reproductive output of Xestoleberis rotunda (Podocopida: Ostracoda) from the Red Sea, Egypt

In this work, we evaluated the sex ratio, fecundity, egg volume, and reproductive output of the marine ostracod species Xestoleberis rotunda in the Red Sea, Egypt. The sex ratio was biased towards females (2.2: 1). The ovigerous and non-ovigerous females represent 41.8 and 58.2%, respectively. The brood pouch of X. rotunda contains vitellogenic stages, mature eggs, first instars, and second instars simultaneously. The highest reproductive activity was in the summer season, with the warmest temperatures. Fecundity ranged from 25 to 48 eggs in ovigerous females, and the relationship between egg number and carapace length was positive. Temperature correlated positively with the number of males, ovigerous females, and non-ovigerous females. Also, the number of males and ovigerous females correlated positively with electrical conductivity. Conversely, there is a negative correlation between pH and the number of ovigerous and non-ovigerous females. Furthermore, the number of males correlated negatively with salinity and correlated positively with dissolved oxygen. The reproductive output of the different developmental stages ranged from 0.0134 to 19.15%, which can elevate reproductive success.