This study provides the first comprehensive information on the parasite fauna of the white-streaked grouper Epinephelus ongus. A total of 35 specimens from the archipelago Karimunjawa, Java Sea, Indonesia were studied for metazoan parasites. For comparison, the documented parasite community of 521 E. areolatus, E. coioides and E. fuscoguttatus from previous studies were analysed. A total of 17 different parasite taxa were recognized for E. ongus, including 14 new host and four new locality records. This increases the known parasite taxa of E. ongus by more than 80%. The ectoparasite fauna was predominated by the monogenean Pseudorhabdosynochus quadratus resulting in a low Shannon index of species diversity of the entire parasite community (0.17). By contrast, the species diversity excluding the ectoparasites reached the highest value recorded for Indonesian epinephelids (1.93). The endoparasite fauna was predominated by generalists, which are already known from Indonesia. This demonstrates the potential risk of parasite transmission through E. ongus into mariculture and vice versa. One-way analyses of similarity revealed a significantly different parasite community pattern of E. ongus compared with E. areolatus and E. fuscoguttatus as well as minor differences with E. coioides. This finding refers to different habitat preferences of these epinephelids within the analysed size range.

The grouper Cephalopholis taeniops is a carnivorous fish of the Cape Verde coastal marine ecosystem. Nothing is known regarding the age and growth of this epinephelid. In this study, the age and growth of C. taeniops was investigated by annual growth increment counts from 2804 specimens (7–51 cm total length) collected between January 2005 and December 2011. Whole otoliths underestimated the age indicated in sections by approximately 70%; therefore, sectioned otoliths were used in this study. A year's growth was represented by one opaque and one translucent ring. There was no apparent time lag from the start of the increase in the seawater temperature and the beginning of the formation of the opaque ring. The formation of the translucent rings coincided with a decrease in surface seawater temperature. Cephalopholis taeniops is a slow-growing and long-lived species, with ages of up to 20 years recorded. The seasonalized von Bertalanffy growth function was the best fitted among the four models tested, with an Akaike weight higher than 0.99. Growth was described by the seasonalized von Bertalanffy growth function as follows: L∞ = 54.26 cm, k = 0.135 year−1, t0 = −0.853 year, C = 0.439 and ts = 0.667.