Thursday 21 August 2025, 10.30am (SAST)
Zoom Registration link:
https://zoom.us/meeting/register/MzAlJA8qRWS-cR1AaBtjbw
Passcode: 035119
by Hesmarié Botha
Research Student, NRF-SAIAB
From the last meal to first breath: Developmental insights into the temporary parasitic isopod, Gnathia pantherina Smit & Basson, 2002.
Gnathiid isopods are small marine parasites that temporarily attach to fish for feeding. Although new species are discovered yearly, little is known about which fish they target or how they grow and reproduce. Along the southern African coast, only four of the nine known species have recorded hosts, and just two have published life cycles. In this study, 222 late-stage Gnathia pantherina larvae were collected in April 2025 from a newly recorded host, the brown shyshark, at Boknesstrand.
They were kept in artificial seawater at 20–21 °C until they matured and reproduced. On average, males became adults after 25 days, while females released young after 54 days. This is the first study to document the partial life cycle for this species (from P3 to Z1) and estimate its development timeline, providing a useful insight for future research on gnathiids in the region.
