noun
whitetip reef shark
Refers specifically to Triaenodon obesus, a common reef shark with white-tipped dorsal and tail fins.
ダイビング中にネムリブカを見かけた。
I spotted a whitetip reef shark while diving.
Compound of 眠り (nemuri, 'sleep') + 鱶 (fuka, 'shark'), likely from its habit of resting on the sea floor during the day. The exact origin is uncertain.