The megamouth shark, Megachasma pelagios, is not a luminous species. PLoS ONE, 15(11), Article e0242196
DOI: 10.1371/journal.pone.0242196
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Etmopterus spinax, the velvet belly lanternshark, does not use bacterial luminescence. Acta Histochemica, 121(4), 516–521
DOI: 10.1016/j.acthis.2019.04.010