Overfishing drives over one-third of all sharks and rays toward a global extinction crisis.

The scale and drivers of marine biodiversity loss are being revealed by the International Union for Conservation of Nature (IUCN) Red List assessment process. We present the first global reassessment of 1,199 species in Class Chondrichthyes-sharks, rays, and chimeras. The first global assessment (in 2014) concluded that one-quarter (24%) of species were threatened. Now, 391 (32.6%) species are threatened with extinction. When this percentage of threat is applied to Data Deficient species, more than one-third (37.5%) of chondrichthyans are estimated to be threatened, with much of this change resulting from new information. Three species are Critically Endangered (Possibly Extinct), representing possibly the first global marine fish extinctions due to overfishing. Consequently, the chondrichthyan extinction rate is potentially 25 extinctions per million species years, comparable to that of terrestrial vertebrates. Overfishing is the universal threat affecting all 391 threatened species and is the sole threat for 67.3% of species and interacts with three other threats for the remaining third: loss and degradation of habitat (31.2% of threatened species), climate change (10.2%), and pollution (6.9%). Species are disproportionately threatened in tropical and subtropical coastal waters. Science-based limits on fishing, effective marine protected areas, and approaches that reduce or eliminate fishing mortality are urgently needed to minimize mortality of threatened species and ensure sustainable catch and trade of others. Immediate action is essential to prevent further extinctions and protect the potential for food security and ecosystem functions provided by this iconic lineage of predators.

Glossanodon macrocephalus, a new argentine fish (Argentinidae) from the Arabian Sea.

A new species of argentinid fish, Glossanodon macrocephalus Bineesh Endo, from the Arabian Sea, off the southwestern coast of India, is described on the basis of four specimens (129-164 mm SL). The new species clearly differs from its congeners in the following combination of characters: dorsal-fin rays 10-11; pectoral-fin rays 21-23; anal-fin rays 12-13; pelvic-fin rays 11-12; branchiostegal rays 5; gill rakers on first arch 30-36; vertebrae 47-48; a patch of small conical teeth on middle of lower jaws; predorsal 49-51% SL; prepectoral 36-39% SL; prepelvic 57-58% SL; distance from pelvic to anal-fin origin 26-28% SL; head length 35-39% SL; eye diameter 22-26% HL; snout length 28-30% HL; location of anus immediately anterior to anal-fin origin; broad longitudinal black stripe above lateral line; dark spot on the base to half of pectoral fin; and no teeth on tongue. The new species is a benthopelagic dweller on muddy bottoms in depths of around 300-600 m.