Description: (based on 22 specimens): Adult height: 15.0-25.0cm. Rings: 11+40 (39-41). Snout length: 2.1 (2.0-2.3) in head length. Dorsal fin rays: 18 (17-19) covering 2+1 rings. Pectoral fin rays: 18 (17-19). Coronet: high, with five short spines, and high plate in front of coronet. Spines: low and rounded, slightly better developed in younger specimens, but still blunt-tipped. Other distinctive characters: long, slightly backwards pointing, rounded cheek spine; deep head; narrow body; thick body rings; prominent, rounded eye spine; thick snout. Color pattern: pale, often with tiny white spots running in vertical lines, but otherwise uniform in color. Young H. kelloggi look very similar to H. spinosissimus.