China; Federated States of Micronesia; France (New Caledonia, Réunion, and Tahiti); India; Indonesia; Japan; Malaysia; Mauritius; Papua New Guinea; Philippines; Samoa; South Africa; Tonga; United Republic of Tanzania; United States of America of America (Hawaii); Viet Nam
Typically found >6 m depth; maximum reported depth 20 m; seagrass bed, weedy rocky reefs, sponges; soft bottom with soft corals and sponges
Maximum recorded adult height: 17 cm
Indian populations were moved under Schedule-I of the Wildlife Protection Act (1972) in 2001 which bans any collection or trade; H. histrix is listed as Vulnerable in the Viet Nam National Red Data Book
Data Deficient (DD)
The name H. histrix has been used indiscriminately for at least five species of spiny seahorse in the Indo-Pacific basin. The true H. histrix is a distinctive species with one of the largest distributions of any seahorse.