Satomi's Pygmy Seahorse

Extremely small size (height 11 mm, standard length 14 mm); 12 trunk rings; 27–28 tail rings; reduced ossification of inferior and ventral trunk ridges; 13 dorsal fin rays; 9 pectoral fin rays; small or absent anal fin; brooding area in males anterior to anus; well–developed spine on snout between eyes; distinct raised coronet with laterally expanded anterior and posterior flanges ('H–shaped' when viewed from above); snout without a bulbous tip; single gill opening on midline directly behind coronet supported by raised cleithral bone; large spines above eyes (double), laterally on head, on shoulder (cleithral) ring, bordering throat, and on superior trunk ridge (especially well–developed on TrR1–2,5,8 and 12 and TaR4,8,11,14); spines also present on lateral and ventral angles between trunk ridges and rings; spines on superior ridge of first and second trunk rings appear externally as if they are fused (Ref. 79848).Description: Characterized by white to pale brown color with black spot immediately anterior to eye; operculum, body and tail with blotchy red markings (Ref. 90102).

Male carries the eggs in a brood pouch (Ref. 205).

Dorsal soft rays (total): 13

Hippocampus satomiae congregates at night in groups of 3–5 individuals on small seafans, at depths of 15–20 m depth on the bottom below reef overhangs. During the day H. satomiae are difficult to find, even in areas where they are known to occur. At dawn individuals become active. At birth, the young are jet–black, about 3 mm in height and shaped similarly to the adults. They settle on the bottom near to their place of birth (Onishi, pers. comm.). The holotype, collected in October, was pregnant and carrying approximately eight young (Ref. 79848).

Satomi's pygmy seahorse (Hippocampus satomiae) is the smallest known seahorse in the world with an average length of 13.8 millimetres (0.54 in) and an approximate height of 11.5 millimetres (0.45 in).

This member of the family Syngnathidae is found at the Derawan Islands off Kalimantan. This species name, H. satomiae, is in honour of Satomi Onishi, the dive guide who collected the type specimens.

Hippocampus satomiae was selected as one of "The Top 10 New Species" described in 2009 by The International Institute for Species Exploration at Arizona State University and an international committee of taxonomists. The specific name honours Miss Satomi Onishi, a dive guide, who collected the type specimens.

Hippocampus satomiae attached to a coral