The Collar Seahorse was described in 2001. It is only known from Lord Howe Island.
The author of the species, Rudie Kuiter wrote "The species has two more trunk rings than most seahorses and the spines on the head are usually double, almost V-like from the base. Colour is probably reddish and it may live in the red algae patches at moderate depths. In clear water algae is still common at 100 m."
Only two specimens have been collected. The holotype (AMS IA.2424) was found washed up on a beach at Lord Howe Island in 1925, and the fish in the image was recovered while still alive from the gut of a kingfish at Lord Howe Island.
The species is only known from the waters of Lord Howe Island, New South Wales.
- Hoese, D.F., Bray, D.J., Paxton, J.R. & G.R. Allen. 2006. Fishes. In Beesley, P.L. & A. Wells. (eds) Zoological Catalogue of Australia. Volume 35. ABRS & CSIRO Publishing: Australia. parts 1-3, pages 1-2178.
- Kuiter, R.H. 2009. Seahorses and their relatives. Aquatic Photographics. Pp. 333.