Spiny Pipehorse, Solegnathus spinosissimus Günther 1870

Off Caloundra, southern Queensland, to south of Cape Otway, Victoria, including around Tasmania. Elsewhere the species occurs in New Zealand. 

Inhabits muddy, silty, shelly and rubble substrates, and rocky reefs, and may be washed ashore during storms. In the southern part of their range, Spiny pipehorses are found in relatively shallow waters, and are occasionally seen by divers in the Derwent Estuary (Tasmania).

Dorsal fin 34-42; Pectoral fin 23-26; trunk rings 24-27; tail rings 51-59; total rings 76-84; total subdorsal rings 8.75-11.75.

Superior trunk ridge not confluent with superior tail ridge, opercular membrane with bony platelets on sides and ventral surface; body surfaces spinulose; snout shallow, depth more than 5.5 in snout length; dorsal surface of trunk and anterior part of tail flat to a little convex; body surfaces spinulose, spines very dense in smaller specimens.

This is the largest member of the family family Synganthidae in Australia, attaining a maximum length of 49 cm.

Overall pink, red or orange with about 7 darker bars, blotches or bilateral pairs of spots dorsally on the trunk; sides of trunk with numerous narrow, yellow, vertical bars continuing onto the tail as blotches or spots; ventral midline bright red; reddish brown blotch around the anus.

Individuals use their prehensile tail to cling to macroalgae or sessile invertebrates, and feed on planktonic invertebrates drifting by in the currents.

Like all members of the family Syngnathidae, Spiny Pipehorse males incubate the eggs. Solegnathus species lack a brood pouch, and females deposit their eggs onto a specialised brood area under the tail of the male pipehorse. The brood area becomes spongy and highly vascularised during the breeding season and the eggs become embedded in this vascularised tissue.
Males just over 20cm in length may be brooding eggs, although most do not brood until they are at least 30cm. The eggs are incubated by the male until they hatch, and newly hatched Spiny Pipehorses are reported to be benthic and lack a pelagic life stage. In specimens examined, the brood size ranged between about 60 and 200 eggs.

Taken as incidental bycatch in dredges, trawls, seines and in crayfish pots. Individuals taken as bycatch in Australia’s Southeast Trawl Fishery (SEFT) may be dried and sold to the Traditional Medicine Industry (TCM) in Australia and possibly overseas (subject to rules and regulations set down by the Australian Fisheries Management Authority (AFMA), the EPBC Act and the Commonwealth Wildlife Protection (Regulation of Exports and Imports) Act 1982.

Dried Solegnathus specimens are used in the preparation of medicines and as aphrodisiacs in the Chinese Traditional Medicine Industry (TCM). Pipehorses are thought to be of high medicinal value in TCM, being similar in medicinal value to seahorses.

IUCN Red List of Threatened Species: Data Defficient on the 2010 IUCN Red List of Endangered Species.

Marine listed under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). Solegnathus spinosissimus is subject to the export controls of the Commonwealth Wildlife Protection (Regulation of Exports and Imports) Act 1982

Listed as protected under the New South Wales, Victorian and Tasmanian Fisheries Management Acts.

Although Kuiter (2009) considered New Zealand records of this species to represent a different species, Solegnathus naso Whitley 1941, Stewart (2015) suggested additional information was needed and retained the name S. spinosissimus for the New Zealand population.

Solegnathus spinosissimus differs from all other members of the genus Solegnathus except S. robustus, in having lateral and ventral platelets on the opercular membrane, a truncate spine under the pectoral fin, ridged scutella and spinulose body surfaces. The species differs from S. robustus in having a more slender snout (snout depth in snout length 5.6-10.1 vs 3.7-4.5). S. spinosissimus also lacks short supplemental ridges on the body surface, lacks a strongly convex dorsal surface, and the anterior part of the tail is not oval in cross-section, characters with distinguish S. robustus.

Solenognathus spinosissimus Günther 1870 Cat. Fish. Brit. Mus. 8: 195. Type locality: Tasmania.

Bray, D.J. 2022

Atlas of Living Australia