Shaggy Pipefish, Hypselognathus horridus Dawson & Glover 1982

Endemic temperate species, known only from 8 specimens trawled in a small region of the eastern part of the Great Australian Bight, South Australia, from Anxious Bay, westwards to Ceduna area 133^o30’S); demersal on the continental shelf at depths of 40–55 m. Nothing is known of the habitat of the Shaggy Pipefish.

Meristic features: Dorsal fin 29–32; Anal fin 3; Pectoral fin 10–13; Caudal fin 10; Trunk rings 27–28; tail rings 42–45; Subdorsal rings 7.00–6.00 + 4.00–5.50 = 11.00–11.75.

Body very slender and elongate; trunk shallow; head aligned with body; body posterior to dorsal fin markedly longer than that before dorsal fin; body and head surfaces, excluding membranes, clearly spinulose; no wart-like scutella on body rings; long snout, length 55–67% HL; snout depth 17–23% snout length; opercle without distinct longitudinal ridge in subadults or adults; tail not prehensile.

Single dorsal fin centred on back with base of moderate length; anal fin tiny, below front half of dorsal fin; caudal fin small, broadly pointed; pectoral fins small.

Maximum length about 300mm. The largest known specimen measures 280mm SL.

In preservative – overall greyish, peppered with minute brown or black spots; ring margins edged with black. Colour in life unknown.

Unknown, likely to feed on small crustaceans.

Males brood the eggs in a pouch under the tail. The pouch has protective pouch plates and membranous folds, with an everted pouch closure. The brood pouch is developed in a male of 154mm SL, suggesting that males are brooding by this size. Brood pouches of three males examined contained 20, 60 and 80 eggs.

The larvae are undescribed. The closely related species, Hypselognathus rostratus, has a long pelagic stage, with some planktonic individuals measuring up to 150mm.

Although of no interest to fisheries or aquaculture,  individuals have been taken as bycatch in bottom trawls.

Australian Commonwealth legislation: Marine listed under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act).

State Legislation: Listed as protected under the Fisheries (General) Variation Regulations 2006 of the South Australian Fisheries Act.

Hyselognathus horridus differes from H. rostratus in having spines on head and body surfaces at all sizes, versus having rounded, wart-like scutella on each body ring in larger juveniles and adults. H. horridus has a greater number of trunk and tail rings (27 and 42–45 versus 25 and 41–44), fewer pectoral fin rays (10–12 versus 12–14), and a deeper snout.

Hypselognathus is from the Greek hypselos (high) and gnathos (jaw). The specific name horridus is from the Latin meaning bristly or rough, in reference to the spines on the head and body.

Hypselognathus horridus Dawson & Glover 1982, Proc. Biol. Soc. Wash. 95(2): 403, figs. 1-2, off Anxious Bay, Great Australian Bight, South Australia, depth 30 fms.

Dianne J. Bray & Vanessa J. Thompson