Dalhousie Catfish, Neosilurus gloveri Allen & Feinberg 1998

Occurs in a small subset of mound springs in the Dalhousie Mound Springs Complex, Witjira National Park, in the arid zone of northern South Australia. Although individual springs are isolated, all springs in the complex have a common groundwater source - the Great Artesian Basin. When it was described in 1998, the species was only known from the Main Spring at Dalhousie Springs and Nilpinna Spring in the northern part of South Australia. The species was abundant in the spring in water temperatures between 33.5-38.3 deg C.

The Dalhousie Catfish is nocturnal and swims near the bottom of these warm, artesian spring-fed pools and their outlet streams.

Dorsal fin I, 4-5; Caudal/Dorsal/Anal rays 53; Pectoral fin I, 7-9; Pelvic fin 9-11; Gill rakers 14-16; Vertebrae 38-42; Branchiostegal rays 7-8.

Body elongate, tapering posteriorly; body depth 14-19 % SL; head moderately flattened dorsoventrally; head length 20-25% SL; dorsal profile of head nearly straight; snout pointed in lateral view, snout length 35-42 % HL; mouth subterminal; lips fleshy but relatively thin; anterior nostril tubular, on upper lip; posterior nostril narrow slit behind nasal barbel; eyes relatively small, eye diameter 15-21 % HL; nasal barbel reaching slightly beyond level of eye, nasal barbel length 40-60% HL; maxillary and outer mental barbels reaching to about edge of preoperculum; inner mental barbel slightly shorter; slender conical teeth in several rows on upper and lower jaws, patch of larger conical teeth on palate; branchiostegal rays 6-8.

First dorsal fin relatively short, its tip pointed, originating in front of level of pelvic fins; pectoral fins inserted just behind opercular margin, tips rounded; caudodorsal fin originating far back towards end of body; base of caudodorsal fin 18-25% SL.

12 cm TL.

Dark chocolate brown to greyish above, lighter below and on fins.

Omnivore - nocturnally active fishes that feed on active aquatic invertebrates (e.g. ostracods), terrestrial insects, small fishes such as hardyheads, and benthic prey such as gastropods molluscs, along with some plant material.

The sexes are separate and fertilisation is external. Females reach sexual maturity at 44 mm SL, and spawn small (~ 1mm), non-adhesive eggs that are likely to be scattered over the substrate.

Glover (1989) reported that a 72 mm TL female contained 136 eggs, and a 120 mm TL female carried 1197 eggs. It is not known if spawning is seasonal or occurs all year round.

IUCN Red List Status: Critically Endangered

Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act): Critically Endangered

Tolerates salinity to 10 p.p.t. and temperatures between 16° and 44°C, but usually remains in water between 30° and 38°C.

Differs from other species in its very small size and some meristic features.

Neosilurus is from the Greek neos meaning "new", and silouros meaning "catfish". The species is named after the late John Glover, former Curator of Fishes at the South Australian Museum.

Neosilurus gloveri Allen & Feinberg 1998, aqua, Journal of Ichthyology and Aquatic Biology 3(1): 13, fig.1. Type locality: Main Spring, Dalhousie Springs, South Australia, about 26°25'S, 135°30'E.

Gomon, M.F. & Bray, D.J. 2024

Atlas of Living Australia