New Guinea Viviparous Brotula, Diancistrus novaeguineae (Machida 1996)

A New Guinea Viviparous Brotula, Diancistrus novaeguineae, Cenderawasih Bay, West Papua, Indonesia. Source: Gerald R. Allen / FishBase. License: All rights reserved


A small secretive yellowish to brown brotula that shelters in reef crevices on shallow coral reefs.

Like all bythitids, Diancistrus novaeguineae has internal fertilisation and females give birth to live young. Males have a copulatory organ with a penis and pseudoclaspers (bony lobes or prongs found in the tip of the penis). The form of the male pseudoclaspers is the most important character in distinguishing species of the genus Diancistrus. The outer pseudoclasper is slender and hook-shaped, and the inner pseudoclasper is stout, with broad fleshy appendix.

Juveniles and females are very difficult to identify. Other useful characters include head squamation, head pores, otoliths, morphometric proportions, and fin ray and vertebral counts.

Cite this page as:
Dianne J. Bray, Diancistrus novaeguineae in Fishes of Australia, accessed 30 Nov 2023,

New Guinea Viviparous Brotula, Diancistrus novaeguineae (Machida 1996)

More Info


Inhabits tropical waters of the southwestern Pacific and southeastern Indian Oceans: Indonesia, Papua New Guinea, the Solomon Islands and Vanuatu. Known in Australian waters from northwestern Western Australia, and the northern Great Barrier Reef, Queensland.

Shelters in caves and crevices on shallow coral reefs. Although rarely seen, the species is reportedly relatively common on the Great Barrier Reef north of 16°S and in Papua New Guinea south of 5°S.


Dorsal fin 74-85 (usually more than 77); Anal fin 60-69; Pectoral fin 17-21; Vertebrae 11 + 32-34=43-45; Gill rakers on anterior gill arch 13-17; Pseudobranchial filaments 2-3; D/V = anterior dorsal fin ray above vertebra number 6-7 (rarely 7); D/A = anterior anal fin ray below dorsal fin ray number 18-23; V/A = anterior anal fin ray below vertebrae number 13-14.

Body long, relatively slender, head profile moderately slender; eye large (2.1–3.4% SL); upper cheek scale patch with 7–9 scale rows, many scales on operculum above opercular spine (7–16 scales in 2–4 rows), an additional scale patch below opercular spine (4–12) in very large specimens.

Male pseudoclasper: outer pseudoclasper slender, hook-shaped with a rounded tip; inner pseudoclasper stout, with a broad fleshy appendage.


To about 105 mm SL.


Yellowish to brown in colour.


Little is known of the biology or life history of this species. Diancistrus novaeguineae is nocturnal and individuals are rarely seen as they hide in crevices and holes on coral reefs during the day.

Like all members of the family Bythitidae, fertilisation is internal, and females give birth to live young. The young are born at 10-15 mm SL, and individuals mature at about 35-40 mm SL. Males have a copulatory structure that consists of a penis with pseudoclaspers.


Although not popular due to its drab colour, this species is occasionally traded in the aquarium industry.

Similar Species

Diancistrus novaeguineae belongs to a large group of Diancistrus species with hook-like or stick-shaped outer pseudoclaspers. 

Species Citation

Parabrosmolus novaeguineae, Machida 1996, Ichthyol. Res. 43(2): 148, figs 1-4. Type locality: Bay on Krankett Island, Madang harbor, Madang, Papua New Guinea, depth 5-25 m.


Dianne J. Bray


Atlas of Living Australia

New Guinea Viviparous Brotula, Diancistrus novaeguineae (Machida 1996)


Allen, G.R. & Erdmann, M.V. 2012. Reef fishes of the East Indies. Perth : Tropical Reef Research 3 vols, 1260 pp.

Machida, Y. 1996. Parabrosmolus novaeguineae, a new genus and species of the subfamily Brosmophycinae from Papua New Guinea (Bythitidae, Ophidiiformes). Ichthyological Research 42(2): 147-151.

Møller, P.R. & Nielsen, J.G. 2010. Diancistrus novaeguineae. The IUCN Red List of Threatened Species. Version 2015.2. . Downloaded on 28 August 2015.

Nielsen, J.G., Cohen, D.M., Markle, D.F. & Robins, C.R. 1999. Ophidiiform Fishes of the World. An annotated and illustrated catalogue of pearlfishes, cusk-eels, brotulas and other ophidiiform species known to date. FAO Fisheries Synopsis No. 125 Vol. 18. 178 pp. (as Parabrosmolus novaeguineae)

Nielsen. J.G. 1999. Families Carapidae, Ophidiidae, Bythitidae, Aphionidae. pp. 1978-1985 in Carpenter, K.E. & Niem, V.H. (eds). The Living Marine Resources of the Western Central Pacific. FAO Species Identification Guide for Fisheries Purposes. Rome : FAO Vol. 3 1397-2068 pp. (as Parabrosmolus novaeguineae)

Schwarzhans, W., Møller, P.R. & Nielsen, J.G. 2005. Review of the Dinematichthyini (Teleostei: Bythitidae) of the Indo-West Pacific. Part I. Diancistrus and two new genera with 26 new species. The Beagle, Records of the Museums and Art Galleries of the Northern Territory 21: 73-163.

Quick Facts

CAAB Code:37228094

Biology:Live bearer

Conservation:IUCN Least Concern

Depth:2-25 m

Habitat:Reef associated

Max Size:11.6 cm TL

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