Didymothallus nudigena Schwarzhans & Møller 2011


Illustration of the holotype and a paratype of Didymothallus nudigena, WAM P.27671-032, from a rockpool in the Lacepede Islands, Western Australia . Source: After Schwarzhans & Møller (2011) New Dinematichthyini (Teleostei: Bythitidae) from the Indo-west Pacific, with the description of a new genus and five new species. The Beagle, Records of the Museums and Art Galleries of the Northern Territory 27:161-177. License: All rights reserved

Summary:
A uniform dusky red to reddish-violet cusk-eel, lighter ventrally and darker dorsally, with paler translucent fins, and the head with only a few small, non-imbricate scales on upper part of the cheek.

Cite this page as:
Bray, D.J. 2019, Didymothallus nudigena in Fishes of Australia, accessed 30 Sep 2022, https://fishesofaustralia.net.au/home/species/4811

Didymothallus nudigena Schwarzhans & Møller 2011

More Info


Distribution

Fitzroy Reefs, north of Shark Bay, to off Broome, Western Australia. Inhabits inshore reefs and tide pools in depths to 5 m.

Features

Dorsal fin 78-90; Anal fin 57-69; Vertebrae 12+28-31=40-43. 
V in D 1.9-2.3; head with few small, non-imbricate scales on upper cheeks only; single (outer) pseudoclasper wing-shaped with two slender supporters, anterior supporter shorter than posterior one with small distal appendix on inner face, posterior supporter curved, hockey-stick shaped.

Colour

Body a uniform dusky red to reddish violet, lighter ventrally and darker dorsally. The vertical fins are similar in colour, but paler and translucent.

Biology

Viviparous - live bearer.

Similar Species

Didymothallus nudigena differs from Didymothallus mizolepis in having few small, non-imbricate scales on the upper cheek only (vs a continuous imbricate scale patch on upper and lower cheek), the pseudoclasper with the short anterior and hockey-stick bent posterior supporters (vs straight and almost equal in length), the curved penis (vs straight) and the lower V in D (1.9–2.3 vs 2.2–2.6).

D. nudigena differs from Didymothallucriniceps in having a higher number of dorsal fin rays (78–90 vs 69–77), a reduced scale patch on the upper cheek, and a hockey-stick shaped posterior supporter of the outer pseudoclasper.

Etymology

Didymothallus is from the Greek didymos (= double, twofold) and thallus (= branch) in plants, referring to the two supporters of nearly equal length in the single pair of pseudoclaspers. The specific name nudigena is from the Latin nudus (= naked) and gena (= cheek), in reference to the reduced squamation of the cheeks.

Species Citation

Didymothallus nudigena Schwarzhans & Møller 2011, The Beagle, Records of the Museums and Art Galleries of the Northern Territory 27: 164. Type locality: Lacepede Islands, Western Australia, rock pool at western tip [16°51'S, 122°05'E]. 

Author

Bray, D.J. 2019

Resources

Atlas of Living Australia

Didymothallus nudigena Schwarzhans & Møller 2011

References


Schwarzhans, W. & Møller, P.R. 2007. Review of the Dinematichthyini (Teleostei: Bythitidae) of the Indo-west Pacific. Part III. Beaglichthys, Brosmolus, Monothrix and eight new genera with description of 20 new species. The Beagle, Records of the Museums and Art Galleries of the Northern Territory 23: 29-110 (in part as Didymothallus mizolepis - some WA material)

Schwarzhans, W. & Møller, P.R. 2011. New Dinematichthyini (Teleostei: Bythitidae) from the Indo-west Pacific, with the description of a new genus and five new species. The Beagle, Records of the Museums and Art Galleries of the Northern Territory 27: 161-177.

Quick Facts


CAAB Code:37228113

Biology:Live-bearer

Depth:0-5 m

Habitat:Reef associated

Max Size:6.6 cm SL

Native:Endemic

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