Holsworth’s Grunter, Syncomistes holsworthi Shelley, Delaval & Le Feuvre 2017


Holsworth’s Grunter. Syncomistes holsworthi, from the Ord River, Kimberley region, Western Australia. Source: Matthew Le Feuvre & James Shelley, University of Melbourne / Museums Victoria. License: All rights reserved

Summary:
During the wet season, Holsworth’s Grunter is dark bluish-brown, becoming greyish to silver during the dry season. The species is darker above, becoming paler below.
Juveniles are whitish below, with a bluish-silvery stripe below the eye to the snout, a dark blotch on the gill cover, dark scale margins, and dark fins occasionally with a purple tinge. No stripes were observed on the sides of juveniles or adults.

Cite this page as:
Bray, D.J. 2020, Syncomistes holsworthi in Fishes of Australia, accessed 29 Mar 2024, https://fishesofaustralia.net.au/home/species/5402

Holsworth’s Grunter, Syncomistes holsworthi Shelley, Delaval & Le Feuvre 2017

More Info


Distribution

Occurs throughout the Ord, Penticost, and Durack rivers in the eastern Kimberley region, Western Australia, and the Victoria River, Northern Territory.
Adults prefer deeper, slow flowing sections of creeks and rivers, along with still waters and billabongs. Juveniles inhabit shallow, still waters or occasionally riffle habitats. The species has been found in clear and turbid waters, over rocky and muddy substrates, often where algae is abundant. Recorded in water temperatures up to 36°C. 
Individuals have been seen shoaling in the middle of the water column around snags, sometimes with the Lake Bonaparte Grunter, Syncomistes bonapartensis

Colour

Body dark bluish-brown overall during wet season, greyish to silver overall during dry season. Darker dorsally, becoming lighter along the ventral surface. Juveniles white on ventral surface. A bluish-silver stripe running below eye to snout. Opercle and subopercle with a dark blotch extending ventrally from opercular spine. Posterior scale margins have a dark band. All fins dark, occasionally with a purple tinge. No stripes were observed on the sides of juveniles or adults.

Feeding

Feeds mostly on filamentous algae and detritus scraped off rocks with specially modified teeth.

Biology

Individuals are sexually mature at 90–100 mm and spawning occurs during the wet season, following a major flood. The eggs are large (~3 mm) and non-adhesive. 

Etymology

The specific name holsworthi honours Bill Holsworth whose foundation financed the expedition on which this species was found, as well as providing ongoing support for doctoral research into the ecology, management and natural history of Australian wildlife.

Species Citation

Symcomistes holsworthi Shelley, Delaval & Le Feuvre 2017, Zootaxa 4367(1): Type locality: Flying Fox Creek, Ord River, Western Australia, 16°32'54.258''S, 128°22'13.31''E.

Author

Bray, D.J. 2020

Resources

Atlas of Living Australia

Holsworth’s Grunter, Syncomistes holsworthi Shelley, Delaval & Le Feuvre 2017

References


Buckle, D., Storey, A., Humphrey, C. & Chandler, L. 2010. Fish and macroinvertebrate assemblages of the upper Ord River catchment. Internal Report 559, January, Supervising Scientist, Darwin. 38 pp. (as Syncomistes rastellus)

Le Feuvre, M. C. 2017. Triple jeopardy in the tropics: assessing extinction risk in Australia's freshwater biodiversity hotspot. Ph.D. Thesis, School of Biosciences, University of Melbourne. http://hdl.handle.net/11343/194371

Le Feuvre, M.C. 2019. Syncomistes holsworthi. The IUCN Red List of Threatened Species 2019: e.T129056558A129056563. https://dx.doi.org/10.2305/IUCN.UK.2019-3.RLTS.T129056558A129056563.en. Downloaded on 01 September 2020.

Shelley, J.J. 2016. Evolution and biogeography of Australian tropical freshwater fishes. PhD Thesis. The University of Melbourne, Melbourne, VIC, 273 pp. http://hdl.handle.net/11343/120615 (as Syncomistes sp. 1)

Shelley, J.J., Delaval, A. & Le Feuvre, M.C. 2017. A revision of the grunter genus Syncomistes (Teleostei, Terapontidae, Syncomistes) with descriptions of seven new species from the Kimberley region, northwestern Australia. Zootaxa 4367(1): 1-103 http://dx.doi.org/10.11646/zootaxa.4367.1.1

Shelley, J.J., Gomon, M.F. & Le Feuvre, M.C. 2018. Family Terapontidae. pp. 118-158 in Shelley, J.J., Morgan, D.L., Hammer, M.P., Le Feuvre, M.C., Moore, G.I., Gomon, M.F., Allen, M.G. & Saunders, T. (eds) A field guide to the freshwater fishes of the Kimberley. Murdoch University, Murdoch, Western Australia, 262 pp.

Quick Facts


CAAB Code:37321039

Conservation:IUCN Least Concern

Habitat:Freshwater

Max Size:26 cm SL

Native:Endemic

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