The red handfish (Thymichthys politus) is a species of marine ray-finned fishes belonging to the family Brachionichthyidae, the handfishes. Like all members of the handfish family this fish is endemic to Australia. The IUCN classify the red handfish as Critically Endangered.
| Red handfish | |
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Scientific classification 
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| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Lophiiformes |
| Family: | Brachionichthyidae |
| Genus: | Thymichthys |
| Species: | T. politus
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| Binomial name | |
| Thymichthys politus (Richardson, 1844)
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| Synonyms | |
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Taxonomy
editThe red handfish was first formally described as Cheironectes politus in 1844 by the Scottish naval surgeon, Arctic explorer and naturalist John Richardson with its type locality given as the Acteon Islands off Tasmania.[2] The Australian zoologists Peter R, Last and Daniel C. Gledhill created the new genus Thymichthys they designated Cheironectes politus as the type species.[3] This genus is classified within the family Brachionichthyidae which the 5th edition of Fishes of the World classifies the family Brachionichthyidae within the suborder Antennarioidei within the order Lophiiformes, the anglerfishes.[4]
Etymology
editThe red handfish has the genus name Thymichthys which is a combination of thymos, meaning "warty growths", and ichthys, which means "fish". This is an allusion to the warty protuberances on the skin of this fish. The specific name, politus, means "polished", an allusion Richardson did not explain but it is thought to be to the smoothness of its skin to the touch or its bright colouration.[5]
Description
editThe red handfish is distinguished by its small, flattened wart-like protuberances that cover its body and red colouration. Two colour morphs exist, a bright red morph with red colour on both body and fins, with a black line separating the white fin edges and a mottled morph with pink body covered in many red patches, with translucent pink fins expressing some bright red patches. They measure an average standard length of 61.4 mm (2.4 in) and an average total length of 80.1 mm (3.2 in).[3] They use their hand-like fins to crawl rather than swim.[6]
Ecology and behavior
editDistribution and habitat
editHistorically, the species was found in multiple subpopulations in Tasmania, including Port Arthur, Fortescue Bay, the Actaeon Islands, D'Entrecasteaux Channel, and the Forestier Peninsula. Currently, the species has been found only on two small reefs in Frederick Henry Bay. These species typically reside in reef sand junctions, where there is an abundance of sand and rocks. The macro-algae that covers the rock allows them to easily blend in with their environment. These reefs measure no more than 50 m in diameter with a circular area of no more than 75 m. It is found at depth ranges from 1 m up to 20 m.[3]
Reproduction
editTheir limited range is attributed to the low reproduction and dispersal rate. Unlike other fish they recruit directly on the benthos.[7] Females lay their eggs at the base of seagrass from august through to October. Each egg mass contains 30- 60 eggs that are connected by tubules bound together. These eggs are then guarded by the adults until they hatch.[8]
Diet
editLittle is known about their diet but that it consists of animals that live in the benthos. Their diet consists of small crustaceans and polychaete worms.[9]
Conservation
editIn November 2023, researchers at Tasmania’s Institute for Marine and Antarctic Studies (IMAS) found a cluster of 21 yellow eggs in one of their tanks for red handfish. One of the researchers said “We’re delighted to announce the safe arrival of 21 baby red handfish.” This is the second time red handfish have been bred in captivity, with the previous time being in 2021.[10]
Threats
editGeneral threats to red handfish include small, very fragmented populations and local increases in density of native purple urchins. Native purple urchins overgraze the seaweed habitat required for shelter and spawning for the red handfish. Summer observations of low seaweed on urchin barrens suggest that loss of seaweed habitat might represent a key threat to long term viability of the population In addition, the close vicinity of urban development increases the risk of nutrient runoff, pollution, siltation, and turbidity. This results in habitat degradation through the ruin of the red handfish preferred seaweed habitat. Loss of spawning substrate limit the red handfish as to where their eggs can attach resulting in the eggs being lost to the current. Limitations include difficulty spotting the species among its habitat. Red handfish may face severe pressure due to direct environmental consequences of warming coastal waters, including potential implications on reproduction, egg development, feeding, and escape reaction, which are currently unknown.[1]
Status
editThe red handfish is classed as Critically Endangered under the Australian Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) and by the IUCN, and as Endangered under Tasmania's Threatened Species Protection Act 1995.[7]
References
edit- ^ a b Stuart-Smith, R.; Edgar, G. & Last, P.R. (2020). "Thymichthys politus". IUCN Red List of Threatened Species. 2020: e.T123423510A123424379. doi:10.2305/IUCN.UK.2020-1.RLTS.T123423510A123424379.en. Retrieved 22 March 2024.
- ^ Eschmeyer, William N.; Fricke, Ron & van der Laan, Richard (eds.). "Species in the genus Thymichthys". Catalog of Fishes. California Academy of Sciences. Retrieved 22 March 2024.
- ^ a b c Last, P.R. & Gledhill, D.C (2009). "A revision of the Australian handfishes (Lophiiformes: Brachionichthyidae), with descriptions of three new genera and nine new species.". Zootaxa. 2252 (1). Magnolia Press: 1–77. doi:10.11646/zootaxa.2252.1.
- ^ Nelson, J.S.; Grande, T.C.; Wilson, M.V.H. (2016). Fishes of the World (5th ed.). Hoboken, NJ: John Wiley & Sons. pp. 508–518. doi:10.1002/9781119174844. ISBN 978-1-118-34233-6. LCCN 2015037522. OCLC 951899884. OL 25909650M.
- ^ Christopher Scharpf (14 November 2022). "Order LOPHIIFORMES (part 1): Families LOPHIIDAE, ANTENNARIIDAE, TETRABRACHIIDAE, LOPHICHTHYIDAE, BRACHIONICHTHYIDAE, CHAUNACIDAE and OGCOCEPHALIDAE". The ETYFish Project Fish Name Etymology Database. Christopher Scharpf. Retrieved 18 March 2024.
- ^ Jeffery, Michael I.; Firestone, Jeremy; Bubna-Litic, Karen, eds. (2008), "Sanctuaries, Protected Species, and Politics – How Effective Is Australia at Protecting Its Marine Biodiversity under the Environment Protection and Biodiversity Conservation Act 1999?", Biodiversity Conservation, Law + Livelihoods, Cambridge: Cambridge University Press, pp. 280–305, doi:10.1017/cbo9780511551161.018, ISBN 9780511551161, retrieved 12 April 2023
- ^ a b The PLOS ONE Staff (26 September 2018). "Correction: Local densities and habitat preference of the critically endangered spotted handfish (Brachionichthys hirsutus): Large scale field trial of GPS parameterised underwater visual census and diver attached camera". PLOS ONE. 13 (9): e0205040. doi:10.1371/journal.pone.0205040. ISSN 1932-6203. PMC 6157897. PMID 30256847.
- ^ Jeffery, Michael I.; Firestone, Jeremy; Bubna-Litic, Karen, eds. (2008), "Sanctuaries, Protected Species, and Politics – How Effective Is Australia at Protecting Its Marine Biodiversity under the Environment Protection and Biodiversity Conservation Act 1999?", Biodiversity Conservation, Law + Livelihoods, Cambridge: Cambridge University Press, pp. 280–305, doi:10.1017/cbo9780511551161.018, ISBN 9780511551161, retrieved 12 April 2023
- ^ "Tasmania (Australia), Bass Strait Coast". Journal of Coastal Research. 100 (sp2). 31 December 2022. doi:10.2112/jcr-si100-flat-058.1. ISSN 0749-0208.
- ^ "Researchers Look In Tank And See Promising Cluster Of Nearly-Extinct Babies - The Dodo". www.thedodo.com. Retrieved 3 December 2023.
These sources are from the science citation index. Specifically, they were found through the University of Illinois at Chicago database.