Dibrachichthys is a monospecific genus belonging to the family Tetrabrachiidae, the four-armed frogfishes. The only species in the genus is Dibrachichthys melanurus, the twoarm humpback anglerfish, which is found in the eastern Indian and western Pacific Oceans.
| Dibrachichthys | |
|---|---|
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Lophiiformes |
| Family: | Tetrabrachiidae |
| Genus: | Dibrachichthys Pietsch, J. W. Johnson & R. J. Arnold, 2009 |
| Species: | D. melanurus
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| Binomial name | |
| Dibrachichthys melanurus Pietsch, J. W. Johnson & R. J. Arnold, 2009
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Taxonomy
editDibrachichthys was first proposed as a genus in 2009 by Theodore Wells Pietsch III, Jeffrey W. Johnson and Rachel J. Arnold when they described Dibrachichthys melanurus.[2] The type locality of the new species was given as 11°06.9'S, 142°51.9'E, northeast of Ussher Point on the Cape York Peninsula in Queensland.[3] This genus is one of two genera, both monotypic, in the family Tetrabrachiidae. The Tetrabrachiidae is classified within the suborder Antennarioidei within the order Lophiiformes, the anglerfishes.[4]
Etymology
editDibrachichthys combines di, meaning "two", brachium, meaning "arm", and ichthys, which means "fish". This is an allusion to the possession f a single undivided pectoral fin on each side, in contrast to the split pectoral fins of the only other species in the Tetrabrachiidae, Tetrabrachium ocellatum which has its pectoral fins divided. The specific name melanurus means "blacktail", and is a reference to the black bar on the base of the caudal fin.[5]
Description
editDibrachichthys has its dorsal fin supported by 14 or 15 soft rays and the anal fin is supported by between 8 and 10 soft rays. It is very similar to T.. ocellatum but has a single, non divided pectoral fin on each side instead of T. ocellatum's split pectoral fins. The cranium is markedly wider than that of T. ocellatum and some of the skull bones form a horizontal tube-like structure t the front of each eye. The eyes are set in a deep semi-circular protective cavity and there is adeep depression in the middle of the cranium. The coloration is different too with a dark inside of the mouth, a dark bar on the back just below the base of the dorsal fin and a dark bar on the base of the caudal fin. Males have a maximum published standard length of 5.7 cm (2.2 in), while females are slightly smaller with a maximum published standard length of 5.6 cm (2.2 in).[6]
Distribution and habitat
editDibrachichthys is found in the Australia, Papua New Guinea and Indonesia.[1] In Australia it is found around the north from southwest of Dongara in Western Australia to east of Yeppoon in the Capricorn Islandsoff Queensland]. It also occurs in the Aru Islands of Indonesia and the Torres Strait off Papua New Guinea.[7] This is a demersal fish found at depths between 5 and 63 m (16 and 207 ft), although two specimens were collected between 128 and 146 m (420 and 479 ft), on soft substrates of sand and mud in nearsgore waters and in areas with rubble on the continental shelf.[1]
Biology
editDibrachichthys appears to be solitary and individuals are widely dispersed.[6] The eggs are laid by the female in tight clusters bound with filaments. The females have the tips of some of the dorsal fin rays free of the membrane and in T. ocellatum, and probably in this species, the filaments of the egg cluster entangle round these tips and are kept their until they hatch.[8]
References
edit- ^ a b c Ho, H. (2020). "Dibrachichthys melanurus". IUCN Red List of Threatened Species. 2020: e.T140349877A140859717. doi:10.2305/IUCN.UK.2020-1.RLTS.T140349877A140859717.en. Retrieved 30 April 2024.
- ^ Eschmeyer, William N.; Fricke, Ron & van der Laan, Richard (eds.). "Genera in the family Tetrabrachiidae". Catalog of Fishes. California Academy of Sciences. Retrieved 30 April 2024.
- ^ Eschmeyer, William N.; Fricke, Ron & van der Laan, Richard (eds.). "Species in the genus Dibrachichthys". Catalog of Fishes. California Academy of Sciences. Retrieved 30 April 2024.
- ^ 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 30 April 2024.
- ^ a b Froese, Rainer; Pauly, Daniel (eds.). "Dibrachichthys melanurus". FishBase. february 2024 version.
- ^ Dianne J. Bray. "Dibrachichthys melanurus". Fishes of Australia. Museums Victoria. Retrieved 30 April 2024.
- ^ Pietsch, T.W.; J.W. Johnson; and R.J. Arnold (2009). "A new genus and species of the shallow-water anglerfish family Tetrabrachiidae (Teleostei: Lophiiformes: Antennarioidei) from Australia and Indonesia". Copeia. 2009 (3): 483–493. doi:10.1643/CI-08-192. JSTOR 25622931.