The new and the known: describing freshwater fish species

September 2001 The discovery of new vertebrate Additional specimens were collected Yalangi Aboriginal people to use a species is a very rare event in . in 1994 and laboratory work on them traditional word in the description and Rainforest CRC researcher Dr Brad commenced. The specimens were also in being so generously granted Pusey has recently described not one, measured, dissected and x-rayed,their access to the beautiful Bloomfield but two new species of freshwater fish physical features were counted and River. The genus name is derived from endemic to the Wet Tropics region. specimens genetically tested for the Kuku-Yalangi word “kuyu” which Their description sheds light on the comparison with other species within means freshwater fish. The letter “k” uniqueness and antiquity of the fauna. the family. The result – not only a new is pronounced phonetically as “g” in species but a new genus as well! Aboriginal languages. Kuyu is used Describing a new species Groups of closely related species are similarly by other language groups of In 1993, Brad and his co-workers, Mark placed in a genus. A formal descrip- north Queensland. The species name Kennard of Griffith University and tion was prepared and circulated wujalwujalensis denotes that the new Andrew Sheldon of the University of amongst Australian fish taxonomists species occurs near the township of Montana, surveyed the fish fauna of before being accepted by the special- Wujal Wujal. It was felt that the name the Bloomfield River as part of a larger ist journal Ichthyological Explorations of not only suits the new species well but study of the freshwater fish diversity Freshwaters. The species description also conveys some impression of the of the Wet Tropics. Among the many finally appeared in print in 2001. A strong link between Aboriginal people interesting fishes collected, were 13 long time but worth the wait. and their relationship with the land. specimens of a very odd looking little fish. They recognised that the fish Naming the species Guyu wujalwujalensis occurs nowhere belonged to the family Percichthyidae, The name selected for the new species else but the Bloomfield River and is which contains the well-known was Guyu wujalwujalensis. The genus further restricted to only that part of Murray Cod and Yellowbelly, but were name is a departure from the usual the river between the downstream puzzled as to its specific identity. Even practice of using latin. Bloomfield Falls and the upstream more puzzling was the fact that no Roaring Meg Falls. As such it has one Percichthyidae had ever been collected We were most fortunate in being of the most geographically limited from tropical Australian freshwaters. granted permission by the Kuku- distributions of any of the region’s freshwater fishes. Its origins are prob- Bloomfield River Cod (Guyu wujalwujalensis) ably very ancient, and may date back to the late Cretaceous, some 70-100 million years ago. It may represent what remains of a previously more widespread fauna that is now confined to temperate and sub-tropical Australia. Given these factors, it has a very high conservation significance and is therefore listed as “Vulnerable” by Environment Australia. It is likely that the single greatest threat to its continued existence is the introduction Photo: Mark Kennard or translocation of fish into the Bloomfield River. Redescribing a known species In addition to its importance to the The second fish proved more an exer- purely scientific pursuit of under- cise in redescribing than describing. standing the evolutionary history and This was the khaki bream (Hepahestus biogeography of different groups, the tulliensis) another endemic Wet Trop- recognition of what constitutes an ics species superficially similar to the individual species has more immedi- black bream or sooty grunter ate and practical concerns. (Hepahestus fuliginsosus), a widespread species of angling and culinary Many management strategies are renown. While it has long been Khaki bream ( tulliensis) focused on individual species. If we recognised as being distinct by anglers photo: Gerry Allen don’t know what species we are and some fisheries personnel, the trying to manage, how can we do so specific identity of the khaki bream In such cases, historical precedence effectively? For example, H. tulliensis has remained a mystery. Brad and his determines which name is valid. The is found nowhere else but the Wet co-worker, Dr Gerry Allen of the West- recognition of synonomy usually Tropics, in contrast to the more wide- ern Australian Museum, commenced occurs when a taxonomic group such spread distribution of its relative H. writing a formal description but in as a family or genus is being revised. fulignisosus. Accordingly, H. tulliensis doing so found they had been beaten must be viewed as having a higher to the punch, by over 100 years! Such revisions are necessary to ensure conservation significance. Moreover, that nomenclature remains correct and the reproductive ecology and habitat Duplication and errors when species accurate and to ensure that taxonomic requirements of H. tulliensis differ from are described associations, such as species within that of H. fuliginosus. Management The khaki grunter was originally genera or genera within families, guidelines such as minimum size described, as H. tulliensis, by C.W. De accurately reflect evolutionary history. limits and bag sizes designed for the Vis in 1884. For reasons which remain Sometimes this process may result in protection of one species may not difficult to fathom, the name was long familiar names being changed to adequately protect, and may in fact be either never adopted or rapidly something new. It may result in detrimental, to another species if they dropped out of usage. In a 1978 lumping, where species formerly are not recognised as being distinct. revision of the family , considered distinct are collapsed into (the grunters) it was considered not to a single species, or alternatively in Two of the region’s endemic fishes be a valid species, but rather a splitting, where a single species is now have scientific names. Other “synonym” of another species H. divided up into several new species. endemic fishes of the region are yet to fuliginosus. On occasions, the decisions made be formally described, however. These during revisions may be in error, such include fishes from such diverse Synonomy occurs when two different as the recognition of the synonomy of groups as rainbowfish, hardyheads, authors describe and attribute differ- H. tulliensis and H. fuliginosus. In this catfish and gobies. The work goes on! ent names to the same species. case, the error arose because of a Synonomy in Australian freshwater failure to examine specimens of both For more information contact: fishes occurred fairly frequently in the species from the Wet Tropics region. Dr Brad Pusey late 19th century when many new Faculty of Environmental Science species were being described but Why describe species at all? Griffith University communication between researchers What is the relevance of this rather NATHAN, QLD 4870 was limited. technical and specialised activity? Phone and Fax: (08)9751 2265 Email: [email protected]