Australian Aquatic Biological

Australian aquatic biodiversity research and consultancy

Orbost Spiny Crayfish paper finally published

Euastacus diversus from Ellery Creek (Brodribb drainage) showing 2 marginal squamal spines

Euastacus diversus from Ellery Creek (Brodribb drainage) showing 2 marginal squamal spines

Started in 2005 the quest to rediscover the Orbost Spiny Crayfish Euastacus diversus has been a long and intriguing journey cumulating in the publication of this paper.

This story began back in 1959 when one of Australia’s foremost expert on freshwater crayfish at that time, Edgar Riek, discovered this small freshwater crayfish species in the east Gippsland region of Victoria. Then in 1969 he described the species and named it Euastacus diversus. Since that day this crayfish has remained a rare and elusive species.

In 1986, the then current expert on the genus Euastacus, Gary Morgan, searched for this species but was unable to find any in the wild. As a consequence he redescribed the handful of original specimens collected by Riek in 1959 that are held at the Australian Museum. Gary Morgan’s detailed description, published in the Memoirs of the Museum of Victoria 30th May 1986, was the latest scientific publication on this species and forms the basis of all current information and opinions until now.

In 2005, the Australian Crayfish Project (ACP) was started, involving one of the largest projects researching freshwater crayfish ever seen in Australia. Between 2005 and 2007 we also failed to find any specimens of Euastacus diversus for the type locality general area 40 miles north of Orbost. Then in 2007 we changed our methods and successfully started finding more and more specimens. Up to 2011 a considerable number of E. diversus and other Euastacus species were found in the wild. The project has been very successful in finding this and other crayfish species, and large areas of southern NSW and eastern Victoria were systematically biologically surveyed specifically for freshwater crayfish. We found Euastacus specimens everywhere and most did not match the description for the known species leading to much confusion. However, genetic analysis by the Carnegie Museum of Natural History in the USA helped clarify the situation resulting in the thorough redescription of E. diversus and the discover of a number of new species.

Euastacus diversus redescription 2015

Euastacus diversus redescription 2015

The research culminated in this paper titled “Re-description of the Orbost Spiny Crayfish, Euastacus diversus Riek 1969 (Decapoda: Parastacidae), in Eastern Victoria, Australia” published in the journal “Freshwater Crayfish”. The paper redescribes Euastacus diversus to include the Bonang River crayfish (previously thought to be a new species).

The Bonang River crayfish from the most northern extent of distribution

The Bonang River crayfish from the most northern extent of distribution

The Bonang taxon represent a morphologically distinct population of Euastacus diversus that is genetically 1.95% divergent from the E. diversus type locality populations.

Euastacus diversus from Riddle Creek

Euastacus diversus from Riddle Creek

The research extends the distribution of the species to the Brodribb, Yalmy, Rodger and Bonang River drainages at elevations ranging from 350 – 950 m a.s.l., with an overall Extent of Occurrence of 465 km2. Research continues on E. diversus which will surely increase the Extent of Occurrence. Research also continues on the new Euastacus species and hopefully the first of the new species descriptions will be published later this year.

Citation:

Coughran J, McCormack RB and Fetzner Jr. JW (2015). Re-description of the Orbost spiny crayfish, Euastacus diversus Riek 1969 (Decapoda: Parastacidae), in eastern Victoria, Australia. Freshwater Crayfish 21(1): 185-197.

 

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A guide to Australia’s Spiny Freshwater Crayfish

The “NEW BOOK” will hit the bookshop in July 2012

A guide to Australias Spiny Freshwater Crayfish

A guide to Australias Spiny Freshwater Crayfish

Preface

Australia is the lucky country with the three largest freshwater crayfish species in the world. The largestis the Giant Tasmanian Freshwater Crayfish (Astocopsis gouldi), next is the Murray Lobster (Euastacus armatus) and then the West Australian Marron (Cherax cainii).

This publication refers to Australia’s Euastacus Crayfish which are the largest of the 10 genera of Australian freshwater crayfish. We cover the full 50 Euastacus species found in Australia, from the iconic giant Murray Lobsters (Euastacus armatus) that are recreationally fished to the exceedingly rare tiny species, like Euastacus maidae from the NSW/Qld coastal border region. These uniquely Australian mainland crayfish range from Cooktown in far north Queensland to Wilsons Promontory in Victoria, the southernmost point of the Australian mainland. Many are found in or around major population centres, making them well known to many people. For example, Euastacus spinifer and Euastacus australasiensis are found throughout the Sydney region. Euastacus yarraensis is found around Melbourne and Euastacus sulcatus from the outskirts of Brisbane.

They are referred to as the “Spiny Crayfish” due to impressive arrays of spines on their hard armoured shells. Most species are very colourful with their spines in highlighted colours that enhance their size and shape. Owing to their unique colouration, wide distribution and in many cases impressively large size, these species are of interest to a huge section of the community.

The giant spiny crayfish are the pinnacle for crayfish enthusiasts and I have always had a passion for crayfish and have spent my life either catching them for pets or growing them commercially. For over 20 years I have made a living by culturing both Cherax and Euastacus crayfish commercially. All my time and efforts over that period have been devoted to making a living from the aquaculture of crayfish. Aquaculture is not for the weak, it’s a tough life with small profit margins. When I started little known about freshwater crayfish aquaculture, so I had to learn as I went and just about every mistake that could be made, I made. Over the years, with the help of the researchers and crayfish gurus from around Australia, I eventually learnt the recipe for success in crayfish farming and my farm prospered. Now I have sold the farm and have the time and resources to follow my passion for freshwater crayfish and I am investigating all of those species that this continent has to offer.

The Australian Crayfish Project (ACP) was conceived to increasing the knowledge base on all our Australian crayfish species and the promotion of the conservation and protection of these crayfish and their fragile habitats. Over the years I have come across numerous species that were undescribed and unknown by the authorities and there seemed to be huge gaps in the most basic knowledge of so many of these unique native species. We are extremely lucky in Australia, there are vast areas of State Forests and National Parks that offer perfect refuges for our native crayfish and we are still discovering species that have never been seen before. With the help of scientists, researchers and enthusiasts the ACP is investigating and recording knowledge of all of our crayfish species.

This book provides the most up to date information collected over the last seven years as part of the ACP on the species, their identification, biology and distributions. Many of these species are in desperate need of protection and conservation management and we hope you will share our concern and add your voice to help protect and conserve them for all eternity.