| East Gippsland spiny crayfish | |
|---|---|
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Subphylum: | Crustacea |
| Class: | Malacostraca |
| Order: | Decapoda |
| Suborder: | Pleocyemata |
| Family: | Parastacidae |
| Genus: | Euastacus |
| Species: | E. bidawalus |
| Binomial name | |
| Euastacus bidawalus Morgan, 1986 | |
Euastacus bidawalus, the East Gippsland spiny crayfish, is an Australian freshwater crayfish endemic to the East Gippsland area of Victoria and the far south coast of New South Wales.
The East Gippsland spiny crayfish is similar in overall appearance to other members of the Genus and is morphologically similar to the Orbost Spiny Crayfish Euastacus diversus. Maximum recorded occipital carapace length (OCL) is 48 mm (1.9 in). The rostrum is short reaching at most the middle of the third segment of the antenna, often only to the base of that segment. The cephalon (head) is generally poorly to moderately spined with relatively few spines, of small size or rounded bumps. Sharp spines sometimes found on smaller specimens. The thorax has a line of five to eight medium small to medium large spines on either side, the dorsal spine often larger and sharper than the others. The abdomen is divided into segments, with dorso-lateral spines absent on the first segment. Four to seven spines in the first line on segment two, on specimens above 30 mm (1.2 in) OCL. On segments three to five there is usually one spine in the first line. First line spines are larger and sharper to very sharp on larger individuals, above 40 mm (1.6 in). A second line of spines is generally poorly developed, being absent to tiny in smaller animals, under 30 mm (1.2 in), and tiny to small on larger specimens. There are two to three spines on segments two and three in a second line on most crayfish above 30 mm (1.2 in), rarely on segments four and five and absent on segment six. There are no spines on the tailfan. [2]
E. bidawalus is green-brown or red-brown on the back, paler on the sides to cream and orange on the belly. The carpus of the main claw is orange or brown with green or blue mottling and mid line spines green. The produpus is similar to the carpus with cream side spines and the outside edge pale and the inside edge green or blue. Fingers and claws are blue-green. [2]
The East Gippsland spiny crayfish has been recorded at elevations of 150–400 m (490–1,310 ft) from south and east flowing rivers from Lind National Park, about 20 km west of Cann River, to near Mount Imlay south of Eden. [4]
Spends most of its life in extensive burrows coming out only at night. Prefers marginal areas such as the edges of streams, and swampy areas in dry sclerophyll forest, also cleared areas with remnant vegetation along streams. [5] [2]
Breeding starts around May to June with the eggs being carried by the female until about December or January. Eggs are large and fecundity is relatively low with typical clutches of between 20 and 40 eggs. Females mature at around 40 mm (1.6 in) OCL. [5]
Listed as endangered by Coughran & Furse, [1] the East Gippsland crayfish is relatively common within the suitable although patchy areas in its range. [5]
Not suitable for human consumption due to their small size, never reaching the minimum legal size in both Victoria and New South Wales of 90 mm (3.5 in) OCL. [5] [6] [7]
Crayfish are freshwater crustaceans belonging to the clade Astacidea, which also contains lobsters. In some locations, they are also known as baybugs, crabfish, crawfish, crawdaddies, crawdads, freshwater lobsters, mountain lobsters, mudbugs, rock lobsters, signal crawfish, or yabbies. Taxonomically, they are members of the superfamilies Astacoidea and Parastacoidea. They breathe through feather-like gills. Some species are found in brooks and streams, where fresh water is running, while others thrive in swamps, ditches, and paddy fields. Most crayfish cannot tolerate polluted water, although some species, such as Procambarus clarkii, are hardier. Crayfish feed on animals and plants, either living or decomposing, and detritus.
Cherax, commonly known as yabby/yabbies in Australia, is the most widespread genus of fully aquatic crayfish in the Southern Hemisphere. Various species of cherax may be found in both still and flowing bodies of freshwater across most of Australia and New Guinea. Together with Euastacus, it is also the largest crayfish genus in the Southern Hemisphere.
The river blackfish is a freshwater fish endemic to the temperate waters of south-eastern Australia. It is found from southern Queensland through to central Victoria, including in the Murray-Darling river system. It is also found in some eastern and southern flowing coastal rivers. Found primarily in upland and "midland" habitats, though early records of fish fauna suggest it was originally far more extensively distributed and was found in some lowland habitats as well. Originally, river blackfish co-inhabited many of its lowland and "midland" habitats with species such as Murray cod and golden perch, and its upland habitats with species such as trout cod and Macquarie perch. It is a popular angling fish in some parts of its range.
The common yabby is an Australian freshwater crustacean in the Parastacidae family. It is listed as a vulnerable species of crayfish by the International Union for Conservation of Nature (IUCN), though wild yabby populations remain strong, and have expanded into new habitats created by reservoirs and farm dams.
The Murray crayfish, Euastacus armatus, is a species of freshwater crayfish endemic to Australia that belongs to the family Parastacidae. The Murray crayfish has the largest geographic range of any of the Euastacus crayfish in Australia, being found in the Murray and Murrumbidgee Rivers as well as many of their tributaries. Murray crayfish are also known as "Murray River crayfish", "Murray crays", "freshwater crays", "spiny freshwater crays", "spinies" and in the Wagga Wagga region of southern New South Wales they are simply known as "lobsters".
Euastacus is a genus of freshwater crayfish known as "spiny crayfish". They are found in the south-east of the Australian mainland, along with another genus of crayfish, Cherax. Both genera are members of the family Parastacidae, a family of freshwater crayfish restricted to the Southern Hemisphere.
The Fortescue grunter is a species of freshwater ray-finned fish, a grunter from the family Terapontidae. It is endemic to rivers in Western Australia.
The channel darter is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is native to North America where it typically occurs in the sandy or gravelly shallows of lakes and in small and medium-sized rivers in riffles over sand, gravel or rock bottoms. It is a small fish ranging from 34 to 72 mm in length, olive brown with darker speckles and sometimes with a dark spot below the eye and dark blotches along the flank. It feeds mostly on insect larvae and other small invertebrates and breeds in small streams. This species is listed as threatened by the Canadian Species at Risk Act (SARA) but overall it has a wide range and numerous sub-populations and the International Union for Conservation of Nature has rated it as a "least concern species".
Crustaceans may pass through a number of larval and immature stages between hatching from their eggs and reaching their adult form. Each of the stages is separated by a moult, in which the hard exoskeleton is shed to allow the animal to grow. The larvae of crustaceans often bear little resemblance to the adult, and there are still cases where it is not known what larvae will grow into what adults. This is especially true of crustaceans which live as benthic adults, more-so than where the larvae are planktonic, and thereby easily caught.
Palaeoechinastacus australianus is a species of freshwater crayfish known from Early Cretaceous fossils from Victoria, Australia.
Euastacus spinifer is a species of freshwater crayfish endemic to Australia that belongs to the family Parastacidae.
Chaceon bicolor is a species of crab. Chaceon bicolor differs from all species of the genus in color pattern, with the anterior part of the body purplish rather than reddish. In addition to color pattern, C. bicolor also differs from C. granulatus in having compressed rather than depressed dactyli on the walking legs; also, the hepatic region of the carapace in C. granulatus is coarsely granular, whereas it is smooth in C. bicolor. Juvenile specimens differ from adults in many features: the teeth of the carapace are much larger and sharper, there is a sharp spine on the carpus of the cheliped and a distal spine on the merus of each walking leg, plus the legs are longer and slenderer. Adult females differ from males in having much sharper anterolateral teeth on the carapace, sharper suborbital spines, and much shorter legs, with less trace of a distal dorsal projection on the merus. The carapace of females is more strongly arched from front to back and the protogastric regions are noticeably more inflated. The species is named as such because of its colour patter, purple an tan.
Panulirus penicillatus is a species of spiny lobster that lives on shallow rocky and coral reefs in the tropical Indo-Pacific region. Common names for this spiny lobster include variegated crayfish, tufted spiny lobster, spiny lobster, Socorro spiny lobster, red lobster, pronghorn spiny lobster, golden rock lobster, double spined rock lobster and coral cray. It has a very wide range and the International Union for Conservation of Nature has assessed its conservation status as being of "least concern".
Charybdis hellerii, the Indo-Pacific swimming crab or spiny hands is a species of crab from the swimming crab family, the Portunidae. Its native range covers the Indian and Pacific Oceans but it has been introduced to the western Atlantic and has invaded the Mediterranean. It is a commercially exploited species in south-east Asia.
Euastacus guruhgi is a species of freshwater crayfish found in the Australian state of New South Wales. It has an estimated extent of occurrence of 80 square kilometres (31 sq mi) and an area of occupancy of 7.5 square kilometres (2.9 sq mi) where it occurs fragmentedly. The species has been assessed as a critically endangered species due to a continuing decline in the quality of its habitat due to the invasive exotic species in the area, some of which predate upon this species. Furthermore, there is a continual destruction of its suitable rainforest habitat. E. guruhgi also faces the consequences of global warming; as a restricted range species, it is dependent on cool headwater streams and a slight increase in the temperature of the water could rapidly eradicate the species. There are no specific conservation measures for this species in place but the distribution range of the E. guruhgi falls within the Mount Warning and Wollumbin national parks. In New South Wales, there is a minimum recreational size limit of 90 mm orbital carpace length for any spiny crayfish. E. guruhgi does not attain that size, and is thus, indirectly protected by this restriction.
Euastacus dalagarbe is a species of freshwater crayfish endemic to Australia that belongs to the family Parastacidae. It has a small range in New South Wales and is regarded by the International Union for Conservation of Nature as "critically endangered".
Galaxias lanceolatus, the tapered galaxias, is a galaxiid of the genus Galaxias, a member of the Mountain Galaxias species complex group of freshwater fish, found in Australia.
Galaxias terenasus, the roundsnout galaxias, is a galaxiid of the genus Galaxias, a member of the Mountain Galaxias species complex group of freshwater fish, found in Australia.
Euastacus yanga, also known as the variable spiny cray, is a freshwater crayfish endemic to south eastern Australia.
