Wednesday, June 24, 2009

Cyrtocara moorii

Also called the blue dolphin of Lake Malawi. A very beautiful fish with an excellent coloration with all grades of blue. "Very peaceful for an African, it will only chase other fish if provoked or when spawning". At least this is what should happen. However, my male C. moorii hasn't read any books so it doesn't behave like that. Very peaceful with most species it fights ferociously with the strongest fish in my tank, the Nimbochromis venustus. Very often you can see both of them with scars and missing scales. Once these fights begin all other fish stay at the tank corners leaving the center to the two gladiators, who may spend an hour chasing each other. Strange as it may sound the moorii is the hyperdominant fish in my tank (something that will presumable change when my Buccochromis nototaenia male reaches adulthood, now a 21 cm "baby").

The moorii will eat any cichlid food offered in big quantities. Provided with lots of space they will spend most of their time swimming around (you must provide them with swimming space). Grows fairly large and should be kept in large tanks only (>500 Lt). Males may exceed 20 cm in length (mine is already about that size) and their body shape calls for too much space. It takes a very long time for this fish to start spawning (almost two years), but when they do they are like a clock ! My pair spawns every 45 days. When trying to remove the carrying female to her one tank you should be very patient and avoid any moves that may frighten the fish. The female will readily spit the eggs in the tank which will be eaten by the other fish on the spot. If caught in a gentle way the female may spit the eggs in the net. After placing her to the new tank, drop the eggs in it. The female will pick them up after an hour or so. Since the fry can't survive with their egg sacks still on their bellies it is preferable to wait at least 14 days before netting the female. Thus, if the eggs are spitted the fry still has a good chance to survive.

Minimum tank size : 150 cm / 500 liters, Recommended tank size : 200 cm / 750 liters. Recommended combination : One male with three or more females in a 1.000 liter tank. Tankmates : large size haps. In a community tank, one female is enough. Lots of open spaces.

Close-up shot: 100 ASA film, 125 mm lens, f/11, 1/60 sec, auto-bellows, Sunpack flash unit (GN:36 at 1/8th setting) taped over the lens, shot from a distance of 20 cm. Flash head tilted slightly to avoid reflections from the glass. Hand-held camera - a really difficult one.


Monday, June 22, 2009

South American Lungfish Amazonian Lungfish Family: Lepidosirenidae

The South American Lungfish may not be pretty, ...but it is pretty amazing!

As its name implies the South American Lungfish actually does have lungs and needs to breath air. The young fish can be quite pretty with gold spots on a black background. As the fish grows, this color will fade to gray or brown.

This fish lives in swampy areas that have the potential to completely dry up during the dry season. When most of the water has dried up and all that is left is mud, it will burrow down leaving 2 or 3 small holes for breathing. A layer of mucous will form around its body to help seal in moisture. During this hibernation, its metabolism will decrease greatly, allowing it to survive for months underground. When the rains come again, it will come out of the mud to resume its life as a fish.

The South American Lungfish, also known as the Amazonian Lungfish, was described by Fitzinger in 1837. The are found in swampy areas throughout the Amazon, Paraguay and lower Paraná River basins.

The species is not listed on the IUCN Red List.

The body of the South American Lungfish looks rather eel like, being elongated and slender. Their pectoral fins are thin and thread-like, and their pelvic fins are a bit larger and set far back on the body. The newly hatched young look similar to tadpoles, but have branched external gills much like those of newts. After 7 weeks the young transform (called metamorphosis) into the adult form, loosing the external gills for gill openings.
Overall, adults have a dark gray or brown coloration. Juveniles will have gold spots on a black background. As the fish grows, this color will fade to gray or brown.

Size - Weight:
These fish can grow to over to 4 feet long (125 cm).

Care and feeding:
The South American Lungfish may be considered omnivores as it has been fairly recently reported that they do ingest some unidentified algae and plant stems. However, they are primarily carnivorous and will eat all types of protein foods. The easiest source of food is fish; live, dead or in pieces. They will also eat insects, shrimp, crayfish, clams or most any living animal that is not quick enough to escape their vacuum like mouth. Tongs can be used to hold food in front of them to make sure it is eaten quickly and won’t have a chance to foul the water.
Housing for this fish only needs to be large enough so that it can stretch out completely. They are not particularly active so a 60 gallon tank should be big enough for most home grown specimens. Lots of swimming space is not necessary. Ideally they like a lots of hiding places with dense vegetation along with some roots and rocks. However this fish must be able to reach the surface to breathe, so make sure the water’s surface is clear of obstructions or else they will drown.

Water Region: Top, Middle, Bottom:
Other than when it is breathing, it will spend most of its time on the bottom of the tank.

Acceptable Water Conditions:
Temp: 75 - 82° F (24 - 28° C)

Social Behaviors:
They aren’t aggressive but may try to eat anything that will fit into their mouths. Although other large fish may survive in the tank with them, there is always the chance that the lungfish may attack or be attacked by other fish. In the case of the lungfish, this will not be caused by aggression but by hunger. Any fish that holds still long enough, including other lungfish, may end up with missing fins.

Sexual Differences:

Has not been bred in captivity. In the wild, adults construct tunnel type holes in the mud that they line with vegetal matter. They then retreat into the tunnel and seal it off. During breeding season the adults do not breath through their lungs, so do not need to go to the surface for air. Rather they breath through use of their gills and through many thin-branched appendages which develop temporarily during this time.
The eggs are laid in the tunnel and guarded by the male, even after the eggs hatch into larvae. When newly hatched the young resemble tadpoles. During the larvae stage they breath through thread-like external gills, much like those of newts. After 7 weeks the young transform (called metamorphosis) into the adult form, loosing the external gills for gill openings.

The South American Lungfish are commonly available but this is not a fish that many stores will carry on a regular basis. It is definitely a candidate for a special order.

Author: Ken Childs
Additional Information: Clarice Brough, CFS
credit form web

Saturday, June 20, 2009

Cetopsis coecutiens (Lichtenstein, 1819)

Cetopsis coecutiens (Lichtenstein, 1819)
This month we welcome back our resident catfish contributor, Chris Ralph, writer and catfish expert in the U.K. fishkeeping magazines. This factsheet is close to my heart, so to speak, as I joined Chris and other catfish buffs on a memorable trip to Peru and the Amazon in 2000 and this catfish was one of the first that I had seen when we caught them from the boat on rod and line. They are not a pretty sight so I will let Chris explain and educate us on the "Whale Cat", Cetopsis coecutiens

Cetopsis coecutiens is one of the largest of the so called species of “Candiru” and is viewed with some trepidation amongst a number of catfish enthusiasts. Unfortunately or fortunately depending upon your personal views, Cetopsis coecutiens is not commonly available to the hobbyist. When this unusual catfish is available, expect to pay £20-£25 per fish. In their natural habitat these catfish are very much opportunist parasites feeding upon other fish, literally biting chunks of flesh from the body of their unfortunate victim. These catfish are often found inside the body cavities of larger fish such as the Red tail catfish – Phractocephalus hemioliopterus and Tiger shovelnose – Pseudoplatystoma fasciatum! These catfish are found in relatively large numbers in their natural habitats.

Cetopsis coecutiens belongs to the family Cetopsidae or Whale Catfishes from South America; namely the Amazon basin, Peru, Bolivia, Colombia, Ecuador, Venezuela and Brazil - Tocantins and Orinoco River basins.

Although it is documented that this catfish reaches a size of 265mm, whilst collecting catfish in Peru in July 2000 a number of specimens were caught on rod and line ( see image below) which exceeded this length and were 300mm+!

Cetopsis coecutiens prefer to be kept in water which has a pH in the range of 6.0-7.4. This catfish is ideally suited to temperatures in the range of 22-28ºC. Cetopsis coecutiens is naturally an open water swimming fish and as such requires well aerated water with a strong current in order to keep it in optimum conditions.

I would suggest a minimum size of Aquaria to be 72” x 24” X 24” if you are going to keep these catfish until they attain adult size. There is no real preference of substrate when keeping these catfish however; I would suggest good quality aquarium sand such as BD Aquarium Sand, or very smooth rounded gravel. The aquarium should provide minimal shelter in the form of rocks or bogwood due to the fact that this catfish is constantly on the go, swimming in the midwater regions of the water body. As with all other species of fish, water quality and general husbandry is very important, and I would recommend that a minimum of 25% water is changed on a weekly basis due to the fact that these catfish are constantly looking for food and the diet is fish or meat based. Lighting should be dim, due to the poor eyesight of these catfish and the fact that they are found at relatively deep water levels in their natural habitat.

Did you know? – This particular catfish was recently featured in the BBC series Amazon Abyss, and was seen still feeding upon the carcass of a catfish even after it was taken out of the water!

The body shape of Cetopsis coecutiens is described as being cylindrical, torpedo or cigar shaped. The body is also best described as being naked or devoid of scales. The pectoral fin spines are not serrated. The eyes are small in comparison to the rest of the body and are often described as being “piggy”. The mouth is relatively large in comparison to the rest of the body with the mandible being under slung, with the maxilla protruding, almost giving the appearance that the fish is smiling

The base colour of the dorsolateral region of the body and head is blue, whilst the ventrolateral region is predominantly white in colour interspersed with some patches of blue towards the head. The dorsal and caudal fins have some blue colouration whilst the remaining fins are white in colour.

Wherever possible I would recommend that the aquarist keep these catfish in a species only aquarium in small groups, but as the absolute minimum I would suggest two to three specimens assuming that they are available in these numbers. In their natural habitat Cetopsis coecutiens would be found in very large shoals. This catfish is not a species to be trusted in with other species due to its ability to bite lumps out of other large fish, and would soon devour any small fish within the confines of its environment. With this information in mind I would not recommend that you keep any other fish with these catfish.

As far as I am aware there are no documented records of Cetopsis coecutiens having been spawned in aquaria to date (but then who would want to?).

Sexual differences
The males tend to be more slender than the females. The dorsal fin of the male tends to be more pointed in mature specimens.

As with all the other catfish that I have had the pleasure to keep over the years, Cetopsis coecutiens readily accepts a mixed but meaty varied diet. I found that these catfish relished meaty foods such as whole mussel, cockles, prawns and earthworms and after a while they even accepted the occasional sinking catfish pellet! A word of caution though, these catfish will easily gorge themselves if given too much food, so you need to ensure that these catfish are not overfed.

Cetopsis: from the Greek cetos which means whale, and cosis which means like, hence the reference to this catfish being whale-like in appearance.

Ventrolateral: is defined as extending from below and to the side.
Dorsolateral: is defined as extending from the top to the side.
Maxilla: is defined as the bone of the upper jaw.
Mandible: is defined as the lower jaw.

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Crayfish and lobsters

Crayfish and lobsters can be found in a variety of cooler waters, and there have been some problems with crayfish making an overpowering appearance outside of their native waters. For that reason certain species can be hard to find in aquatics centres, and you may need a licence to keep non-native specimens. All varieties sport glorious colours, they are however best kept in a specimen or species aquarium. Their aquarium should be furnished with rocks and plastic plants and roots as real plants will be destroyed. If more than one crayfish is to be kept in a tank they will need a lot of space as they are both territorial and cannibalistic. Also after a cray has moulted it becomes very vulnerable, if it is kept with anything that may attack it (like another crayfish) then the cray should be removed/separated until the carapace hardens. Crayfish are nocturnal and are best viewed after lights out, they should also be fed around lights out until they adopt a diurnal existence. They will readily hand feed once settled. Feed an omnivorous diet, including shrimp pellets, small fish, lean meats, worms, cockles and other frozen foods. Any uneaten food should be removed quite quickly as they have a tendency to hide hoards of food.

In the more evolved form of reproduction, the fry are usually born as miniature versions of the adults. Usually limited to crayfish and shrimp, it is also found in some species of crabs; namely the Potamon family of land crabs.
The larvae will hatch after up to 28, days and the young are almost fully-formed within the eggs during this time. Once born the only anatomical feature not present is the reproductive organs.
They eat almost the same food as the parents (just scaled down in size), and will develop and grow very quickly.

They are usually fairly easy to breed under aquarium conditions, and will be cared for by their mother until released (when some cannibalism may occur).
As the more specialised fry have a much better survival rate than the primitive fry, the females produce fewer eggs (from only 7 up to 300 depending on species and condition) making the numbers more manageable.

The most important stage of their development is their first 24 hour period, during this time the fry will undergo their first moult, and many will not survive. Only the fry that survive the first two weeks have a good change of reaching adulthood.
The water should be changed frequently during this period, and quality needs to be kept good to assure a higher survival rate.

Some species, like the long-arm shrimp, will be born as floating larvae, and will only start crawling after this period. These species need to be fed small live feeds such as newly hatched brine shrimp or microworms, or Liquifry type foods, but care should be taken to ensure the water doesn't become too polluted.

The juveniles will look very different in colour to the parents, usually appearing transparent and well camouflaged. Their colours will change only when they reach sexual maturity, and start to attract a mate. Some species, especially crayfish, may predate on their smaller siblings too, so you may need to segregate them as they grow.

The mating process is rarely witnessed, the only evidence that it has happened is the eggs held within the females pleopods.
During the ritual, the males will attract (or entrap) a female, and they will copulate in the 'Y' position for a short time, continually cleaning and preening each other throughout.

Cherax holthuisi

Cherax zebra

Cherax sp. Tricolor

Cherax sp. blue moon

Cherax sp. redbrick

Cherax destructor

Procambarus clarkii blue

Procambarus clarkii

Procambarus clarkii orange ( My Cray :P )

Procambarus clarkii white ( My Cray too)

Cherax sp. Orange Tip

Cherax Preissii Black jet

credit from