Pterophyllum is a small genus of freshwater fish from the family Cichlidae known to most aquarists as angelfish. All Pterophyllum species originate from the Amazon Basin, Orinoco Basin and various rivers in the Guiana Shield in tropical South America. The three species of Pterophyllum are unusually shaped for cichlids being greatly laterally compressed, with round bodies and elongated triangular dorsal and anal fins. This body shape allows them to hide among roots and plants, often on a vertical surface. Naturally occurring angelfish are frequently striped transversely, colouration which provides additional camouflage. Angelfish are ambush predators and prey on small fish and macroinvertebrates. All Pterophyllum species form monogamous pairs. Eggs are generally laid on a submerged log or a flattened leaf. As is the case for other cichlids, brood care is highly developed.
Monogeneans, members of the class Monogenea, are a group of ectoparasitic flatworms commonly found on the skin, gills, or fins of fish. They have a direct lifecycle and do not require an intermediate host. Adults are hermaphrodites, meaning they have both male and female reproductive structures.
The sailfin molly is a livebearer fish typically found in both freshwater and brackish waterways along the East Coast of the United States, from North Carolina south to Florida, and around the Gulf of Mexico to Texas, and south to the Yucatán Peninsula of México. Given their preference for more brackish water conditions, mollies are often found within just a few yards or miles of the ocean, inhabiting coastal estuaries, lagoons, river deltas and swamps, as well as tidal areas with a regular inflow of oceanic minerals and nutrients mixing with inland freshwater sources.
Fin rot is a symptom of disease or the actual disease in fish. This is a disease which is most often observed in aquaria and aquaculture, but can also occur in natural populations.
Myxobolus cerebralis is a myxosporean parasite of salmonids that causes whirling disease in farmed salmon and trout and also in wild fish populations. It was first described in rainbow trout in Germany in 1893, but its range has spread and it has appeared in most of Europe, the United States, South Africa, Canada and other countries from shipments of cultured and wild fish. In the 1980s, M. cerebralis was found to require a tubificid oligochaete to complete its life cycle. The parasite infects its hosts with its cells after piercing them with polar filaments ejected from nematocyst-like capsules. This infects the cartilage and possibly the nervous tissue of salmonids, causing a potentially lethal infection in which the host develops a black tail, spinal deformities, and possibly more deformities in the anterior part of the fish.
Ceratonova shasta is a myxosporean parasite that infects salmonid fish on the Pacific coast of North America. It was first observed at the Crystal Lake Hatchery, Shasta County, California, and has now been reported from Idaho, Oregon, Washington, British Columbia and Alaska.
Velvet disease is a fish disease caused by dinoflagellate parasites of the genera Amyloodinium in marine fish, and Oodinium in freshwater fish. The disease gives infected organisms a dusty, brownish-gold color. The disease occurs most commonly in tropical fish, and to a lesser extent, marine aquaria. Periodic use of preventive treatments like aquarium salt can further deter parasites. Regular monitoring, attentive care, and preventive measures collectively contribute to keeping Goldfish health and Velvet-free.
The common goldfish is a breed of goldfish and a family of Cyprinidae in the order cypriniformes. Goldfish are descendants of wild carp from East Asia. Most varieties of fancy goldfish were derived from this simple breed. Common goldfish come in a variety of colors including red, orange, red/white, white/black, yellow/white, blue, grey/brown, olive green, yellow, white, and black, with the most common variation being orange, hence the name. The brightness, duration, and vividness of the color may be an indication of the fish's health status, but not always, as water conditions and quality of care affect the fish's appearance.
Lymphocystis is a common viral disease of freshwater and saltwater fish. The virus that causes this disease belongs to the genus Lymphocystivirus of the family Iridoviridae.
A xenoma is a growth caused by various protists and fungi, most notably microsporidia. It can occur on numerous organisms; however is predominantly found on fish.
Cryptocaryon irritans is a species of ciliates that parasitizes marine fish, causing marine white spot disease or marine ich. It is one of the most common causes of disease in marine aquaria.
Oodinium is a genus of parasitic dinoflagellates. Their hosts are salt- and fresh-water fish, causing a type of fish velvet disease. One species has also been recorded on various cnidarians.
Ornamental fish kept in aquariums are susceptible to numerous diseases. Due to their generally small size and the low cost of replacing diseased or dead fish, the cost of testing and treating diseases is often seen as more trouble than the value of the fish.
Dactylogyrus is a genus of monogeneans in the Dactylogyridae family.
Dactylogyrus vastator is a species of monoic flatworms of class Monogenea. It is an ectoparasite of fish which infests the gills. It is problematic on fish farms. It is otherwise non-hazardous to humans.
The guppy, also known as millionfish or the rainbow fish, is one of the world's most widely distributed tropical fish and one of the most popular freshwater aquarium fish species. It is a member of the family Poeciliidae and, like almost all American members of the family, is live-bearing. Guppies originate from northeast South America, but have been introduced to many environments and are now found all over the world. They are highly adaptable and thrive in many different environmental and ecological conditions. Male guppies, which are smaller than females, have ornamental caudal and dorsal fins. Wild guppies generally feed on a variety of food sources, including benthic algae and aquatic insect larvae. Guppies are used as a model organism in the fields of ecology, evolution, and behavioural studies.
Like humans and other animals, fish suffer from diseases and parasites. Fish defences against disease are specific and non-specific. Non-specific defences include skin and scales, as well as the mucus layer secreted by the epidermis that traps microorganisms and inhibits their growth. If pathogens breach these defences, fish can develop inflammatory responses that increase the flow of blood to infected areas and deliver white blood cells that attempt to destroy the pathogens.
Hematodinium is a genus of dinoflagellates. Species in this genus, such as Hematodinium perezi, the type species, are internal parasites of the hemolymph of crustaceans such as the Atlantic blue crab and Norway lobster. Species in the genus are economically damaging to commercial crab fisheries, including causing bitter crab disease in the large Tanner or snow crab fisheries of the Bering Sea.
Diseases and parasites in salmon, trout and other salmon-like fishes of the family Salmonidae are also found in other fish species. The life cycle of many salmonids is anadromous, so such fish are exposed to parasites in fresh water, brackish water and saline water.
Amyloodinium ocellatum is a cosmopolitan ectoparasite dinoflagellate of numerous aquatic organisms living in brackish and seawater environments. The dinoflagellate is endemic in temperate and tropical areas, and is capable of successfully adapting to a variety of different environments and to a great number of hosts, having been identified in four phyla of aquatic organisms: Chordata, Arthropoda, Mollusca and Platyhelminthes. Moreover, it is the only dinoflagellate capable of infecting teleosts and elasmobranchs.
