Priapulida, sometimes referred to as penis worms, is a phylum of unsegmented marine worms. The name of the phylum relates to the Greek god of fertility, because their general shape and their extensible spiny introvert (eversible) proboscis may resemble the shape of a human penis. They live in the mud and in comparatively shallow waters up to 90 metres (295 ft) deep. Some species show a remarkable tolerance for hydrogen sulfide, anoxia and low salinity. Halicryptus spinulosus appears to prefer brackish shallow waters. They can be quite abundant in some areas. In an Alaskan bay as many as 85 adult individuals of Priapulus caudatus per square meter has been recorded, while the density of its larvae can be as high as 58,000 per square meter.
Cypriniformes is an order of ray-finned fish, which includes many families and genera of cyprinid fish, such as barbs, gobies, loaches, botias, and minnows. Cypriniformes is an "order-within-an-order", placed under the superorder Ostariophysi—which is also made up of cyprinid, ostariophysin fishes. The order contains 11–12 families, over 400 genera, and more than 4,250 named species; new species are regularly described, and new genera are recognized frequently. Cyprinids are most diverse in South and Southeast Asia, but are entirely absent from Australia and South America. At 112 years old, the longest-lived cypriniform fish documented is the bigmouth buffalo.
Cobitidae, also known as the true loaches, is a family of Old World freshwater fish. They occur throughout Eurasia and in Morocco, and inhabit riverine ecosystems. Today, most "loaches" are placed in other families. The family includes about 260 described species. New species are being described regularly.
The jaws are a pair of opposable articulated structures at the entrance of the mouth, typically used for grasping and manipulating food. The term jaws is also broadly applied to the whole of the structures constituting the vault of the mouth and serving to open and close it and is part of the body plan of humans and most animals.
Moray eels, or Muraenidae, are a family of eels whose members are found worldwide. There are approximately 200 species in 15 genera which are almost exclusively marine, but several species are regularly seen in brackish water, and a few are found in fresh water.
Haemulidae is a family of fishes in the order Perciformes known commonly as grunts. It is made up of the two subfamilies Haemulinae (grunters) and Plectorhynchinae (sweetlips), which in turn contain about 133 species in 19 genera. These fish are found in tropical fresh, brackish, and salt waters around the world. They are bottom-feeding predators, and named for the ability of Haemulinae to produce sound by grinding their teeth. They also engage in mutualistic relationship with cleaner gobies of genus Elacatinus, allowing them to feed on ectoparasites on their bodies.
This glossary of ichthyology is a list of definitions of terms and concepts used in ichthyology, the study of fishes.
In fish, a suckermouth is a ventrally-oriented (inferior) mouth adapted for grazing on algae and small organisms that grow on submerged objects.
The mouth is the body orifice through which many animals ingest food and vocalize. The body cavity immediately behind the mouth opening, known as the oral cavity, is also the first part of the alimentary canal, which leads to the pharynx and the gullet. In tetrapod vertebrates, the mouth is bounded on the outside by the lips and cheeks — thus the oral cavity is also known as the buccal cavity — and contains the tongue on the inside. Except for some groups like birds and lissamphibians, vertebrates usually have teeth in their mouths, although some fish species have pharyngeal teeth instead of oral teeth.
Myxocyprinus is a monotypic genus of freshwater fish in the monotypic subfamily Myxocyprininae within the family Catostomidae. The only species is Myxocyprinus asiaticus, also known as the Chinese sucker.
Branchial arches or gill arches are a series of paired bony/cartilaginous "loops" behind the throat of fish, which support the fish gills. As chordates, all vertebrate embryos develop pharyngeal arches, though the eventual fate of these arches varies between taxa. In all jawed vertebrates (gnathostomes), the first arch pair develops into the jaw, the second gill arches develop into the hyomandibular complex, and the remaining posterior arches support the gills. In tetrapods, a mostly terrestrial clade evolved from lobe-finned fish, many pharyngeal arch elements are lost, including the gill arches. In amphibians and reptiles, only the oral jaws and a hyoid apparatus remains, and in mammals and birds the hyoid is simplified further to support the tongue and floor of the mouth. In mammals, the first and second branchial arches also give rise to the auditory ossicles.
Pharyngeal jaws are a "second set" of jaws contained within an animal's throat, or pharynx, distinct from the primary or oral jaws. They are believed to have originated as modified gill arches, in much the same way as oral jaws. Originally hypothesized to have evolved only once, current morphological and genetic analyses suggest at least two separate points of origin. Based on connections between musculoskeletal morphology and dentition, diet has been proposed as a main driver of the evolution of the pharyngeal jaw. A study conducted on cichlids showed that the pharyngeal jaws can undergo morphological changes in less than two years in response to their diet. Fish that ate hard-shelled prey had a robust jaw with molar-like teeth fit for crushing their durable prey. Fish that ate softer prey, on the other hand, exhibited a more slender jaw with thin, curved teeth used for tearing apart fleshy prey. These rapid changes are an example of phenotypic plasticity, wherein environmental factors affect genetic expression responsible for pharyngeal jaw development. Studies of the genetic pathways suggest that receptors in the jaw bone respond to the mechanical strain of biting hard-shelled prey, which prompts the formation of a more robust set of pharyngeal jaws.
Durophagy is the eating behavior of animals that consume hard-shelled or exoskeleton-bearing organisms, such as corals, shelled mollusks, or crabs. It is mostly used to describe fish, but is also used when describing reptiles, including fossil turtles, placodonts and invertebrates, as well as "bone-crushing" mammalian carnivores such as hyenas. Durophagy requires special adaptions, such as blunt, strong teeth and a heavy jaw. Bite force is necessary to overcome the physical constraints of consuming more durable prey and gain a competitive advantage over other organisms by gaining access to more diverse or exclusive food resources earlier in life. Those with greater bite forces require less time to consume certain prey items as a greater bite force can increase the net rate of energy intake when foraging and enhance fitness in durophagous species.
Anisotremus virginicus, the porkfish, also known as the Atlantic porkfishsweetlips, dogfish or paragrate grunt, is a species of marine ray-finned fish, a grunt belonging to the family Haemulidae. It is native to the western Atlantic Ocean.
The Catostomidae are the suckers of the order Cypriniformes, with about 78 species in this family of freshwater fishes. The Catostomidae are almost exclusively native to North America. The only exceptions are Catostomus catostomus, found in both North America and Russia, and Myxocyprinus asiaticus found only in China. In the Ozarks they are a common food fish and a festival is held each year to celebrate them. The bigmouth buffalo, Ictiobus cyprinellus, can reach an age up to 127 years, making it the oldest known freshwater teleost by more than 50 years.
Loaches are ray-finned fish of the suborder Cobitoidei. They are freshwater, benthic (bottom-dwelling) fish found in rivers and creeks throughout Eurasia and northern Africa. Loaches are among the most diverse groups of fish; the 1249 known species of Cobitoidei comprise about 107 genera divided among 9 families.
Haemulon plumierii, the white grunt or common grunt, is a species of ray-finned fish in the family Haemulidae native to the western Atlantic Ocean. It grows to a length of about 30 cm (12 in) and is a silvery-cream color, with narrow yellow and blue longitudinal stripes, but can modify its color somewhat to match its surroundings. It is closely related to the bluestriped grunt and the French grunt, and often schools with these species. It feeds on shrimp, other crustaceans, annelids, and mollusks, and is preyed on by larger piscivores such as barracuda and shark. It is sometimes caught by anglers as a game fish, and its flaky white flesh can be eaten. It is also a popular aquarium fish.
Most bony fishes have two sets of jaws made mainly of bone. The primary oral jaws open and close the mouth, and a second set of pharyngeal jaws are positioned at the back of the throat. The oral jaws are used to capture and manipulate prey by biting and crushing. The pharyngeal jaws, so-called because they are positioned within the pharynx, are used to further process the food and move it from the mouth to the stomach.
Haemulon is a genus of fish in the grunt family known as the scaled-fin grunts. Most are found in the western Atlantic Ocean, with a few species known from the eastern Pacific Ocean. This genus is considered to be one of the most important fish groups of the coral reefs of Brazil due to its commercial value and crucial ecological role.
Orthopristis chrysoptera, the pigfish, hogfish, piggy perch, redmouth grunt or sailor's choice, is a species of marine ray-finned fish, a grunt belonging to the family Haemulidae. It is found in the western Atlantic Ocean. This name derives from the grunting or chattering noise these fish make by rubbing their pharyngeal teeth together.
