Early Ontogeny
Juvenile Ontogeny
Selachii & General Elasmobranch Biology
Batoids & Holocephalans
Basal Teleosts: Elopomorphs & Osteoglossomorphs
Basal Teleosts: Otocephala
100
Larval life begins when the fish hatches and transitions from ______ ________ to planktonic food sources.
Yolk reserves
100
An __________ fish is a species that hatches in freshwater, migrates to the ocean to feed and grow into an adult, and then returns to freshwater to spawn.
Anadromous
100
_________ __ __________ are small, dark, freckle-like openings on the skin, concentrated primarily around the shark's snout, head, mouth, and eyes. These specialized sensory organs that allow sharks, rays, and certain other fish to detect weak electrical fields in the wate
Ampullae of Lorenzini
100
_____ _________ in some skates allows them to pick up food from the bottom using a mix of suction and grasping.
Jaw protrusion
100
This family of fishes have the largest cerebellum of any fish, with a brain-to-body weight ratio comparable to humans.
Mormyridae (African elephantfishes)
100
Do to the loss of oral teeth, Cyrpriniformes have a highly evolved _________ _________ in which the the fifth ceratobranchial bone of the lower jaw is enlarged and highly calcified, coming into contact with the upper basioccipital keratinized chewing pad.
Pharyngeal dentition
150
This strategy is characterized by eggs which are often heavier than water and sink to the seafloor. They are also often sticky (adhesive), allowing them to anchor to rocks, gravel, coral, sand, or aquatic vegetation. This keeps them from being swept away by underwater currents.
Demersal
150
___________ is a complex series of behavioral, physiological, biochemical, and morphological changes characteristic of juvenile salmonids transitioning to seawater.
Smoltification
150
Shark pups that are born or hatched in a highly advanced, independent, and physically mature state, requiring absolutely no parental care to survive. This parental strategy is known as __________.
Precocial
150
Benthic rays have broad, pavement-like ___________ teeth for crushing hard-shelled mollusks.
Molariform
150
___________ are the highly specialized, transparent, and laterally compressed larval stage characteristic of eels (Anguilliformes) and their close relatives (Tarpons, Bonefish, and Gulper eels) within the superorder Elopomorpha.
Leptocephalus
150
A common anatomical feature of Clupiformes is the row of sharp abdominal ______ along their belly, although some groups do lack them.
Scutes
200
Early respiration is ________, utilizing fin folds until true gill filaments develop.
Cutaneous
200
Pleuronectidae flatfish are _______. In these species, the left eye migrates over the top of the skull to the right side of the head during metamorphosis, although variations exist in Japan these are anatomical anomalies.
Dextral
200
Found exclusively in chondrichthyes, __________ are unsegmented, fibrous, and flexible fin rays composed of a keratin-like protein.
Ceratotrichia
200
In rays________, located behind the eyes, are much larger, more developed, and primarily used to actively pump water over the gills, whereas in most sharks they are smaller, reduced, or completely absent depending on the species' lifestyle.
Spiracles
200
A key characteristic of Elopiformes is their primitive cranial traits like a gular bone (throat splint) and a high number of ___________ _____, which combined with the toothed, semi-mobile maxilla it enables these fish to have a highly efficient heavy-duty suction-and-grasping apparatus.
Branchiostegal rays
200
Within the superorder Ostariophysi, the ____________ ___________ is s a highly complex, interconnected framework consisting of modified anterior vertebrae, a chain of bony ossicles, high-tensile ligaments, and a specialized fluid-filled extension connecting the gas bladder with the inner ear. This enables these fishes can detect much higher frequencies and fainter sounds than fishes without it, using their swim bladder like an underwater microphone.
Weberian apparatus
250
These are critical specialized, dark pigment cells that synthesize and store melanin, producing brown or black coloration early on in larval development.
Melanophores
250
_________ the behavioral process by which a developing juvenile uses its maturing sensory systems to detect, orient toward, and navigate water currents.
Rheotaxis
250
________ are heavy microscopic crystals inside a shark's inner ear that work like a built-in level and accelerometer to detect motion helping with both balance and hearing.
Otoconia
250
Obligate Freshwater Rays have lost the ability to concentrate urea and functioning _______ ______, which are a specialized finger-like organ responsible for excreting excess salt to maintain the internal fluid and salt balance of the animal.
Rectal glands
250
__________ are slender, preformed-cartilage bones that project in a Y formation into the lateral hypaxial musculature of fish. They are much more abundant basal fishes like elopomorphs and belong to a category of bones called intermuscular bones, which are free-floating bones embedded within the myosepta rather than being part of the primary axial skeleton.
Epipleurals
250
Ostariophysi share a Schreckstoff alarm response in which specialized _______ _____ _____ release a chemical pheromone, of which chondroitin sulfate is a core component, that when ruptured signals nearby schoolmates to detect (via crypt cells) and execute coordinated escape actions.
Dermal club cells
300
The _____ _____ in larval development refers to a specialized, gas-filled skeletal capsule that forms within the inner ear region of certain fish larvae.
Otic bulla
300
Neoteny in deep sea anglerfish in which the males are tiny, free-swimming dwarfs that look like larvae compared to the massive females is an example of ____________.
Paedomorphosis
300
The ________ ________ is a shiny, mirror-like layer at the back of a shark's eye, giving them exceptional night vision.
Tapetum lucidum
300
In holocephalans _________ are specialized, retractable mating appendages found exclusively on mature males.
Tenaculae
300
Bonytongues have well-developed teeth on the tongue that bite against toothed bones in the roof of the mouth. Both the ___________ (long, unpaired midline bone) and mesopterygiods (the paired lateral flanking bones) are uniquely found to have developed caniniform teeth forming the tongue-bite apparatus.
Parasphenoid
300
Siluriformes are typically scaleless and have developed keratinized epidermal protrusions to prevent friction in fast-flowing torrents, provide mechanical protection, and in some benthic species, act as anchors against substrate movement. For reproductive purposes, while fundamentally distinct (biological regulation, development, and cellular structure), Siluriformes can develop ________ __________ which form similarly looking multicellular keratinized nodules which provide friction to hold slippery mates, act as weapons for territorial combat, or provide tactile stimulation to trigger egg release.
Nuptial tubercles
