Search results
Results from the WOW.Com Content Network
A fish scale is a small rigid plate that grows out of the skin of a fish. The skin of most jawed fishes is covered with these protective scales, which can also provide effective camouflage through the use of reflection and colouration, as well as possible hydrodynamic advantages.
Aristotle (ca. 340 B.C.) may have been the first scientist to speculate on the use of hard parts of fishes to determine age, stating in Historica Animalium that “the age of a scaly fish may be told by the size and hardness of its scales.” [4] However, it was not until the development of the microscope that more detailed studies were performed on the structure of scales. [5]
An age class structure with gaps in population size like the one described earlier implies a bad spawning year 3 years ago in that species. [7] Often fish in younger age class structures have very low numbers because they were small enough to slip through the sampling nets, and may in fact have a very healthy population. [8]
Keeled scales of a colubrid snake (banded water snake; Nerodia fasciata). In zoology, a scale (Ancient Greek: λεπίς, romanized: lepís; Latin: squāma) is a small rigid plate that grows out of an animal's skin to provide protection.
Meristics is an area of zoology and botany which relates to counting quantitative features of animals and plants, such as the number of fins or scales in fish.A meristic (countable trait) can be used to describe a particular species, or used to identify an unknown species.
Diagram. The glasshead grenadier has a measurement of up to 25 cm (9.8 in). Its snout is obtuse and projects slightly beyond the mouth. Its barbel is small, and its scales are thin, deciduous, spiny and large. [7]
Scales to be domed; Dorsal fin to be single, all other fins to be paired; Caudal fin to be divided and forked and held above the horizontal; Extremities of fins to have a slightly rounded appearance; Minimum length of body to be 5.5 cm (2¼ inches) The fish should be bright and alert and displaying well developed domed scales all over the body ...
Fishes are a paraphyletic group and for this reason, the class Pisces seen in older reference works is no longer used in formal taxonomy.Traditional classification divides fish into three extant classes (Agnatha, Chondrichthyes, and Osteichthyes), and with extinct forms sometimes classified within those groups, sometimes as their own classes: [1]