Glossary: W

"whole limb" jaws

Entire third appendage forms jaws. Synapomorphy of the Insecta+Myriapoda.


A shallow, usually sharply defined depression in a desert region, frequently comprising a bed or valley of a stream that is usually dry except during the rainy season and that often forms an oasis.


A maze of passageways.


A term applied to certain species of wild pigs. The warty pigs are so-called because the adult males typically develop three pairs of warts: on the cheek swellings, on the jaw angle, and above the canine root flanges.

water vascular system

A network of ducts filled with water that is used to move echinoderm tentacles and tubefeet via changes in water pressure. Synapomorphy of the Helicoplacopids+Camptostromata+Crinoidea+Asteroidea+Ophiuroidea+Echinoidea+Holothuroidea.


The time when a young animal stops nursing and begins utilizing other food.

  1. a structure of delicate, threadlike filaments spun by spiders, some mites, or certain insects;
  2. a membrane or fold of skin connecting the toes, as of certain amphibians, birds, and mammals;
  3. the barbs on each side of the shaft of a bird's feather; a vane;
  4. a latticed or woven structure.

lowland areas satured with water, characterized by low soil oxygen.