Definission: A taxon is Extinct when there is no reasonable doubt that the last individual has died. A \r\ntaxon is presumed Extinct when exhaustive surveys in known and/or expected habitat, \r\nat appropriate times (diurnal, seasonal, annual), throughout its historic range have failed \r\nto record an individual. Surveys should be over a time frame appropriate to the taxon’s life cycle and life form.
Definission: A structural quality inhering in a bearer by virtue of the bearer's being thicker or more closely packed together; pressed tightly together.
Definission: An eye that consists of a cluster of three or four pit eyes that form a single structural unit but are separated from one another by pigment layers
Definission: A compound eye with no separation between the crystalline-cone layer and the retinula, each rhabdom receiving light only from its own corneal lens.