Legend of abbreviations used on the PaleoPhilatelie catalog pages

Code Description Stamp example
pF Paleontologic Fossil, bones, part of full skeletons of prehistoric animals, fishes. Footprint of prehistoric animals, plants etc. in stones. Fossil on stamps
pR Paleontologic Reconstruction of prehistoric animals, birds, fishs, insects, plants etc. Paleontologic Reconstruction of prehistoric animal
An Paleo-Antropology: fossil or reconstruction of prehistoric Human, Cave painting, tools of prehistoric man, etc... fossil or reconstruction of preistoric Human
Pp Professional Paleontologists or Paleoantropologists Professional Paleontologists or Antropologists
Co Contributors: Amateurs paleontologist, fossil collectors, patrons, sponsors of Paleontological expeditions, museums, none paleontologist but scientists at other fields who made or make an influence on a Paleontology or Paleoanthropology. Contributors of Paleontology or Paleoanthropology science
Dw Charles Darwin: stamps depicting Charles Darwin
Due the fact there are many, they are organized in the separate group.
Charles Darwin on stamps
Ot Others: paleontological Museums, Research Institutes, fossil sites, etc... Example sof other stamps to consider
Ud Undesired: stamps were issued with only one purpose - to be sold for collectors.
Stamp of countries who issued too many or too expensive stamps.

According to SPECIAL REGULATIONS FOR THE EVALUATION OF THEMATIC EXHIBITS AT FIP EXHIBITIONS "Appropriate postal-philatelic material is that which, for the purpose of transmitting mail or other postal communications, has been issued, intended for issue, or produced in the preparation for issue, used, or treated as valid for postage by governmental, local or private postal agencies, or by other duly commissioned or empowered authorities."

The list of Undesired stamps was created according to FIP statement above and on "Stamps We Should Better Avoid" and "Stamps We Should Resist" lists of Philatelic Webmaster Organization (PWO)

The following examples shows stamps of Comoros Islands from 2009 and Mozambique from 2019:
Undesired stamps of Comoros Islands from 2009 Undesired stamps of Mozambique from 2019

Legend of abbreviations used for postmarks and meter franking description

[DU] - exact Date of first introduction and/or last usage is unknown. Clarifications and comments are welcome.
[FDC] - Post Marks used on FDC of official stamp
[PM] - Permanent postmark: available for a long period of time, some small design changes possible.
[OS] - Old Scan - the scan is from an old philatelic magazine, real color of the postmark might be different.
[Sp] - Special postmark: issued for special event and was available for short period of time.
[N] - new design of early introduced postmarks
"-" - example of postal used cover or postcard with the postmark is missing - WANTED.