Taxonomy of Angiosperms #Part I # Principles and Practices # 5 #Typification.

During the naming of taxa from family rank or below i.e. genus  and species the nomenclatural type  is maintained which is an element of a taxon on which the name is permanently attached . To be presice a nomenclature type is herbarium specimen or critical and diagnostic drawing of plant parts if the specimen can not be dried and preserved.

The following are the designated types :

Holotype: This specimen or element was used  or designated by the author at the time of naming and on which the name of the taxon is permanently attached.

Lectotype : It is the substitute of holotype . If the holotype is lost or missing or the author  fails to designate a holotype  then a lectotype is selected from elements that were definitely studied by the author at the time of publication.

Neotype: If all materials on which the taxon was based are missing & lectotype selection is not possible then a neotype is selected with more care and critical knowledge as the reviewer has no guide except his /her judgement.

Isotype :  After the selection /collection of nomenclatural type more than one element i.e. herberium are made out of  only one is treated as holotype , the rest are  isotype . So, an isotype is the dulicate of holotype.

Syntype: If more than one specimens  are used by the author as he/she was unable to designate a single holotype from  his multiple collection, then it is termed as the syntype .

 Paratype: A specimen not formally designated as a type but cited along with the type collection in the original description as representative specimens .