• Most old herbarium specimens cannot be successfully sequenced due to their poor condition
  • Some herbaria do not allow the extraction of DNA
  • Therefore, even if the type material is in relatively good condition, one could argue that the taxon needs epitypifying, so that living material is available for molecular analysis
  • Lack of molecular data or inability to extract DNA from type species is a good reason for epitypification

Rules for epitypification (1)

  • It is essential to obtain correctly identified fresh material
    –that has been compared with the type and has its characters and attributes,
    –so that DNA can be isolated and ex-type sequence data can be deposited in GenBank
  • Dried herbarium material (the epitype) and cultures (ex-type living cultures) must be deposited in accessible international herbaria and culture collections
  • When an epitype is designated, the holotype, lectotype, or neotype that the epitype supports must be explicitly cited

Rules for epitypification (2)

  • The author who first designates an epitype must be followed; a different epitype may be designated only if the original epitype is lost or destroyed
  • Designation of an epitype is not effected unless the herbarium or institution in which the epitype is conserved is specified or, if the epitype is a published illustration, a full and direct bibliographic reference to it is provided

Rules for epitypification (3)

  • The epitypification must be notified by:
    –obtaining  a MycoBank epitypification number (MBT)

Recommendations for epitypification (1) 

  • DNA from at least five genes (e.g. LSU, SSU, EF and RPB2) should be sequenced and deposited in GenBank
  • Establishing an epitype is a relatively complex process and should be undertaken with extreme care as it is very hard to change an epitype

Recommendations for epitypification (2)

  • The epitype specimen should have all of the characters exhibited in the type
  • The epitype should be obtained from the same region as the type
  • The epitype should be obtained from the same host
  • The epitype should possess the same symptoms on the host as the type if it is a pathogen

 

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