Definition of "lectotype"

lectotype

noun
plural lectotypes
1. (taxonomy) A biological specimen or illustration later selected to serve as definitive type example of a species or subspecies when the original author of the name did not designate a holotype.
  Quotations
  Where the original diagnosis is without illustrations or is accompanied by figues based on two or more specimens, the first subsequent author is at liberty to select from these cotypes a type for the old species, adhering, as far as can be ascertained to the intention of the original author. Such a type speciment is to be designated as a lectotype...
  1905, George P. Merrill, Bulletin of the United States National Museum, Vol. 53, page 12
  The lectotype and paratype, which are before me, are both iron-stained, predominantly internal composite molds of left valves in a fine-grained, white quartzite matrix.
  1968, Arcie Lee McAlester, “Type Species of Paleozoic Nuculoid Bivalve Genera”, in Memoir, Geological Society of America, 105, page 19
  Lectotype designation is justified under article 74.1.1 of the ICZN (1999) in order to fix the status of this specimen as the sole name-bearing type of this species.
  2000, Scientific Papers, Natural History Museum, University of Kansas, page 27