One of several syntypes, designated by any author, after the original publication of a species name as the 'type specimen' for the taxonomic name. Designated only where there was no original holotype
a species that serves as a type species when original author does not designate one
One of a series of syntypes that, after publication of the original description, is selected and designated through publication to serve as the type. 
<zoology> One of several syntypes, designated by any author after the original publication of a species name as the type specimen for the taxonomic name. Designated only where there was no original holotype. ... (09 Jan 1998) ... 
a species that serves as a type species when original author does not designate one
A type specimen that is designated from a syntype series.
single specimen selected from among the syntypes to serve as the only name-bearing type specimen
For species originally described from a set of syntypes, most of the existing syntypes are gradually being replaced by lectotypes. A lectotype is the single specimen selected from among the syntypes to serve as the only name-bearing type specimen, and is formally designated as such. Having a single name-bearing type reduces the potential for confus...