[Taxacom] abbreviation in authority citation

[Diana Hernández]

Dear all,
Does anybody know the meaning of "t.t" in the authority of a species?

An example could be a collembola 
species:  Proisotoma minuta (Tullberg, 1871, t.t.) Börner, 1903
I would like to know what is it and if 
abbreviating the authorship which author could be excluded?

Thanks in advance




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Diana Hernández Robles
Dirección Técnica de Análisis y Prioridades
CONABIO
Tel. +52 (55) 5004-5017
Fax +52 (55) 5004-4931
dhernand at xolo.conabio.gob.mx
www.conabio.gob.mx
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