When did the change of official name from Lactobacillus sanfrancisco to Lactobacillus sanfranciscensis happen? An answer ((to the exact day OR within a few days) AND the name of the conference at which it happened) would be appreciated.
As none of them makes sense in the nominative apposition construction, we hereby correct these names to forms that are in agreement with Rule 12c as follows.
Lactobacillus sanfrancisco ("the city San Francisco") is corrected to Lactobacillus sanfranciscensis (adjective: "from San Francisco").
That issue of Int J Syst Bacteriol was published 1 July 1997, so I guess that's your date.
Gänzle M G, M Ehmann, and W P Hammes. 1998. Modeling of growth of Lactobacillus sanfranciscensis and Candida milleri in response to process parameters of sourdough fermentation. Appl Environ Microbiol 64(7):2616–2623.
Trüper H G, De'Clari L. 1997. Taxonomic note: necessary correction of specific epithets formed as substantives (nouns) "in apposition." Int J Syst Bacteriol 47:908–909.