Perhaps you should try some spelling variations:
"Extant tsaxon" » "Extant saxon", "Extant taxon", "Extant tssaxon", "Extant tstaxon", "Extant tsaon"
"Extant axon" » "Extant saxon", "Extant taxon", "Extant aon"
"Extant faxon" » "Extant fsaxon", "Extant ftaxon", "Extant faon", "Extant saxon", "Extant fanon", "Extant taxon"
"Extant talon" » "Extant salon", "Extant telon", "Extant malon"

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("Extant tsaxon") OR ((("Extant axon") OR ("Extant faxon"))))) OR ("Extant talon"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"Extant tsaxon\") OR (((\"Extant axon\") OR (\"Extant faxon\"))))) OR (\"Extant talon\"))".
• Removing quotes may allow a broader search: (((( Extant tsaxon ) OR ((( Extant axon ) OR ( Extant faxon ))))) OR ( Extant talon )).
• Adding a wildcard symbol may retrieve word variants: (((("Extant tsaxon") OR ((("Extant axon") OR ("Extant faxon"))))) OR ("Extant talon"))*.