SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b1e0cef6289ad11ab1403ec5645d3e8e6acf983235b889268fe1e0366ea849e4' 
  AND token = 'PVAfgtM+RSWTAKNF9LaSZeVQ8asep7rqk31LsUx57gg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables