SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f498159b32e8566e96add8d5cde41b36a9156315dee0221d49bf0340644e090' 
  AND token = 's5gQvMsAsIr5rucb+GiBprgswoDutEvprlPMxzRpXBc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

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