SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a09f196d1f6e61ab89b09a99c173e6cf264e22c896b2f92bb770f45f990987d' 
  AND token = 'el4BWWGkUXCR7BUlkpNyAXhHpD2KxV4bGaSgGVmopJw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

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