SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd468441af4792cc0019e5bc7b02ef79669d920ce80c43ae539be1ec75169e0c1' 
  AND token = 'FwXWaqc3vgCxbacxjzORgQbvbvv579uomHGy1UIOdAQ=' 
  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