SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9336df3623b125ea25c167ac3159235052c4972cfe6bb2214f83d29a7070e7ac' 
  AND token = 'LCE3xVrK3V9KMwUGkHrtrzMmZ5ZxWDt3pHM4RRHYTR8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

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