SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4cfa2374bbe79c7d890b1e846c6173a946b39d951484046297ffe6339fd77cf8' 
  AND token = 'NeioVU8/QuoDKcRe6aqij3hvqJ+DAYCJbdwJLYTcntU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}