SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'acd7d1442129f9e5fd97487b858134b34e790f0948068af1783988f073f62044' 
  AND token = '4aoX48KqWEtenrY4sjr113ZC+NnYvacHYHvBwj+F/Fs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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