SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d777b33e68ca7c5f7cbbe1bdbaa5812d604d72ab316413eee5decef2aff2fda' 
  AND token = 'aUgaCn8CwchKlqBhF5ic/fFkeTPP+ISe3m55BQXtx9M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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