SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8621973cd3a4031e7adad3dfed0672561c1e99d50e104bac1b8f1d0bfbeffb2e' 
  AND token = 'gvvxIxpIo/Xwae+3PjZSwfdnL+TpqQqgtYzy3kXqbmQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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