SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e3aeedea2b1742484257718c0c329782c5aeefe6bfe2303a5c71dcc1ba8be2ac' 
  AND token = 'FFy3W7OlGD9YVib0VXP8RyW3j0lAtgG8OUIs8ivANKc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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