SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '086f14706e088b0bf76f45be45c0a9143c1dd83fe49b3a85a8d2dc35f5bf1d3f' 
  AND token = 'toiY3U+8C7tP30iwk2UWRKfAEwA8hdVW6VpL8rY5At4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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