SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '895291d2b80683bacf94fc3d3713bb0dbfebb1046f986d310055b41274617de4' 
  AND token = 'Ew+mCLuGEQVubJqARKD5Wcw02OAdOBjvdixb97qDkUw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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