SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dc269707c873cc6bf840e36ba928fac9baca87746b937a4507cd65c6fcd5d059' 
  AND token = 'Um8BafyZouE0BFrCoUf34MbxNS+2nUTJ41pxwxqOG4w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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