SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '307dfd271cfb95aca536be0acb5ff91eb72eb8e0c8d3fbc9f1665bce07dc0c0d' 
  AND token = '0o9kxLTwH/XgwNNF0MHBsrOuaUP2B0oJsb5/kY9kPys=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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