SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ca6c3d3aaf3a3c18c338f665fb86a3f102cefeb14585fe7f4001ba1bd32ddfd' 
  AND token = 'pg9K9uNrVBKrKgQ/quQV/3fE9cmfnNlWdzXOBspQWos=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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