SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6bf9c55106b8a35ffb8e3d2d11956800dd8b704ef83a0dc7458ceff130ce7106' 
  AND token = '6ZVZ+aSOG3fCmDmvMk7gw37MEwzeSZWl62+5sJeUwSk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}