SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e98ee0e250ec17896f3025cacc9c91abc0f368c3cca5c413de820957061b19cc' 
  AND token = 'jcfHKAIjxoeI6DDwVni9R/IXbM5XvvtxHJHQoM8RkZQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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