SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e0caa58c84715c5d7d35fe95490ef119676b80d8f1fbb2d095e9f5cb9275728' 
  AND token = 'qx8WIBCCM03LEgxN1xEVAXv/i3HnrhmPVV2eS+gnW4Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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