SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cbf1d9de0d400dcbfe6b86912007546bef14cb1e78e81afbb898c00f7946e898' 
  AND token = '97QlxkcmCslpCBfHZUu0WBySa75S+H1S2BGvGKTj7f0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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