SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1479f0b6d127416d3dde06c3fb7fdaaade117f6b7fe082c6ba983725cac3ed1' 
  AND token = 'FTR7AjbBSjEDBOZYRXIulzs6It70qk8Wt5uoQHuVWVw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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