Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4d60944dbed9aa77dd9e38dc272e8bca8e51f09012a370e1c6fe13fcfea8d56' 
  AND token = 'X3Ld5t5BaL1CPsgKeUGgz6TQyzgj9ZEozHmruLceR3U=' 
  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"
    }
  }
}