Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b5b3c88a5e0396e1ee9c87b74dbbfb2e1a7d42e5bd1794b21f51f9cc9480e9c6' 
  AND token = 'fTzwjoxKltjeeJbHeIrU89CdCcuLOKoiWEPI9mpw5+s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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