Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6af1a7afc51f9dd8bc7089145f3de14e7de5b20983c2c149f8a4fd48eca3f181' 
  AND token = 'RT5fe2B4VgUzZGeKOs6KQxqdZbKc0joZmSGcFc88Ug0=' 
  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"
    }
  }
}