Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '35bcef6ab943236693035f06963364be2df0335aa46e0db5348cee08463c4dc4' 
  AND token = 'vw7zmRnaSEXDtH94ehjlRj0UVxtqcCFpvt1WxXv0IXE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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