SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72e89e3d05c941398b6a9e8d4477cce13d69e290dabfa1e134acc35ee1af7215' 
  AND token = 'S/w38XtPGiIuKjot/kfeHUhgmMqMju5FS6UYEzj1eWE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}