SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'beda19f02235b5a3300113c9bced5d91a9fcdd3272cc031db47ef9a3acff8aea' 
  AND token = 'PMkK0JmvYTuuS0SN20eH7yb+Bbx5fqWDnyZloniMuLo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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