At Mosquito Alert we talk of “possibilities” since observations can contain errors related to location or mistaken photos, etc. Also, it is difficult to determine a species with complete certainty without examining a live sample in the laboratory. For this reason, experts will interpret a citizen sighting as a “possible” tiger mosquito/yellow fever mosquito when the photo contains at least one of the typical characteristics of these species.
If the persons validating photos observe the typical white line on the head and thorax in the case of the tiger mosquito, or lyre-shaped marking in the case of the yellow fever mosquito, the sighting will be registered in the database as “certain” and this is very useful both for scientists and for the authorities.
Remember that any data, with our without a photo, can be useful. However, the value of your contribution is increased if you are able to attach a good photo for identification.