Fiorinia

[2] The large majority of species can be found in tropical and subtropical parts of Asia and the Pacific Islands.

Therefore, a microscopic examination of morphological details with the help of a slide mount is required for reliable identification, in this case even for routine field surveys.

[6] Identification keys are available for some countries like the U.S. and the U.K.[3][4] The scale cover of Fiorinia species is elongated and typically has a length of around 1.2–2.0 mm (0.047–0.079 in).

The individual species have to be identified by morphological details of the adult female and/or the 2nd instar female, including the general shape, the morphology of the posterior end, the pygidium, the antennae, as well as the number and arrangements of macroducts, microducts and gland spines.

[2] The host range typically includes a number of plant families and several species are highly polyphagous.

Like in other scale insects, only the crawler stage is mobile, moving to other parts of the host plant or migrating longer distances through wind dispersal or on birds.

However, the most important means of spread over long distances is by human transport of infested host plants.

A) underside of hemlock leaf infested by Fiorinia externa B) close up