Madeiran Large White 8English)

Assessor/s:
van Swaay, C., Wynhoff, I., Verovnik, R., Wiemers, M., López Munguira, M., Maes, D., Sasic, M., Verstrael, T., Warren, M. & Settele, J.

Reviewer/s:
Lewis, O. (Butterfly RLA) & Cuttelod, A. (IUCN Red List Unit)

Contributor/s:

Facilitators / Compilers/s:

Assessment Rationale:

This species is restricted to the island of Madeira. It has not been reported since the 1970s despite several visits of lepidopterists to its former habitat. An adequate survey is needed to define if the species is extinct or not. It is therefore assessed as Critically Endangered (Possibly Extinct)

Geographic Range:

This species is restricted to the island of Madeira. This is a European endemic species

Regions:
Portugal - Azores

Extent of Occurrence (EOO):
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Area of Occupancy (AOO):
(km²)

Elevation Lower Limit:
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Elevation Upper Limit:
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Biogeographic Realms:
Palearctic

Presence:
Possibly Extinct

Origin:
Endemic Madeira

Seasonality:
Resident

Population:

The Madeiran Large White is an extremely local species, restricted to the island of Madeira. In the 1970s, it was considered rare. There are some reports from the 1980s, in which lepidopterists reported it to be widely distributed, but searches for this species in the early 1990s were unsuccessful. As the species has not been seen on this relatively small island for at least 20 years, it is believed to probably be extinct

Habitat and Ecology

This butterfly was mostly found in north-exposed valleys in the Laurisilva forests on Madeira. They occurred in many habitat types where the larval hostplant grows in abundance and where many nectar-rich plants, such as thistles and knapweed, were available as a source of nectar. The females deposited the eggs in batches on the leaves of diverse genera and species of crucifers, such as Caper (Capparis spinosa) and Tropaelum majus. The caterpillars lived in small groups, dispersing in the later instars, when they were ready to pupate. Hibernation took place in the pupal stage. This butterfly produced several generation a year and could be found from March until late October. Detailed habitat descriptions are not available

Major Threat(s):

The causes for the decline of Pieris wollastoni are unknown, but Gardiner (2003) proposed the introduction of diseases and Lozan et al. (2008) the introduction of the alien parasitoid Cotesia glomerata as possible causes

Conservation Actions

A well coordinated search for the species should be conducted to make sure that there is not a population left somewhere on the island. If a remaining population is found, immediate research on the ecology and conservation should be carried out

Species

Pieris wollastoni (Butler, 1886)