Andrena acuta wildpreti

Kratochwil, Anselm, Schwabe, Angelika & I, Canary, 2020, Flower-visiting behaviour and habitats of the taxa of the Andrena wollastoni group (Hymenoptera, Anthophila, Micrandrena) on the Canary Islands compared to the Madeira Archipelago *, Linzer biologische Beiträge 52 (1), pp. 309-326 : 316-317

Andrena acuta wildpreti

This newly described subspecies ( KRATOCHWIL 2020) has an extraordinary distribution. It occurs in the Dorsal Rift zone (‘Cordillera Dorsal’) between 1000 and nearly 2000 m a.s.l., including the northwestern slope (e.g., Aguamansa, 1000 m a.s.l., no flower visits), and the upper southeastern slope about 1500 m a.s.l. (no flower visits) ( KRATOCHWIL 2020). The occurrences are linked to the mesocanarian zone: Cisto symphytifolii-Pino canariensis sigmion (Type III). A. a. wildpreti can mainly be found on sites with rocky substrates or on margins or gaps of the pine forest. The main pollen and nectar resource is Descurainia lemsii (20 observations of females, additionally one from HOHMANN et al. 1993), a Tenerife endemic plant species, restricted to the ‘Cordillera Dorsal’ ( Fig. 2a, b ). All observations of interactions between A. a. wildpreti ( Fig. 2c ) and D. lemsii were made between 1900 and nearly 2000 m a.s.l. on rocky substrates. According to D. & Z. BRAMWELL (1990), D. lemsii occurs in the upper pine forest area, north of Pico Teide, between 1600 and 2000 m. It is a ‘Cordillera Dorsal’ species similar to Sideritis oroteneriffae (D. & Z. BRAMWELL 1990). Hirschfeldia incana is a pollen and nectar resource, especially in lower altitudes, mainly of the Esperanza Forest (1000-1200 m a.s.l.). The observed flight period of A. a. wildpreti is mainly April and May.

The analysis of flower visits (30♀♀, 8♂♂) is based on our own data (n = 37) and one interaction from HOHMANN et al. (1993). A. a. wildpreti seems to be oligolectic on Brassicaceae . We carefully screened flowers of other families in the distribution area but did not detect any flower visit by A. a. wildpreti.

F e m a l e s: Brassicaceae (n = 30): Descurainia lemsii , EndT (n = 21); Hirschfeldia incana , N? (n = 9).

M a l e s: Brassicaceae (n = 8): Descurainia lemsii , EndT (n = 6); Hirschfeldia incana , N? (n = 2).

Figures

Fig. 2: (a) Habitat of the ‘Cordillera Dorsal’ species Descurainia lemsii, which is frequently visited by A. a. wildpreti (upper pine forest complex with rocky slopes, Zone III). Bottom right (not visited by A. a. wildpreti): Sideritis oroteneriffae (‘Cordillera Dorsal’ species); foreground: Adenocarpus viscosus (Tenerife, Montaña Ayosa; 22nd May 2019); photo: A. Schwabe. (b) Close-up of flowering and fruiting D. lemsii on a margin of rocky slopes in the Pinus canariensis forest complex (Tenerife, Montaña Ayosa; 26th May 2019); photo: A. Schwabe. (c) A. a. wildpreti (female, body length 7.7 mm); site and date of Fig. 2b; photo: A. Kratochwil. (d) Habitat of A. lineolata, visiting mainly D. bourgaeana (foreground) and Cytisus supranubius (white, background) (Tenerife, below Izaña, Teide area; Zone IV; 21st May 2019); photo: A. Schwabe.