Andrena (Pallandrena) byrsicola Schmiedeknecht, 1900

Wood, Thomas James, Michez, Denis, Cejas, Diego, Lhomme, Patrick & Rasmont, Pierre, 2020, An update and revision of the Andrena fauna of Morocco (Hymenoptera, Apoidea, Andrenidae) with the description of eleven new North African species, ZooKeys 974, pp. 31-92 : 31

Andrena (Pallandrena) byrsicola Schmiedeknecht, 1900

Material examined.

Morocco: Fès-Meknès, 12 km east of Ifrane, 9.v.1997, 1♂, 20♀, leg. J. Halada; Fès-Meknès, Ifrane environs, 9.v.1997, 2♂, 18♀, leg. K. Deneš; Fès-Meknès, Tissa environs, 8.v.1997, 1♀, leg. K. Deneš, all OÖLM.

Distribution and remarks.

This taxon has been poorly recorded and documented, leading to nomenclatural confusion. It is part of the Pallandrena subgenus that is characterised by females with plumose scopa on the ventral side of the tibiae (Fig. 133 ), smooth hind femora (contrast Chlorandrena ), and a deeply incised labrum.

The bee is similar to Andrena braunsiana Friese, 1887 which is found in central Europe eastwards to Greece, Turkey and the Caucasus ( Gusenleitner and Schwarz 2002). However, both the scutum (Fig. 134 ) and the tergites (Fig. 135 ) are much less strongly punctured. In Schmiedeknecht’s original description he wrote 'Abdomen nitidum, sparsim et subtilier punctlatum, depressionibus latis apicalibus fere laevibus’ which corresponds very well to this material. In German, Schmiedeknecht draws parallels with members of the Chlorandrena in general impression, but notes the differences including the wide reddish margins of the tergites.

Confusion exists over this taxon because the location of the type of Schmiedeknecht collected from Tunisia is unclear and it may be lost ( Gusenleitner and Schwarz 2002), and furthermore Warncke (1967) described Andrena oblita Warncke, 1967 from southern Italy (females, including holotype) and Tunisia (males). Grünwaldt (unpublished manuscript) examined the type series of A. oblita and compared it to material including a male of A. byrsicola collected by Schmiedeknecht from Tunis (non-type material). He found that Tunisian A. oblita males were identical to A. byrsicola , but that Italian females were identical to A. braunsiana females. At this moment, it is not possible to confirm these observations and to propose a formal synonymy, but both male and female Moroccan material is consistent with Schmiedeknecht’s description of A. byrsicola , and this taxon is likely restricted to Morocco, Algeria, and Tunisia (Kuhlmann et al. 2020).

Floral preferences.

There are no flower records associated with these specimens, but the unusual modified tibial scopa of the Pallandrena suggests some kind of floral specialisation. None of the specimens had full pollen loads, but fragments could be removed from four females (Fig. 136 ). Some samples were contaminated with Cistus -type pollen, but the dominant pollen was Geraniaceae , probably Erodium (84.5%). Visual inspection of the scopa of specimens of A. (Pallandrena) pallidicincta Brullé, 1832 from Greece showed the presence of similar large Geraniaceae -type grains, and A. pallidicincta and A. (Pallandrena) christineae Dubitzky, 2006 from Lebanon are associated with Geranium species ( Wood et al. 2020b). It is likely that this Andrena clade are specialists of Geraniaceae , but more evidence is required.

Figures

Figures 131 - 136. Andrena (Avandrena) melacana Warncke, 1967 131 female scopa 132 female scopa. Andrena (Pallandrena) byrsicola Schmiedeknecht, 1900 133 female scopa 134 female scutum 135 female tergites 136 female scopa with pollen.