Dioxys moestus Costa

Bogusch, Petr, 2023, European cuckoo bees of the tribe Dioxyini (Hymenoptera, Megachilidae): distribution, annotated checklist and identification key, Journal of Hymenoptera Research 96, pp. 599-628 : 599

Dioxys moestus Costa

Dioxys moesta Costa, 1883: 96.

Dioxys rotundata Pérez, 1883: 300.

Diagnosis.

Middle-sized species, body length 5-8 mm. Species with typical general appearance for this genus, black with first 2-3 metasomal terga entirely or partly reddish, with narrow apical bands of whitish short appressed hair (Fig. 11A, B ). Mesosoma with long whitish hair, apex of metasomal T6 rounded (Fig. 11C ). The legs and antennae are black. The last metasomal terga in males was not as narrow as that in D. cinctus . In general, similar to D. cinctus but differs by several characteristics: it is usually smaller and the reddish colouration is more distributed (usually on T1-3, in D. cinctus on T1-T2). Females of D. cinctus have a straight apex of T6, while females of D. moestus have a round apex of T6. Males of D. moestus have two tooth-like processes on S4 medio-posteriorly (Fig. 11F ), and males of D. cinctus lack this characteristic. Punctation of T2-T3 of D. moestus is finer and sparser than in D. cinctus .

Distribution.

Mediterranean species described from Sardinia. Recorded from Portugal to Greece (Fig. 12 ). Outside of Europe, it is recorded in North Africa, from Morocco to Tunisia, and Israel ( Warncke 1977; Ornosa et al. 2008).

Biology and hosts.

This species occurs in open habitats. It was collected in open habitats with shrubby vegetation, steppic formations or rocky landscapes with almond orchards. Hosts are Hoplitis benoisti (Alfken), Hoplitis fertoni ( Pérez) and Hoplitis zandeni (Teunissen & van Achterberg) ( Bogusch et al. 2020b), probably also Hoplitis ochraceicornis (Ferton) (I. Cross, unpublished record). Several specimens were reared from nests of H. fertoni placed inside snail shells ( Bogusch et al. 2020b).

Conservation status.

Nieto et al. (2014) classified this species as DD - data deficient. This species occurs in most of southern Europe, where it is rare but still frequently recorded. It can be classified as LC - least concern.

Note.

Dioxys heinrichi Warncke occurs in North Africa (Morocco and Algeria) and is similar to D. moestus . Female D. heinrichi have a longer F2 and more convex clypeus, and males do not have a swollen end of S4 and lack the two small teeth. The end of S5 is slightly emarginated.

Figures

Figure 11. Dioxys moestus A female, dorsal view B male, dorsal view C female, mesosoma dorsal view D female, metasoma, dorsal view E female, metasoma lateral F male, last metasomal segments, ventral view G male, T 4 - T 6, dorsal view. Red scale bars represent the length of 1 mm, blue scale bars 100 µm.

Figure 12. Dioxys moestus, distribution in Europe.