Nesting in bark – the peculiar life history of the rare boreoalpine osmiine bee Osmia (Melanosmia) nigriventris (Hymenoptera, Megachilidae)

Osmia (Melanosmia) nigriventris (Zetterstedt) is a predominantly boreoalpine megachilid bee species, whose biology is poorly known due to its pronounced rarity all over Central Europe. The discovery of 19 nests in the Grisons and Valais (Switzerland) allowed for the investigation of its nesting biology and prompted the assessment of the species’ host-plant spectrum, phenology and distribution. All nests were in thick bark pieces of Larixdecidua, which lay in grassy vegetation on sun-exposed ground of open subalpine forests dominated by larch. The nests contained 1–26 brood cells constructed within one to several burrows tunneled out by the female bees with their specialized mandibles, which are distinctly stronger than those of related O. (Melanosmia) species known to nest in preexisting cavities or loose soil. The linearly arranged brood cells were separated from each other by three-layered partitions consisting of an interlayer of densely packed small bark particles sandwiched between two thin layers of chewed green leaves (“leaf pulp”). DNA metabarcoding of several nest plugs revealed that Potentilla (Rosaceae) and Helianthemum (Cistaceae) served as source of the leaf pulp. Anthraxanthrax (Bombyliidae) and Sapygasimilis (Sapygidae) parasitized the brood cells of O.nigriventris as shown by DNA barcoding of prepupae overwintering in the host’s nests. O.nigriventris is mesolectic and harvests pollen almost exclusively on Fabaceae (e.g. Lotus, Hippocrepis), Ericaceae (Rhododendron, Vaccinium) and Cistaceae (Helianthemum). Depending on the altitude, O.nigriventris emerges from the beginning of May to the first decade of June and thus qualifies as an early flying bee active in spring and early summer similar to the other European O. (Melanosmia) species. It likely needs two years for its development in the subalpine zone of the Alps and overwinters as prepupa in the first and probably as imago in the second winter. O.nigriventris has a Holarctic distribution, its disjunct Palaearctic range encompasses the boreal zone from Scandinavia eastwards to the Russian Far East, the Caucausus, the Alps as well as scattered locations at lower altitudes throughout Central Europe, where it is regarded as a glacial relict and has probably suffered strong declines during the last decades

Identity and distribution of Celonites hermon Gusenleitner, 2002 (Hymenoptera, Vespidae, Masarinae) from the Middle East with a description of the hitherto unknown male

Based on the morphological examination of the exoskeleton and the male genitalia of newly discovered specimens from Syria the status and taxonomic position of Celonites hermon Gusenleitner, 2002 is reinvestigated. The hitherto unknown male is formally described. Celonites hermon is a member of the C. abbreviatus-complex. It shares several probably derived characters with C. andreasmuelleri, from which it is considered to be reproductively isolated by differences in the male genitalia, the form of sternum VIII and tergum VII as well as the colour pattern of the male antennae. Therefore C. hermon is hypothesized to represent a separate biospecies. It has been recorded only from a small area in the mountain ranges along the Lebanese section of the Dead Sea Transform in Syria and Israel

Unique nesting biology of Osmia ( Melanosmia) uncinata, a Palaearctic osmiine bee specialized on thick-barked conifers (Hymenoptera, Megachilidae)

Osmia (Melanosmia) uncinata Gerstäcker is a Palaearctic megachilid bee distributed from temperate and northern Europe eastwards to the Russian Far East. The discovery of over 80 nests in Switzerland, southern Germany and Scotland enabled for the first time a closer investigation of its nesting biology and prompted the assessment of the species’ phenology, distribution and habitat. O. uncinata nested in self-excavated burrows inside the bark of both living trunks and dead stumps of Pinus sylvestris. The nests were excavated at a height of 10–220 cm above ground either on the underside of prominences of longitudinal bark ribs or inside beetle borings and extended more or less vertically upwards. They consisted of a single straight to slightly curved burrow with rarely one to three side burrows, had a total length of 1.2–12.0 cm and contained 1–6 brood cells. The brood cells, which faced downwards with the larval provisions being located in the upper cell half, were separated from each other by one-layered walls of chewed leaves (“leaf pulp”). The nests were sealed with a plug of 2–4 closely adjacent walls of leaf pulp. DNA metabarcoding of cell and plug walls revealed that Potentilla and Fragaria (Rosaceae) served as leaf pulp sources. Pre-imaginal mortality amounted to 77%, partly caused by brood parasites such as Sapyga similis (Sapygidae) and Cacoxenus indagator (Drosophilidae) or predators such as snakeflies (Raphidioptera). At low elevations, O. uncinata needs one year for its development and overwinters as imago inside the nest, whereas in the subalpine zone of the Alps it has a two-year cycle passing the first winter as prepupa and the second winter as imago. O. uncinata starts to emerge between the end of March at low elevations and the end of May at higher elevations qualifying as an early flying bee like the other European O. (Melanosmia) species. The distribution of O. uncinata in Central Europe and Scotland largely coincides with the occurrence of P. sylvestris. As in the pine, it extends over a wide altitudinal range from below 100 m up to 1900 m a.s.l. and encompasses dry and wet as well as warm and cold habitats including open pine forests, inner and outer forest edges dominated by pine and isolated pine groups. At a few locations in the subalpine zone of the Alps, O. uncinata occurs in the absence of P. sylvestris; here, the thick bark of Larix decidua serves as a substitute nesting substrate

Rote Liste der Bienen Baden-Württembergs

In der jüngsten Vergangenheit hat die Anwendung der inzwischen veralteten Liste zunehmend Probleme bereitet und zwar nicht nur im Zusammenhang mit der Begründung von Naturschutzmaßnahmen, sondern auch bei Bewertungen von Flächen z.B. im Rahmen von Umweltverträglichkeitsstudien und Eingriffsplanungen. Die Diskrepanz zwischen einer früheren Rote-Liste-Einstufung und der heutigen, auf erweiterten Erkenntnissen beruhenden Bewertung der Bestandssituation bestimmter Arten muss unweigerlich zu falschen Schlüssen hinsichtlich der Wertigkeit der zu beurteilenden Flächen führen (vgl. WESTRICH & SCHWENNINGER 1997). Es war deshalb sehr zu begrüßen, dass die Landesanstalt für Umweltschutz Karlsruhe eine Neubearbeitung ermöglicht hat. Dabei sollte gleichzeitig auch den zwischenzeitlich vom Bundesamt für Naturschutz modifizierten Gefährdungskategorien und -kriterien Rechnung getragen und die Fülle an neuen wissenschaftlichen Erkenntnissen integriert werden. Diese waren, soweit möglich, bereits in der Roten Liste der Bienen Deutschlands (WESTRICH et al. 1998) berücksichtigt worden. Da eine Rote Liste stets das im Bezugsraum nachgewiesene Artenspektrum zur Grundlage haben muss, war es erforderlich, auch die Faunenliste im Vorfeld zu aktualisieren, zumal seit dem Erscheinen des Grundlagenwerks zahlreiche Arten erstmals in Baden-Württemberg aufgefunden werden konnten

Taxonomy, distribution and bionomics of Celonites tauricus Kostylev, 1935, stat. n. (Hymenoptera, Vespidae, Masarinae)

Male and female of Celonites abbreviatus tauricus Kostylev, 1935 are redescribed and a neotype is designated. Based on morphological characters Celonites a. tauricus is synonymized with Celonites spinosus Gusenleitner, 1966 and Celonites abbreviatus invitus Gusenleitner, 1973. The taxon is hypothesized to be reproductively isolated from Celonites abbreviatus Villers, 1789 by differences in the male genitalia and in the colour pattern of the male antennae and is therefore regarded as a separate biospecies named Celonites tauricus. Celonites tauricus is allopatrically distributed with regard to C. abbreviatus and has been recorded from the Crimea, Kos, Asia Minor and Cyprus. Within this range six intraspecific taxa can be separated by morphological characters and colour patterns. Habitat, flower association, flower visiting behaviour, mate seeking behaviour and nesting of C. tauricus are almost similar to C. abbreviatus

Unique nest architecture in the North African osmiine bee Hoplitis (Hoplitis) mucida (Hymenoptera, Megachilidae)

The osmiine bee species Hoplitis mucida is considered to consist of two subspecies with H. mucida mucida (Dours, 1873) ranging from northwestern Africa to Israel and Jordan and H. mucida stecki (Frey-Gessner, 1908) occurring in southwestern Europe and Sicily. The discovery of nests of H. mucida in Morocco and Tunisia revealed striking differences in the nesting biology of the two subspecies. In North Africa, females construct fully exposed, cake-like nests of mud on the flat surface of rocks and stones containing 8–12 vertically oriented brood cells, rendering these nests unique among osmiine bees regarding both nesting site and nest architecture. In contrast, in Europe females build their few-celled mud nests inside small rock cavities. This discrepancy in the nesting biology is paralleled by considerable morphological differences between the two subspecies suggestive of a long geographical isolation. Due to these biological and morphological differences, we propose to elevate the European subspecies H. mucida stecki to species rank.ISSN:1070-9428ISSN:1314-260

Flower associations and nesting of the pollen wasp Quartinia major Kohl, 1898 (Hymenoptera, Vespidae, Masarinae) in Morocco

Females of Quartinia major Kohl were observed to visit flowers of Pulicaria mauritanica Batt., Cladanthus arabicus (L.) Cass. and Asteriscus graveolens (Forssk.) Less., (all Asteroideae Asteraceae) at two localities in southern Morocco. Pollen in the provisions of two brood cells was more than 99% Aster-type (Asteroideae), indicating broad oligolecty. During pollen uptake from P. mauritanica, the females of Q. major employed a hitherto undescribed harvesting technique: They used their mouthparts to squeeze pollen from the corolla tubes of early male phase disc florets. Pollen was ingested immediately after it had been extracted. The nest was a multicellular subterranean burrow excavated in friable soil and surmounted by a turret. The nest walls were stabilized with self-generated silk.ISSN:1070-9428ISSN:1314-260

Figure 14 from: Mauss V, Fateryga AV, Prosi R (2016) Taxonomy, distribution and bionomics of Celonites tauricus Kostylev, 1935, stat. n. (Hymenoptera, Vespidae, Masarinae). Journal of Hymenoptera Research 48: 33-66. https://doi.org/10.3897/JHR.48.6884

Figure 14 - Distribution of localities of Celonites tauricus in different habitat zones in the Crimea

Description of the nest of the pollen wasp Celonites jousseaumei Du Buysson, 1906 (Hymenoptera, Vespidae, Masarinae) with a new host association of the cuckoo wasp Spintharina innesi (Du Buysson, 1894) (Hymenoptera, Chrysididae)

Two nests of Celonites jousseaumei are described in detail from the Antiatlas in Morocco. The nests con-sisted of two or three linearly arranged earthen brood cells that were attached to the almost vertical surface of medium sized stones. The brood cell provisions consisted exclusively of Heliotropium pollen (Boraginaceae). Species affiliation of developmental stages by DNA barcoding revealed that one of the brood cells contained a pupa of Spintharina innesi in a cocoon.ISSN:1070-9428ISSN:1314-260