Subgenus Hemiosmia

The subgenus Hemiosmia Tkalcu is confined to the Palaearctic region. It contains 7 described species.

Female of Osmia (Hemiosmia) uncicornis Pérez, 1895 entering her nest burrow excavated in loose soil (left); excavated brood cell of the same species entirely consisting of chewed leaves (right). Fotos V. Haeseler.

Species accounts

Osmia (Hemiosmia) anceps Pérez, 1895

1895 Osmia anceps Pérez, Espèces nouvelles de mellifères de Barbarie, p. 11. Type material: Lectotype f, by designation of Tkalcu (1975b: 46), “Médénin” [Tunisia], MNHN (Paris).-Combination Osmia (Osmia) anceps Pérez in Friese (1911b: 89).-Synonymy with Osmia uncicornis Pérez in Tkalcu (1975b: 45), rejected by Haeseler (2005: 489).

1975 Osmia (Hemiosmia) pulchra Tkalcu, Acta Entomologica Bohemoslovaca (Praha), 72: 46. Type material: Holotype m, “Gafsa” [Tunisia], MNHN (Paris).-Synonymy in Haeseler (2005: 475).

Distribution- Europe:E. Northern Africa: LAR, TN; DZ, MA.

Identification-Keys, Descriptions: Haeseler (2005); Tkalcu (1975b).

Nesting biology: Unknown.

Flower preferences: Probably oligolectic on Fabaceae (A. Müller, unpublished, based on 4 pollen samples from 3 different localities and on field observations).

Osmia (Hemiosmia) argyropyga Pérez, 1879

1879 Osmia argyropyga Pérez, Actes de la Société Linnéenne de Bordeaux, 33: 175. Type material: Lectotype f, by designation of Tkalcu (1975b: 38), “Marseille” [France], MNHN (Paris). Type species of Hemiosmia Tkalcu.-Combination Osmia (Acanthosmia) argyropyga Pérez in Schmiedeknecht (1885: 21 [887]). Combination Osmia (Osmia) argyropyga Pérez in Friese (1911b: 90).

1879 Osmia entoprocta Pérez, Actes de la Société Linnéenne de Bordeaux, 33: 179. Type material: Lectotype m, by designation of Tkalcu (1975b: 38), “Marseille” [France], MNHN (Paris).-Combination Osmia (Helicosmia) entoprocta Pérez in Schmiedeknecht (1885: 22 [888]). Combination Osmia (Osmia) entoprocta Pérez in Friese (1911b: 89).-Synonymy in Tkalcu (1975b: 38).

Distribution-Europe: E, F, I, P. Northern Africa: DZ, MA, TN.

Identification-Keys, Descriptions: Benoist (1931); Ducke (1900); Haeseler (2005); Schmiedeknecht (1885-1886); Tkalcu (1975b).

Nesting biology-Nesting site: Abandoned cell of Megachile (Chalicodoma) pyrenaica. Nesting material: Several females were observed to collect leaf material on Helianthemum. (Grandi, 1962; A. Müller, personal observation)

Flower preferences: Probably oligolectic on Fabaceae (A. Müller, unpublished, based on field observations and 16 pollen samples from 12 different localities).

Osmia (Hemiosmia) balearica Schmiedeknecht, 1886

1886 Osmia balearica Schmiedeknecht, Apidae Europaeae, vol. 2, p. 177 [1043]. Type material: Lectotype m, by designation of Haeseler (2005: 477), “Palma” [Spain: Balearic Islands], ZMHB (Berlin).-Combination Osmia (Helicosmia) balearica Schmiedeknecht in Schmiedeknecht (1885: 22 [888]). Combination Osmia (Osmia) balearica Schmiedeknecht in Friese (1911b: 89).

Distribution-Europe: E, E(Ba). Northern Africa: ETLAR, MA, TN. Southwestern Asia: IL.

Identification-Keys, Descriptions:Ducke (1900);Haeseler (2005); Schmiedeknecht (1885-1886); Tkalcu (1975b).

Nesting biology-Nesting site: Excavated burrows (3-5cm deep) in loose sandy ground with one cell at the end or with several cells constructed closely side by side. The burrows are often near dead plants whose roots serve to attach the cells in the ground. Reports on nesting in empty snail shells are wrong. Nesting material: The cells are entirely made of chewed leaves (e.g. from Lotus, Medicago, Convolvulus, Cistus, Ononis). (Haeseler, 2005, 2008; G. Le Goff, personal observation)

Flower preferences: Probably oligolectic on Fabaceae; pollen sources: Lotus creticus (Haeseler, 2008).

Osmia (Hemiosmia) chrysolepta Haeseler, 2005

2005 Osmia (Hemiosmia) chrysolepta Haeseler, Entomofauna (Ansfelden), 26: 479. Type material: Holotype m, “Tel-Aviv” [Israel], Schwarz Collection (Ansfelden); paratypes mm, ff.

Distribution- Northern Africa: ET, LAR. Southwestern Asia: IL, JOR.

Identification-Keys, Descriptions: No supplementary or more detailed morphological description known.

Nesting biology: Unknown.

Flower preferences: Probably oligolectic on Fabaceae (A. Müller, unpublished, based on 5 pollen samples from 2 different localities).

Osmia (Hemiosmia) uncicornis Pérez, 1895

1895 Osmia uncicornis Pérez, Espèces nouvelles de mellifères de Barbarie, p. 10. Type material: m(m), no original material known.-Combination Osmia (Osmia) uncicornis Pérez in Friese (1911b: 89).

Distribution-Europe: E, P. Northern Africa: MA; DZ, TN.

Identification-Keys, Descriptions: Haeseler (2005); Tkalcu (1975b).

Nesting biology-Nesting site: Excavated burrows (3-5cm deep) in loose sandy ground with one cell at the end or with several cells constructed closely side by side. The burrows are often near dead plants whose roots serve to attach the cells in the ground. Reports on nesting in empty snail shells are wrong. Nesting material: The cells are entirely made of chewed leaves (e.g. from Lotus, Medicago, Convolvulus, Cistus). Cleptoparasite: possibly Stelis ortizi. (Haeseler, 2005, 2008; Baldock et al., 2018)

Flower preferences: Probably oligolectic on Fabaceae; pollen sources: Medicago marina, Lotus creticus (Haeseler, 2008; Baldock et al., 2018; A. Müller, unpublished, based on 18 pollen samples from 11 different localities).

difficilis species group (“Exosmia“)

Osmia (Hemiosmia) difficilis Morawitz, 1875

1875 Osmia difficilis Morawitz, Travel to Turkestan by A. P. Fedtschenko, p. 91. Type material: f(f), “in valle Sarafschan” [Tajikistan]. Type species of Exosmia Tkalcu.-Combination Osmia (Osmia) difficilis Morawitz in Friese (1911b: 87). Combination Osmia (Exosmia) difficilis Morawitz in Zanden (1988b: 125) and in Warncke (1988b: 397).

1875 Osmia falcata Morawitz, Travel to Turkestan by A. P. Fedtschenko, p. 102. Type material: m(m), “in valle Sarafschan” [Tajikistan].-Combination Osmia (Osmia) falcata Morawitz in Friese (1911b: 90).-Synonymy in Popov (1960a: 435).

1935 Osmia alborufa Alfken, Entomologische Rundschau (Stuttgart), 52: 161. Type material: Holotype f, “bei Ankara in Anatolien und auf der Reise nach da” [Turkey], SMFD (Frankfurt); paratype f.-Synonymy in Warncke (1988b: 398).

Distribution-Northern Asia: KS, KZ, RUS, TJ, UZ. Southwestern Asia: IL, IR, TR.

Identification-Keys, Descriptions: Ducke (1900); Popov (1960a: 435-437); Tkalcu (1979: 321); Warncke (1988b); Zanden (1987: 73-74).

Nesting biology-Nesting site: Excavated burrow (4cm deep) in very loose, sandy to gravelly ground with one cell at the end. Nesting material: The urn-shaped cell, which had a length of 15mm and a maximal width of 8mm was entirely made of chewed leaves. Although consisting only of leaf pulp, the cell walls (ranging in thickness from 0.3mm to 1mm) were surprisingly solid withstanding high physical pressure. In contrast to O. balearica and O. uncicornis, the cell was not attached to roots in the ground. (C. Sedivy, C. Praz and A. Müller, unpublished)

Flower preferences: Probably oligolectic on Fabaceae (A. Müller, unpublished, based on 15 pollen samples from 11 different localities and the pollen content of 1 brood cell, which exclusively contained pollen of Astragalus).

Osmia (Hemiosmia) iberica Zanden, 1987

1987 Osmia (Exosmia) iberica Zanden, Reichenbachia (Dresden), 25: 73. Type material: Holotype m, “La Gargenta (Caceres)” [Spain], RMNH (Leiden); paratypes mm, ff.

1988 Osmia (Exosmia) difficilis clanga Warncke, Entomofauna (Ansfelden), 9: 398. Type material: Holotypus m, “Alia de las Bojes/Granada, 1200 m” [Spain], OLML (Linz).-Synonymy in Zanden (1991c: 166).

Distribution-Europe: E, P.

Identification-Keys, Descriptions: No supplementary or more detailed morphological description known.

Nesting biology: Unknown.

Flower preferences: Possibly polylectic; pollen sources recorded so far are Fabaceae and Antirrhineae (A. Müller, unpublished, based on 3 pollen samples from 2 different localities). In Portugal, Dorycnium hirsutum (Fabaceae) is the only confirmed pollen source in Portugal (Baldock et al., 2018).