Hylaeus gibbus Saunders, 1850

Straka, Jakub & Bogusch, Petr, 2011, Contribution to the taxonomy of the Hylaeus gibbus species group in Europe (Hymenoptera, Apoidea and Colletidae), Zootaxa 2932, pp. 51-67 : 61-63

Hylaeus gibbus Saunders, 1850

(Tabs1–2; 2, 7, 8, 14, 16, 21, 22, 29, 30)

Hylaeus gibbus Saunders, 1850 : p. 59; designated based on two stylopised specimens ( Hylecthrus quercus Saunders, 1850 ); the lectotype was examined.

? = Prosopis mixta Schenck, 1861 : p. 313, 318; nec Prosopis mixta Smith, 1851 ; Schenck’s collection and most of the type material was destroyed; the type was not found in the museum in Frankfurt am Main where the remnant is deposited.

= Hylaeus aemulus Förster, 1871 : p. 991; the type was examined.

= Hylaeus foveolatus Förster, 1871 : p. 993; the type was examined; the lectotype was designated.

= Hylaeus kirschbaumi Förster, 1871 : p. 1081; nomen novum for Prosopis mixta Schenck, 1861 .

= Prosopis nigripes Pérez, 1903 : p. CCXXXIII; the lectotype was examined.

Type material examined. H. gibbus Saunders, 1850 : LECTOTYPE: Epiro, Sinus Ambracicus, Ƥ, labelled: “SYN- / TYPE (circular card, bordered by blue lines, printed label) // Hylectr. / quercus / 3. exuv. / Albuia (handwriting) // Hylaeus gibbus / S.S. Saunders / Ƥ Lectoholotypus / Blüthgen det. 1958. (handwriting, the last line printed, except the number 8) // Ex Saunders Fireign / Stylopidae . Oxford Uni. / Mus. of Nat. Hist. / ( OUMNH) (printed) // TYPE HYME 2761-1 / Hylaeus gibbus / Saunders, 1850 / HOPE ENT. COLL., OUMNH (printed)”. PARALECTOTYPE: Ƥ, with nearly identical labels as holotype, Blüthgen designed this specimen as “Lectoparatypoid”, type number 2761- 2. Lectotype and Paralectotype in OUMNH. H. aemulus Förster, 1871 : HOLOTYPE (by monotypy): Germany, 3, labelled: “ Type (bordered by black lines, printed label on pale purple-red card) // Hylaeus / aemulus Frst / A. Först- er det. (handwriting) // 1. (printed, on light yellow paper) // aemulus Frst. (bordered by blue lines, handwriting) // Prosopis 3 / genalis Ths / J.D Alfken det. (printed label, sex character and second line handwriting)”. Holotype in SNSB. H. foveolatus Förster, 1871 : LECTOTYPE (designed): Germany, Aachen, 3, labelled: “Cotype (bordered by black lines, printed label on pale purple-red card) // Hylaeus / foveolatus Frst / A. Förster det. (handwriting) // Aachen / 3. (handwriting) // 99. (handwriting) // Prosopis 3 / confusa Nyl / J.D Alfken det. (printed label, sex character and second line handwriting)”. Holotype in SNSB. Prosopis nigripes Pérez, 1903 : LECTOTYPE: France, 3, labelled: “Sta Fog la gi / 22 VII 10 (handwriting) // (card with glued metasoma) // MUSÉUM PARIS / R. Bouoise (first line printed, second handwriting) // nigripes / J.P. 3 (red handwriting) // MUSEUM PARIS / EY0000001553 (printed) // LECTOTYPE (printed on red card)”. Holotype in MNHN.

Additional material examined. Bulgaria: BURGAS: Sandanská bistrica river valley, Sandanski env., 400 m, 28. v.1999, 1 Ƥ, 2. vi.1999, 1 3, 28. vi.2000, 1 Ƥ, J. Straka lgt., JSPC; Sandanski env., 2. viii.2000, 1 Ƥ, P. Bogusch lgt., PBHC; Croatia: Makarska, Biokovo, 3.–17. vi.2003, 1 3, L. Vidlička lgt., PBHC; Czech Republic: MORA- VIA: Šobes, Podyjí National Park, 7. v.2007, 1 3, P. Bogusch lgt., PBHC; Tasovice env., stone quarry, 30. vii.2008, 1 3, yellow pan traps, J. Farkač, J. Straka & V. Vrabec lgt., JSPC; France: HAUTES ALPES: Gouffre, Briancon 18 km S, 900 m, 6. vi.1997, 1 3, St. Alban, Briancon 20 km S, 6. vi.1997, 1 Ƥ, Ch. Schmid-Egger lgt., CSEC; PROVENCE: Alpes Maritimes Mts.: Saorge, 680 m, 13. vii.2009, 3 3, 4 ƤƤ, Molliéres SW, 800–1400 m, 16. vii.2009, 1 3, 1 Ƥ, St. Sauveur-sur-Tinée 6 km N, 730 m, 16. vii.2009, 1 Ƥ, La Brigue, 800 m, 10. vii.2010, 2 3, Ch. Schmid- Egger lgt., CSEC; VAUCLUSE: Roussillon 2 km E; 9. vi.1997, 4 3, 1 Ƥ, Ch. Schmid-Egger lgt., CSEC; Germany: BADEN-WÜRTTEMBERG: Kaiserstuhl, Vogtsburg/Badberg, 16. viii.2008, 3 3, 5 ƤƤ, Ch. Schmid-Egger lgt., CSEC; Greece: Olympos, 2100 m, 4. vi.1937, 1 Ƥ, Bartoň lgt., NMPC; Italy: LOMBARDIA: Trevisio, Sondrio 6 km E, Valtellina, 500 m, 9. vii.2006, 1 3, Ch. Schmid-Egger lgt., CSEC; PIEMONTE: San Bernado, 2 km W, 1300 m, 10. vii.2009, 1 Ƥ, St. Lorenzo, S of Cuneo, 900 m, 10. vii.2009, 1 3, Stroppo, Valle Maira, 1280m, 17.vi.2009, Ch. Schmid-Egger lgt., CSEC; TRENTINO-ALTO ADIGE: Dro, Marocche 2 km N, Trento 16 km SW, 240 m, 13. v.2006, 4 3, Pietramurata, Trento 15 km SW, 13. v.2006, 1 3, Oris/Eyrs, Vinschgau, 8. vi.2007, 1 3, Ch. Schmid-Egger lgt., CSEC; VALLE D'AOSTA: west of Arwier, Aosta 12 km W, 700 m, 3. viii.1997, 1 3, 1 Ƥ, 25. vii.1999, 2 ƤƤ, Fossaz, Aosta 10 km W, 8. vii.1995, 1 Ƥ, Pondel, Aosta 8 km SW, 1000 m, 3. viii.1997, 1 3, St. Pierre, Aosta 6 km W, 750 m, 27. vi.1996, 1 3, 3. viii.1997, 2 3, Ch. Schmid-Egger lgt., CSEC; VENETO: Monte, Verona 20 km NW, 450 m,13. v.2006, 1 3, Ch. Schmid-Egger lgt., CSEC; Slovakia: Abrod Nat. Res., Velké Leváre env., 6. vii.2008, 1 Ƥ, 6. viii.2008, 1 Ƥ, J. Straka & P. Bogusch lgt., JSPC; Sekule, Moravský Ján env., 14. vi.2008, 2 ƤƤ, 5. viii.2008, 2 3, 3 ƤƤ, J. Straka & P. Bogusch lgt., JSPC; Šišulákovce, Lakšárska Nová Ves env., 14. vi.2008, 1 Ƥ, J. Straka lgt., JSPC; Switzerland: WALLIS: Leuk 2 km E, 29. viii.1999, 1 3, 1 Ƥ, Ch. Schmid-Egger lgt., CSEC, Leuk, 1200 m, vi.–viii. 2006, 3 3, 13 ƤƤ, Y.Chittaro lgt., JSPC, all P. Bogusch & J. Straka det.

Redescription of male. Body length: 5.5–6.5 mm.

Coloration. Large part of mandibles, labrum in some specimens (especially second generation), lower part of scapus, clypeus, supraclypeal area and lower part of paraocular area, inner and dorsal part of foretibia, base of mesotibia, distal half of metatibia, mid- and hind-metatarsi except apex, pronotum dorsally, pronotal lobe and spot on tegula yellow. Lower part of flagellum reddish. Other body parts all black.

Head. Width: 1.40–1.70 mm; length: 1.40–1.70 mm; width/length: 1.01–1.07. Clypeus, supraclypeal area, and lower half of paraocular area sparsely punctated, punctures ill-defined, in most specimens distinct, one to four diameters apart, interspaces microsculptured, slightly shiny to dull. Frons above antennae with small free unpunctated space, about as long as diameter of antennal socket; rest of frons and vertex distinctly and densely punctated, punctures well-developed, interspaces small, less than half diameter apart in all parts (fig. 7). Malar area short, microridged. Gena punctated and weakly microridged, punctures ill-defined, distinct. Preoccipital ridge developed, with distinct, but weak ledge in 1st generation and with well-developed and distinct ledge in 2nd generation (cf. fig. 14). Antennae very variable, antennomere V nearly as short as III and IV. shorter than wide in 1st generation, or antennomeres III and IV subequal, quadratic, V about 1.5x longer than wide in 2nd generation.

Mesosoma. Scutum densely and uniformly punctated, punctures well-developed, about half to less than half diameter apart, interspaces microsculptured, slightly shiny to dull. Mesopleuron less densely punctated than scutum and punctures larger than on scutum; in central part, punctures well-defined, one to less than one diameter apart, interspaces microsculptured, shiny; on hypoepimeral area, punctures ill-defined, about half to two diameters apart, interspaces shiny (fig. 16). Central part of propodeum rugose, with ill-defined lamella separating anterior (roughly sculptured) and posterior (smoothly sculptured) parts. Legs not modified, densely micropunctated, punctures ill-defined.

Metasoma. Terga distinctly hairy, first tergum with distinct apicolateral bands. Tergum I sparsely, but distinctly punctated, punctures ill-defined, about half to three diameters apart, interspaces finely microsculptured, shiny (fig. 21). Other terga more distinctly, densely and roughly sculptured. Sternum III in most specimens without any distinct elevation in central part, rarely with two small separate circular elevations. Sterna II to V uniformly sparsely punctated, punctures large, ill-defined, half to three diameters apart, interspaces shiny. Sternum VII with apical lobes L-shaped, apex acute (fig. 29). Sternum VIII with distinct medial process, process narrow, about twice as long as wide (fig. 30).

Redescription of female (Lectotype). Body length: 6.0 mm.

Coloration. Apical and medial part of clypeus, all lower paraocular area between clypeus and eye margin (cf. fig. 2), inner part of foretibia, base of mesotibia, distal half of metatibia, mid- and hind-metatarsi except apex, pronotal lobe, pronotum dorsally and part of tegula yellow. Lower part of flagellum reddish. Other body parts all black.

Head. Width: 1.93 mm; length: 1.78 mm. Clypeus, supraclypeal area and lower half of paraocular area sparsely punctated, punctures shallow, but well-defined, less than one to four diameters apart, interspaces strongly microsculptured, dull. Frons above antennae with small free unpunctated space, not longer than diameter of antennal socket; rest of frons and vertex densely punctated, punctures well-developed, but evanescent in microridges, interspaces small, about half to less than half diameter apart (cf. fig. 8). Malar area short, microridged (cf. fig. 2). Gena punctated and densely ridged, punctures evanescent in fine ridges. Preoccipital ridge developed, with welldeveloped and distinct ledge (cf. fig. 14). Antennae short, antennomere III about as long as wide, V. and especially IV. even shorter, transverse.

Mesosoma. Scutum densely and uniformly punctated, punctures well-developed, half to less than half diameter apart, interspaces microsculptured, dull. Mesopleuron densely punctated, sculpture similar to that on scutum, punctures uniform in size and distribution like on scutum; in central part, most punctures about half to less than half diameter apart, interspaces microsculptured, slightly shiny; on hypoepimeral area, punctures ill-defined, half to three diameters apart, interspaces microridged, slightly shiny to dull (cf. fig. 16). Central part of propodeum rugose; dorsal part roughly sculptured and posterior part smoothly sculptured. Legs not modified, densely micropunctated, punctures ill-defined.

Metasoma. Terga distinctly hairy, first tergum with distinct apicolateral bands. Tergum I finely and sparsely punctated, punctures ill-defined, nearly indistinct, about one to four diameters apart, interspaces distinctly microsculptured, slightly shiny (cf. fig. 22). Other terga more distinctly and densely sculptured. Sterna II to V uniformly punctated, punctures large, ill-defined, one to three diameters apart, interspaces shiny.

Variability of females. Body length: 6.0–6.5 mm. Head width: 1.70–1.95 mm; head length: 1.70–1.85 mm; width/length: 1.00–1.08. Types possess abnormal colloration. Tipical coloration: Only base of all tibiae, pronotal lobe, pronotum dorsally, tegula partly and lower part of paraocular area between eye and clypeus yellow. Most of these pale markings could be slightly reduced in specimens of the first generation. Apical part of clypeus red in some specimens. Lower part of flagellum reddish. Other body parts all black.

Distribution and ecology. Hylaeus gibbus is a thermophilous, Mediterranean species that is distributed widely in southern Europe. This species is collected mostly on bushy, grassy, steppe or ruderal biotopes. This species reaches northwards to southern Germany (Baden-Württembergs) and the northern Panonian lowland (south Slovakia and south Moravia in the Czech Republic). Koster (1986) and Westrich (1990) combined data on H. gibbus and H. incongruus in their distribution information. We present a distribution range specifically for H. gibbus .

Comments. 1) The lectotype and paralectotype are stylopised specimens with one empty male puparium each. Stylopised specimens of the genus Hylaeus are usually abnormally developed, especially in their sexual characteristics. The type material of Hylaeus gibbus are abnormally yellow (see the description of the lectotype), but they are normal females based on morphological characteristics and are easily recognisable as the species. 2) This species is extremely variable. Specifically, the differences between the first and second generations are unusual in males. The conspecifity of studied specimens is determined by collecting specimens from the same sites during the season. When making the determination, attention must be paid to which characteristics are being using for spring and summer specimens (see Differential diagnosis of males).