Hoplitis (Hoplitis) onosmaevae Aubert, 2024

Aubert, Matthieu, Mueller, Andreas & Praz, Christophe, 2024, A new osmiine bee with a spectacular geographic disjunction: Hoplitis (Hoplitis) onosmaevae sp. nov. (Hymenoptera, Anthophila, Megachilidae), Alpine Entomology 8, pp. 65-79 : 65

Hoplitis (Hoplitis) onosmaevae Aubert sp. nov.

Figs 3-9 , 10-14 , 16-19 , 20-21 , 24

Type material.

Holotype. France • ♀; Alpes-Maritimes, Tinée Valley, Saint-Etienne-de-Tinée, across from Bousiéyas, southern slopes of L’Alpe Mountain (type locality part of Mercantour National Park); 44.315°N, 6.859°E; 1985 m; 13.7.2018; Matthieu Aubert leg.; Onosma stand; MNHN (inventory number: EY35781).

Paratypes. France (2♀, 3♂) • 1♀, 1♂; same data as for holotype; ETHZ (♀) and MNHN (♂) coll. (MNHN inventory number: EY35831) • 1♂; Alpes-Maritimes, Tinée Valley, Saint-Etienne-de-Tinée, across from Bousiéyas, southern slopes of L’Alpe Mountain; 44.319°N, 6.858°E; 1920 m; 13.7.2018; Matthieu Aubert leg.; Onosma stand; ETHZ. • 1♀, 1♂; Alpes-Maritimes, Tinée Valley, Saint-Dalmas-le-Selvage, vallon du torrent de Jalorgues, Bouden/Bouding; 44.272°N, 6.843°E; 1705 m; 23.6.2020; Matthieu Aubert leg.; MAC. Iraq (1♂) • 1♂; Dahuk governorate, Mt. Gara; 37.015833°N, 43.350556°E; 1912 m, 11.5.2023, D. Baiocchi leg.; D. Baiocchi coll. Turkey (4♀, 6♂) • 1♂; Bolu province, Bolu lake env.; 21.6.1993; M. Halada leg.; ETHZ. • 2♂; Antalya province, 4 km east of Saklikent; 36°52.51'N, 30°30.954'E; approx. 1600 m; 30.5.2009; John S. Ascher, Jerome G. Rozen, Hikmet Özbek leg.; ETHZ. • 1♀; Mersin province, Mersin district, between Gülnar and Ermenek; 36°21.380'N, 33°18.841'E; 1075 m; 24.5.2006; Erwin Scheuchl leg.; ETHZ. • 1♀; Mersin province, Mut district, Sertavul Pass; 36.812°N, 33.32°E; 1300 m; 7.6.1968; Josef Gusenleitner leg.; ETHZ. • 1♀; Mersin province, Mut district, Kirobasi; approx. 36.723°N, 33.900°E; 1450 m; 19.6.1997; Marek Halada leg.; ETHZ. • 1♀; Mersin province, Mut district, 40 km east of Cornelek; approx. 36.630°N, 33.866°E; 1700 m; 29.5.1996; Mi. Halada leg.; ETHZ. • 1♂; Mersin province, Toroslar district, Yeniköy; 37.08°N, 34.41°E; 1200 m; 29.5.1993; Stephan Risch leg.; ETHZ. • 2♂; Bitlis province, Mount Nemrut, 36.626°N, 42.186°E; 2350 m; 25.5.1989; Klaus Warncke leg.; ETHZ.

See Suppl. material 1 for a complete list of records as well as Fig. 2 for a distribution map.

Diagnosis.

In most species of Hoplitis (Hoplitis) , the length of the proboscis is at most one-third as long as the body. Only H. linguaria , H. holmboei , H. homalocera and H. semilinguaria have a longer proboscis, which reaches about half of the body length. Hoplitis onosmaevae possesses an even longer proboscis, which is approximately as long as the body (Fig. 3 ). In both sexes of H. holmboei and H. homalocera , the vertex is comparatively short (ocelloccipital distance less than two ocellar diameters) and, when seen in front view, not elevated behind ocelli, but regularly rounded across its width; in H. onosmaevae the vertex is longer (ocelloccipital distance about three ocellar diameters) and is strongly elevated behind ocelli (Figs 3 , 4 ). Hoplitis onosmaevae differs from H. linguaria in both sexes by the color of the tegulae, which are reddish-orange in H. linguaria and brown (although often reddish brown along the external margin) in H. onosmaevae . In the female, H. onosmaevae can be distinguished from H. linguaria by the lateral margins of S6, which have a thickened rim, and by the apical margin of S6, which ends medially in a sharp spine as in H. adunca (Fig. 7 ); in H. linguaria , S6 lacks thickened rims or a medioapical spine. Moreover, the punctation of the supraclypeal area in H. onosmaevae is comparatively fine and dense with only small interspaces especially in the middle, whereas it is sparse in H. linguaria in the middle. In the male, H. onosmaevae can be distinguished from H. linguaria by the shape of the membranous appendage at the apical margin of S6 and the form of the gonostylus. In H. onosmaevae , the appendage of S6 is longitudinally raised medially, wider at the base than at the apex, tapers into a narrowed tip and is covered with short light orange hairs in the middle (Figs 12 , 14 ). The gonostylus is threadlike and slightly clubbed at the apex. In H. linguaria , the membraneous appendage of S6 is flat, short and distinctly bilobed and the gonostylus is much thicker and narrowed at the apex. Compared to H. semilinguaria , which is known only in the female, the inner margins of the compound eyes are diverging towards the clypeus in H. onosmaevae , whereas they are parallel in H. semilinguaria . In addition, S6 of H. linguaria lacks thickened marginal rims as is probably also the case in H. semilinguaria . Tkalců (1992) compared these two species and did not provide any information on the structure of S6.

Hoplitis onosmaevae can be separated from the common species H. adunca , which is similar in size and also has thickened marginal rims and a medioapical spine on female S6, by the yellowish-brown hind tibial spurs (Fig. 9 ) (tibial spur black in H. adunca ), in addition to the longer proboscis.

Description.

Female (habitus: Figs 3 , 18 - 20 , 24 ). Body length 9-10 mm.

Integument color. Cuticula generally black, except where indicated hereafter. Proboscis brown, glossa orange. Cuticula reddish-brown laterally along apical margin of clypeus and more or less along margin of sternites and tergites, on internal surface of femora, apical part of leg segments, especially last tarsi and claws. All tibial spurs yellowish-brown to orange. Tegulae dark brown, external margin often reddish brown. Wing venation dark brown. Eyes grey-brown in the field. Vestiture color. Generally white, including scopa, except where indicated hereafter. Hairs slightly darker, greyish brown, on scutum. Some hairs along apical margin of clypeus and on tergal discs yellowish white. Hairs on internal surface of tibiae and tarsi, on basal part of femora and apical half of trochanters yellowish-orange.

Head. Vertex strongly elevated and tilted forward when seen in front or 3/4 view. Ocelloccipital distance approximately equal to three ocellar diameters (Fig. 4 ). Inner margin of compound eyes slightly diverging below (ratio between upper and lower interocular distance approximately 0,92). Clypeus strongly convex, protruding, apical margin with approximately nine teeth, lateral teeth triangular, median teeth nearly cylindrical (Figs 4 , 5 ). Mandibles tridentate, apical tooth elongate, acute (Fig. 5 ). Proboscis equal to body length when fully extended, galea half as long as body, with short bristles basally. Labrum longer that wide. Head overall shiny, shagreened only on parts of clypeus (see below), densely punctate; interspaces absent or narrow, except on vertex and genae where interspaces can be as wide as one puncture diameter, on frons laterally and close to ocellar area where the interspaces can reach two puncture diameters. Frons along frontal line and supraclypeal area more densely and finely punctate (supraclypeal area sometimes comprises some narrow interspaces centrally). Clypeus more strongly punctate than elsewhere on head, interspaces up to 1 or 2 puncture diameters, punctation becoming denser and finer apically; clypeus in basal half with median impunctate longitudinal line (Fig. 5 ), line sometimes reaching apical margin. Labrum unpunctured and shiny in basal third, mat and shagreened apically, here more or less punctate. Proboscis surface unpunctured, smooth and shiny on the front, mat and shagreened laterally and dorsally. Antennae. FL2 slightly longer than FL3 and FL4 together; FL (5-6-)7-10 brown-orange below (Fig. 5 ).

Mesosoma. Pronotum weakly shagreened with shallow punctation, but shiny. Mesepisternum (except ventral part), scutum and scutellum shiny, densely and relatively strongly punctate, interspaces well visible, up to 2 to 3 punctures diameters on central part of scutum. Mesepisternal concavity shiny with sparse punctation. Axillae shagreened, densely and finely punctate. Metanotum shiny with distinct punctation. Metepisternum weakly shagreened but shiny. Propodeal triangle nearly entirely shagreened, shiny in its lower part; propodeal posteriorly nearly impunctate around propodeal pit, more densely punctate laterally; sides of propodeum densely and finely punctate (Fig. 8 ). Mesepisternum ventrally impressed along longitudinal axis, this concavity open posteriorly between mid-legs insertions, here shiny and sparsely punctate. Mesosoma entirely hairy except on propodeal triangle and propodeal pit (Fig. 8 ). Hairs on scutellum, lateral part of mesepisternum and on propodeum as long as on vertex, shorter on scutum and even more so on ventral parts of mesepisternum. Legs. External extensions on apex of first and mid tibiae relatively thin, elongated and curved. Spur of front tibiae modified, internal margin lamellar, external margin thick and curved, apex of spur pointed, internally with a minute fringe of hairs. Front metatarsi basally with an internal notch. Inner spurs of hind tibiae straight and regularly tapering, only slightly curved apically (Fig. 9 ).

Metasoma. T1 smooth and shiny, unpunctured on vertical part, disk with regular, sparse punctation (interspaces up to 4 puncture diameters), punctation denser and finer toward the margin. T2-3 similar to T1, but impressed basally, punctation sparser on T2 than on T1, becoming even sparser on T3. T4 similar to T3, slightly more shagreened, punctation rugose. T5-6 shagreened, punctation denser and more rugose than on T4. All terga with a thin impunctate margin, impunctate margin larger on T6. In fresh specimens, T1-4 laterally with long erect white hairs, hairs on T1 as long as those on scutellum; T1-4 with white, interrupted apical fasciae, T5 with continuous apical fasciae, T6 with decumbent, light hairs. S1-6 shiny but slightly shagreened with moderately dense (2 to 3 puncture diameters), rugose punctation, their margin impunctate. S6 laterally with a thickened rim, rim interrupted before apex; apex pointed (Fig. 7 ).

Male (habitus: Figs 16 , 17 ). Body length 10-12 mm.

Integument color. As in ♀ except when mentioned below. Eyes grey-green in the field. Vestiture color. Predominantly brown-orange in fresh specimens, fading to yellowish to greyish white.

Head. Vertex as in ♀. Inner orbital edges slightly diverging below (less so than in ♀). Clypeus protruding, apical margin denticulate, but less regularly and strongly than in ♀; teeth partly hidden by dense apical fringe of hairs. Mandibles bidentate, upper tooth short, apical tooth sharp. Proboscis, galea and labrum proportions as in ♀. Vestiture very dense on frons, paraocular and supraclypeal areas and clypeus. Punctation overall more homogeneous than in ♀, finer and denser on average; clypeus entirely punctate except a narrow impunctate area along lateral margins, punctation fine and dense, difficult to see due to dense vestiture. Labrum medially shiny, unpunctured or with sparse punctation, shagreened and more densely punctate laterally. Antennae. Scape densely punctate and hairy, 3 times as long as wide at apex; width at apex twice basal width. FL2 triangular, at most 1,5 as long as wide at apex, as long as FL3 and FL4 together. FL3 and FL4 twice as wide as long. FL8-10 nearly square, FL11 approximately 1,5 times as long as wide. Flagella flattened dorso-ventrally; only internal surface of FL2 (distinctly) and FL3 (slightly) convex. FL5- or FL6-11 orange ventrally (Figs 10 , 11 ).

Mesosoma and legs. As in ♀ except where indicated hereafter. Punctation denser and finer on scutum and lateral parts of mesepisternum, and denser on area around propodeal pit.

Metasoma. Tergal punctation generally as in ♀ but punctures less impressed and area with fine punctation on tergal margins wider. T7 finely punctate and shagreened basally, smooth and shiny medially, punctation becoming rugose and sparse apically. T2-3 depressed basally. T6 with a strong tooth laterally, apical margin irregular, slightly sinuate medially. In dorsal view, lateral margin of T7 slightly concave medially, apical margin rounded (Fig. 13 ). Metasomal vestiture as in ♀ except where indicated hereafter. Lateral fasciae of T1 less pronounced and more elongated, T2-5 with shorter hairs, T6 with continuous fasciae on apical margin, fasciae narrower in the middle but not interrupted, T7 with long hairs laterally but fewer hairs medially. S1 thicker than S2-4, with lamellar margin. S2-5 with a transverse premarginal gibbosity (inconspicuous on S5), S5 with longitudinal central groove. Margins of S1-4 slightly sinuate, S5 straight medially, rounded laterally. S6 basally with short and wide translucent lamella, median extension trapezoidal, with sinuate margins (Figs 12 , 14 ; see also Diagnosis). S1 with strong and dense punctation on thickened part. S2-4 with dense punctation, shagreened and with fine punctation basally and premarginally, transverse gibbosities smooth and shiny, with sparse punctation medially. Median extension of S6 mostly shagreened (Fig. 14 ). Apical margin of S1-3 with sparse fringe of relatively long hairs, apical fringe shorter on S4, almost absent on S5. S6 baso-laterally with dense and long fringe of hairs, hairs emerging behind translucent lamella; surface of median extension of S6 with short yellowish-orange hairs. Gonostyli thread-like, slightly clubbed apically.

Etymology.

The species epithet Hoplitis onosmaevae refers to the assumed close association with plants of the genus Onosma (see section on pollen hosts below) and to Maëva Gardenat, to whom the first author wishes to dedicate this species.

Distribution.

Known so far from the Mount Gara in northern Iraq (Dahuk Governorate), from the Nemrut Dağ in Eastern Turkey (Bitlis province), from the western and central Taurus Mountains in southern Turkey (Antalya and Mersin province), from the western Pontic Mountains in northwestern Turkey (Bolu Province) and from the Tinée Valley in the French southern Alps ( Provence-Alpes-Côte-d’Azur region) (Fig. 2 ). In France, the species appears to be extremely rare and localized. So far it has only been found at two sites separated by less than 5 km; at each site, only few individuals were observed (the estimated number of individuals was 3 and 10-20, respectively). The search for the species was unsuccessful in several other localities in the French southern Alps with populations of Onosma tricerosperma subsp. fastigiata . These localities were situated 10 km to 18 km to the east, the north and the southwest of the two known sites of H. onosmaevae . Localities surveyed were the Bachelard valley above Fours-Saint-Laurent (Alpes-de-Haute-Provence, Uvernet-Fours, 44.32°N, 6.69°E) between 1750 m and 1900 m on 11.7.2019 and 27.6.2020, the Ubaye upper-valley, around la Barge and Maljasset (Alpes-de-Hautes-Provence, Saint-Paul-sur-Ubaye, 44.59°N, 6.83°E) between 1700 m and 2150 m on 11.7.2019 and 25.6.2020, the Ubayette valley, around Larche (Alpes-de-Haute-Provence, Larche, 44.45°N, 6.45°E) between 1650 m and 2000 m on 13.7.2019, above Saint-Ours (Alpes-de-Haute-Provence, Val d’Oronaye, 44.48°N, 6.81°E) between 1800 m and 1950 m on 26.6.2020, and the Barlatte upper-valley (Alpes-Maritimes, Châteauneuf-d’Entraunes, 44.18°N, 6.83°E) between 1700 m and 1850 m (MNP core area) on 25.6.2022. However, some of these unsuccessful visits were not performed under ideal conditions (e.g. end of blooming time or low abundance of blooming host plants), so that the occurrence of H. onosmaevae at all these sites cannot be excluded with certainty.

Field observations.

Field observations were conducted at the "Vallon du torrent de Jalorgues" (Figs 15 , 22 ) on 23.6.2020, when Hoplitis onosmaevae was found for the first time, and on 28.6.2020. The first visit took place in good weather conditions and lasted from 10:00 to 15:30. Several females and males were seen, most observations and pictures were realized on that day and a nesting site was found. During the second visit, fewer individuals were observed, possibly due to the less favorable weather conditions and we focused on a closed nest found five days before, around which a single female was seen.

Behaviour at Onosma stands.

Several females were observed collecting pollen and nectar on flowers of Onosma tricerosperma subsp. fastigiata (Figs 18 , 20 , 21 ). After landing on the corolla, they entered the flower headfirst, clung to the style and then vibrated the flower by buzzing to extract the pollen. This behavior was observed several times. Each visited flower was sonicated usually twice during a few seconds. The females then collected nectar on the same flower and repeated the same sequence on the next flower. The bees landed frequently on the ground or on a stone between two flower visits to concentrate the nectar by widely spreading the mandibles and the labrum and slightly unfolding the proboscis (Fig. 19 ). Males were observed patrolling Onosma patches in their search for females, resting frequently nearby on the ground or on a stone (Figs 16 , 17 ). They sometimes interrupted their patrolling flights to ingest nectar from Onosma flowers.

Pollen hosts.

The pollen contained in the female scopae and the brood cells was morphologically identical to reference pollen samples of Onosma ; while the French samples certainly belong to Onosma , the unambiguous identification of Onosma pollen was not possible for the Turkish samples, as several closely related Boraginaceae genera with similar pollen morphology occur in Turkey.

Nesting biology.

A nesting site was found on 23.6.2020 in the "Vallon du torrent de Jalorgues" by observing the flight direction of a female leaving the main patch of host plants. The nesting site was situated at a distance of approximately 35-40 m from the Onosma patch, where three dead trunks of larch ( Larix decidua Miller, 1768) were present, one lying and two still standing (Fig. 22 ). Two nests in preexisting insect burrows were discovered, one in the lying trunk and the other in a standing trunk. One nest was left untouched, while the second was partially opened five days later. This nest consisted of an unknown number of brood cells, of which the two outermost were excavated. These cells were in line and parallel to the external surface of the tree trunk. The following nest architecture was observed (Fig. 25 ): 1. a nest plug composed of small pebbles glued together with fine sand, which was probably mixed with secretions (Fig. 23 ); 2. an empty chamber; 3. a partition constructed with sand, but without pebbles; 4. the outermost cell containing a solid provision mass (egg or larva not visible); 5. a partition built with sand; 6. the penultimate cell containing a solid provision mass (egg or larva not visible); 7. another partition built with sand.

Figures

Figure 2. Distribution map of Hoplitis onosmaevae sp. nov.

Figures 3 - 9. Hoplitis onosmaevae sp. nov., female (holotype). 3. Lateral view; 4. Head; 5. Clypeus and mandibles; 6. Metasoma, dorsal view; 7. Last sternum, ventral view; 8. Propodeum; 9. Inner spur of hind tibia, posterior view.

Figures 10 - 14. Hoplitis onosmaevae sp. nov., male. 10. Left antenna, dorsal view; 11. Left antenna, front view; 12. Sterna 3 - 6 (the metasoma was slightly extended to expose S 6); 13. Terga 5 - 7, dorsal view; 14. Membraneous appendage of sternum 6, lateral view.

Figures 15 - 19. Hoplitis onosmaevae sp. nov., foraging habitat and behaviour (France, Saint-Dalmas-le-Selvage, 23.6.2020). 15. Foraging habitat with patch of the host plant, Onosma tricerosperma subsp. fastigiata; 16. Male resting on stone between two patrolling flights, with unfolded proboscis; 17. Male resting on stone between two patrolling flights; 18. Female on a flower of Onosma tricerosperma subsp. fastigiata; 19. Female concentrating nectar with widely open mandibles.

Figures 20 - 25. Hoplitis onosmaevae sp. nov., nesting habitat and behaviour (France, Saint-Dalmas-le-Selvage, 23.6.2020, for photographs). 20. Female in buzzing position on a flower of Onosma tricerosperma subsp. fastigiata; 21. Female leaving a flower of Onosma tricerosperma subsp. fastigiata; 22. Nesting habitat with dead trunks of larch; 23. Nest entrance plugged with sand and pebbles; 24. Female near the nest entrance, which is visible at the bottom left; 25. Cross-section of nest (P = pollen provisions).