Merodon latens Vujić, Radenković & Likov sp. nov.

Figs 1 D, E, 2 B, 3 B, 4 B, 5 B, 6 A, B, 7 C, 8 C, 12 A, B, 13, 14 B, 15, 17

Type material examined.

Holotype: Spain • 1 ♂; Sierra Nevada, second valley; 37.102778, - 3.455277; 17 Jun. 2014; leg. A. Vujić, S. Radenković, S. Pérez- Bañón; in FSUNS . Paratypes. Spain • 7 ♂♂, 3 ♀♀; Andalusia, Almijara, Corbijo los Capotes; 36.879, - 3.7317; 11 Jun. 2003; leg. D. Doczkal; in DD collection . Spain, Andalusia, Granada, 37.25, - 3.25, 29–31 May 1925, leg. Zerny, 1 male in NHMW • 1 ♀; Andalusia, Granada; 1 Jun. 1925; leg. Zerny; in NHMW • 1 ♂, 1 ♀; Andalusia, Puerto de Santa Maria; 36.6401, - 6.2596; Apr. 1933; leg. S. Hering; in ZHMB • 1 ♀; Andalusia, Sierra de Baza; 37.422222, - 2.851944; 9 Jun. 2003; leg. D. Doczkal; in DD collection • 2 ♂♂; Andalusia, Sierra de Segura, Casas de Carrasco; 38.156666, - 2.678333; 7 Jun. 2003; leg. D. Doczkal; in DD collection • 1 ♂; Barcelona; 41.414247, 2.127128; May 1918; leg. H. Teunissen; in RMNH • 1 ♂; Burgos, Espinosa de Cervera; 12 Jun. 1992, 41.897516, - 3.467732; leg. M. Hull; in WML • 1 ♂; Castilla la Mancha, Sierra de Alcaraz, Riopar; 38.504722, - 2.46; 14 Jun. 2003; leg. D. Doczkal, in DD collection • 3 ♂♂, 2 ♀♀; Ciudad Real, Sierra de Santa Maria, Viso del Marques; 38.966666, - 3.9166666; 20 Apr. 1999; leg. M. E. Irwin; in HM collection • 1 ♂; Cortes de la Frontera, way to Grazalema, 36.593904, - 5.312444, 6 May 2015; leg. A. Vujić; in FSUNS • 1 ♂, 1 ♀; Cortijo los Capotes, Almijara; 36.878889; - 3.731667; 11 Jun 2003; leg. A. Ssymank; in SIZK • 1 ♂; Granada, Rio Lanjaron, near Lanjaron; 36.9437, - 3.469431; 28. Apr. 1966; leg. Lyneb. Martin, Langemark; in ZMUC • 3 ♂♂, 2 ♀♀; Granada, Sierra Nevada, near Padul; 37.0833333, - 3.1666667; 4 May 1966; leg. Martin; Langemark; in ZMUC • 1 ♂; Grazalema 2, Puerto Alamillo; 36.722683, - 5.333724; 8 May 2015; leg. A. Vujić; in FSUNS • 1 ♂; Leon, Mirantes de Luna; 42.841438, - 5.861399; 3 Jun. 1987; leg. M. A. Marcos-García; in FSUNS • 1 ♂; Lugros, Sierra Nevada; 37.183056, - 3.257778; 18 Jun. 2014, leg. A. Vujić, S. Radenković, S. Pérez-Bañón; in FSUNS • 1 ♂; Malaga, Alhaurin el Grande; 36.633333, - 4.683333; 1 May 1979; leg. H. Teunissen; in RMNH • 1 ♂; Malaga, Ronda; 16 Apr. 1955; leg. I. H. H. Yarow; in NHMUK • 1 ♂; Prov. Salamanca, Villar de Ciervo; 40.741661, - 6.741098; 24 May 1987; leg. Tschorsnig; in ZFMK • 1 ♂, 1 ♀; Sierra Nevada, first valley; 37.127777, - 3.445555; 17 Jun. 2014; leg. A. Vujić, S. Radenković, S. Pérez-Bañón; in FSUNS • 1 ♂; Sierra Nevada, Rio Lanjaron 2; 38.125555, - 3.870833; 28 Apr. 2019; leg. A. Vujić, S. Radenković; in FSUNS • 1 ♂, 1 ♀; Sierra Nevada N. P., road to San Jeronimo; 37.240277, - 3.48; 17 Jun. 2014, leg. X. Mengual; in ZFMK • 1 ♂; SW Spain, 4 km SE of Antequera; 37.002352, - 4.517977; 7 May 1981; leg. A. E. Stubbs; in NHMUK • 1 ♂; Puertollano; 38.697473, - 4.090701; in MNHN .

Diagnosis.

Similar to Merodon clavipes from which differs by the less broad metafemur of the male (from lateral view ~ 4 × longer than wide; Fig. 4 B) (<3 × longer than wide in M. clavipes; Fig. 4 A), less curved metafemur basally (strongly curved in M. clavipes; Fig. 4 A), and ventral pilosity on metafemur <2 × longer than dorsolateral (Fig. 4 B) (while> 2 × longer in M. clavipes; Fig. 4 A). Male genitalia are very similar to M. clavipes (Fig. 8 A), with the single difference in the shape of surstylus, especially of the posterior surstylar lobe: more arcuate ventrally in M. latens sp. nov. (Fig. 8 C: pl), and more or less straight in M. clavipes (Fig. 8 A: pl). Female of M. latens sp. nov. has less dense ventral pilosity on metafemur, with ventral pile as long as a dorsolateral pile (Fig. 14 B), while female of M. clavipes has denser and longer ventral pilosity on metafemur (Fig. 13 A). Molecular and morphometric data clearly separated these two species (Figs 15, 16, 17 and Suppl. material 3). Merodon latens sp. nov. is an Iberian endemic.

Description.

Male. Head. Basoflagellomere dark brown (Fig. 2 B), elongated, ~ 2 × longer than wide, and ~ 2.3 × longer than pedicel, convex dorsally; fossette dorsolateral; arista brown and thickened at basal third; arista ~ 1.3 × longer than basoflagellomere (Fig. 2 B); face and frons black, with whitish grey pollinosity; face covered with dense whitish pilosity; pile on frons dense, grey-yellow; oral margin small, black, sparsely pollinose; lunula shining black to brown, bare; eye contiguity ~ 13–15 facets long; vertical triangle isosceles, black, shiny, except grey pollinose anterior corner, covered with both black and yellow pile; ocellar triangle equilateral; occiput with grey-yellow, dense pollinosity; eyes densely covered with whitish grey pile (Fig. 12 A).

Thorax. Scutum and scutellum black with bronze lustre, covered with short, greyish yellow pile in anterior half; pilosity between wing bases entirely or mostly black; scutum with indistinct pollinose vittae; transverse suture with two medial pollinose maculae; posterior margin of scutum and all scutellum with long whitish pilosity (Fig. 3 B); posterodorsal part of anterior anepisternum, posterior anepisternum (except anteroventral angle), anterior anepimeron, dorsomedial anepimeron, and posterodorsal and anteroventral parts of katepisternum with long, dense, whitish pile; wings mostly covered with microtrichia; wing veins brown to black; calypteres whitish yellow; halteres yellow to brown; legs black; metafemur moderately broad, from lateral view ~ 4 × longer than wide, covered with long, whitish, yellow, and black pile (Fig. 4 B).

Abdomen. Elongated (Fig. 5 B), as long as mesonotum; terga black; terga 3 and 4 with distinct silver-grey pollinose fasciate maculae interrupted medially; pile on terga 1 and 2 whitish, while on terga 3–5 grey-yellow to reddish; sterna black, covered with whitish yellow pile; posterior margin of sternum 4 with characteristic circular posteromedial incision (Fig. 7 C).

Male genitalia (Fig. 8 C). Anterior surstylar lobe large, elongated and sickle-like (Fig. 8 C: al); posterior surstylar lobe rectangular, arcuate ventrally (Fig. 8 C: pl).

Female (Fig. 6 A, B). Similar to the male except for typical sexual dimorphism and the following characteristics: frons with broad pollinose vittae along eyes, occupying ~ 1 / 3 of the width of the frons from frontal view (Fig. 12 B); scutum between wing bases without black pilosity, only wing basis with few black pile in some specimens (Fig. 6 B); metafemur narrower (~ 3.5 × longer than wide), with ventral pilosity shorter than in male (Fig. 14 B); lateral sides of tergum 2 with reddish yellow maculae (Fig. 6 A); terga 3–5 with short adpressed black pilosity medially.

Distribution and biology.

The species range is limited to the Iberian Peninsula (Spain) (Fig. 13). It preferentially occurs in open sparsely-vegetated semi-arid environments, typically unimproved stony pasturage and open grassy areas within thermophilous Quercus forest. Adult males and females both showed territorial behaviour, flying close to the soil and through the vegetation. Flowers visited by adults are mostly umbellifers and Euphorbia . Flight period: April / June. Developmental stages: undescribed.

Etymology.

The name latens derives from the Latin adjective meaning hidden, secret, not revealed. This term refers to the discovery of Iberian populations, previously cited as Merodon clavipes, as distinct species. Species epithet to be treated as an adjective.