Regiscolia bidens ( Linnaeus, 1767 ), 2025

Regiscolia bidens ( Linnaeus, 1767) , comb. nov.

( Figs 69–71 View FIGURE 69 View FIGURE 70 View FIGURE 71 )

Sphex bidens Linnaeus, 1767: 943 ( holotype, ♀, Mauritania, deposited in LSL, United Kingdoms , not examined); Christ 1791:

255; Guiglia & Betrem 1958: 99. Scolia bimaculata Fabricius, 1781: 45 ; Rossi 1790: 70; Coquebert 1801: 55; Klug 1805: 24; Vander Linden 1827: 287

(synonymised by Lepeletier 1825: 523). Scolia emaculata Cyrillo, 1787: 2 (synonymised by Costa 1858: 8). Scolia flavicornis Lepeletier, 1825: 393 (synonymised in Micha 1927:135). Scolia ( Scolia) bimaculata : Guérin-Méneville 1830: 247. Scolia bidens : Lepeletier 1845: 523; Lucas 1849: 278; Saussure 1855: 36; Smith 1855: 111; Costa 1858: 7; Palma 1869: 34;

Saussure 1890: 188; Bartlett 1912: 338. Scolia ( Triscolia) bidens : Saussure & Sichel 1864: 52; Kirchner 1867: 212; Saunders 1901: 535; Gaulle 1908: 125; Vogrin 1915:

39-40; Berland 1925: 296–298; Betrem 1927b: 292; Guiglia 1928: 426, 435–436; Dusmet 1930: 20–21; Betrem 1933: 261;

Nadig & Nadig 1935: 4; Guiglia 1940: 277; Guiglia 1944: 147; Giner Mari 1945: 127; Guiglia 1951: 286; Steinberg 1962:

119; Mingo & Compte 1963: 76. Scolia ( Scolia , Triscolia ) bidens : Dalla-Torre 1897: 149. Triscolia bidens : Micha 1927: 134; Guiglia & Capra 1937: 82. Triscolia bidens bidens : Micha 1927: 134–136, 148, 150. Scolia ( Triscolia) bidens var. rufohirta Dusmet, 1930: 22 ; Guiglia 1951: 287; Mingo & Compte 1963: 76. Syn. nov. Megascolia ( Regiscolia) bidens : Betrem & Bradley 1964: 444; Bradley & Betrem 1964: 10; Nagy 1967: 222; Hamon et al.

1995: 18; Osten 1999a: 424; Osten 2000: 546, 551, 557; Osten 2002: 345, 349; Osten 2005b: 28; Demetriou et al. 2021:

20. Megascolia bidens : Nagy 1967: 222; Pagliano 1987: 163; Diniz 1991: 31; Hamon et al. 1995: 32; Castro 2011: 387; Baldock

2014: 343, 399; Samin & Baðrýaçýk 2012: 391; Samin et al. 2014: 716; Dvořák & Boščík 2017: 380; Baldock et al. 2020:

16; Turrisi et al. 2020: 722; Al-Azab 2020: 147. Regiscolia bidens : Argaman 1996: 188.

Material examined. Morocco. Marrakech-Safi region . 1♀, Idni , 17.V.1994 ( J.F. Vayssières leg.) [ CJBC]. Ouarzazate region . 1♀, Aït-Ben-Haddou, 24.V.2007 (local coll. leg.) [ CJBC]. Khémisset province . 5♀, Oulmès, 21.V.2015 (local coll. leg.) [ CJBC]. Rabat-Salé-Kénitra region. 1♀, El Arba, Route de Mrirt , 22.V.2014 ( J.F. Vayssières leg.) [ CFC]. Ifrane region . 1♂, Ben Smim, VI.2016 (local coll. leg.) [ CJBC]; 1♀ 1♂, Ifrane, 10.VI.2016 (local coll. leg.) [ CJBC]. Khénifra province . 1♂, Aguelmous, 18.V.2018 (local coll. leg.) [ CJBC]. Tinghir region. 1♂, Kelaat Mgouna, 15.V.2018 ( G.L. Agnoli leg.) [ CJBC]. Tiznit region. 1♀, Tafraout, 24.IV.2019 (local coll. leg.) [ CJBC] .

Spain. Seville province. 2♀ 3♂, Seville, 17.VII.2015 (local coll. leg.) [ CJBC]. Alicante province . 1♀ 1♂, Alicante, 10.VI.2024 (local coll. leg.) [ CJBC] . Tunisia. Nabeul governorate. 1♀, Cap Bon, VII.1956 (local coll. leg.) [ CJBC] . Tunis governorate. 2♂, El Marsa, 07.III.1957 (local coll. leg.) [ CJBC] . Gabès governorate. 1♀ 1♂ , Gabès, 21.V.2013 (local coll. leg.) [ CJBC] . Kasserine governorate. 1♀ 4♂, Sbeïtla, 18.IV.2014 (local coll. leg.) [ CJBC] .

Diagnosis. Regiscolia bidens ( Linnaeus, 1767) , comb. nov. differs from R. alecto (Smith, 1858) , comb. nov., R. azurea ( Christ, 1791) , comb. nov., R. capitata ( Fabricius, 1804) , comb. nov. and R. fulvifrons ( Saussure, 1855) , comb. nov. in females by having the apical part of scutum with a dense and uninterrupted band of punctures along the scutellum; the dorso-median area of propodeum short, approximately equal to the length of the metanotum; and the basal part of T2 with sparse punctures similar to those of the median part. In contrast, in Regiscolia azurea , R. capitata and R. fulvifrons , the apical part of scutum has sparser punctures medially or is impunctate, thus not forming a continuous band of punctures along the scutellum; the dorso-median area of propodeum is distinctly longer than the metanotum; and the basal part of T2 has finer and denser punctures forming a band, the median part being sparsely and coarsely punctate. In males, R. bidens differs by having the area around and between the posterior ocelli with very dense, tight, fine, and agglomerated punctures; and the length of the dorso-median area of propodeum nearly equal to that of the metanotum. In contrast, in R. azurea , R. alecto and R. fulvifrons , the area around and between the posterior ocelli has sparser and coarser punctures; and the length of the dorso-median area of propodeum is significantly greater than that of the metanotum. In both sexes, the wings of R. bidens are bicolored, yellowish in the cells and dark elsewhere. Whereas in Regiscolia azurea , Regiscolia alecto , R. capitata , Regiscolia fulvifrons and R. splendida , they are entirely dark.

R. bidens is easily distinguished from R. capitata ( Fabricius, 1804) , comb. nov. in both sexes by having the head with coarse and dense punctures; and the mesosoma entirely melanistic (sometimes scutellum orangish in female). In contrast, in R. capitata , the head is almost entirely impunctate with finer and sparser punctures; and the scutellum, metanotum, dorso-median area of propodeum are marked with yellow.

R. bidens is distinguished from R. almoraensis ( Gupta & Jonathan, 2003) , comb. nov., R. maculata ( Drury, 1773) , comb. nov., and R. rubida ( Gribodo, 1893) , comb. nov. in both sexes by having the upper margin of marginal cell shorter or almost equal to the lower margin. Whereas in R. almoraensis , R. maculata and R. rubida , the upper margin of marginal cell is significantly longer than the lower margin.

The males of R. bidens are the only ones with the flagellum entirely yellow. In all other Regiscolia species the flagellum is black, or at most brown to reddish.

Redescription. Female ( Fig. 69 View FIGURE 69 ). Length 23–26 mm.

Head ( Figs 69B, C View FIGURE 69 ). Mandibles long and slender. Median mandibular tooth small and prominent, sometimes blunt. Anterior margin of clypeus rounded, without prominent lateral lobes; disk of clypeus not-domed and reticulated apically; impunctate medially. Fissura frontalis weak, barely visible after the frontal spatium. Frons with dense punctures on the sides of the anterior ocellus, mostly impunctate in front of the anterior ocellus and near the eye notch. Vertex with dense punctures.

Mesosoma ( Fig. 69D View FIGURE 69 ). Pronotum fine and dense punctures, more space and coarse punctures close to the excavation of pronotum. Tegula with coarse punctures at base and along scutum. Scutum with fine, tight and dense punctures basally; with sparse and coarse punctures laterally, except for antero-lateral corners with dense and fine punctures; largely impunctate medially; with a fine, dense, and continuous band of punctures apically. Scutellum with fine and dense punctures basally; distinctly sparser and coarser medially. Metanotum with fine, tight and dense punctures, with a thin impunctate central band. Dorso-lateral area of propodeum with very dense, tight and fine punctures, without an impunctate area (mirror) anteriorly. Dorso-median area of propodeum with two protruding projections prolonged towards the rear; approximately equal to the length of the metanotum; with very fine, tight dense punctures. Upper plate of metapleuron with dense punctures on its upper third. Anterior margin of marginal cell shorter than posterior margin. Forewing with three submarginal cells. Hind tibiae spurs of similar length.

Metasoma ( Fig. 69E View FIGURE 69 ). T1 with a tubercle not depressed in the middle; with dense and fine punctures, more sparser basally. T2 with scattered and coarse punctures basally; with coarse and very sparse punctures medially; with very fine, tight and dense punctures apically. T3 almost entirely impunctate basally and medially; with dense, tight and fine punctures apically. T4 to T5 with similar punctation, but the central impunctate area gradually reduced. S1 with dense and fine punctures on sides, mostly impunctate on the rest. S2 without distinct tubercle; with fine and dense punctures basally; with sparse and coarse punctures medially; with dense and fine punctures apically, except in the middle apically with sparse punctures. S3 to S5 with similar punctation.

Coloration ( Fig. 69 View FIGURE 69 ). Integument predominantly black. Head marked with orange-red on frons and vertex; ocellar region yellow-orange. Antennae orange-red, except black scape and pedicel. Mesosoma black, scutellum often marked with orange-red and sometimes pronotum laterally close to the excavation of pronotum. Metasoma black, T2 and T3 marked with two yellow spots that never fuse. Legs black. Wings bicolored, yellowish in the cells, dark on the rest. Pilosity black, except in the colored areas.

Male ( Fig. 70 View FIGURE 70 ). Length 21–26 mm.

Head ( Figs 70B, C View FIGURE 70 ). Inner margin of mandible with three distinct tooth (third apical tooth sometimes blunt and barely visible). Disk of clypeus with sparse punctures apically, dense punctures basally and laterally. Fissura frontalis visible reaching anterior ocelli. Frontal cross-furrow visible, its extension reaching the upper part of the ocular sinus. Frontal spatium with dense, tight and fine punctures. Anterior ocelli depressed, larger than posterior ocelli. Frons with dense, fine and tight punctures, impunctate in front of the anterior ocellus. Vertex with fine, tight and dense punctures, particularly around the posterior ocelli.

Mesosoma ( Fig. 70D View FIGURE 70 ). Pronotum with dense, tight and fine punctures over its entire surface, inter-points spaces almost coalescent. Tegula with dense and coarse punctures anteriorly and along the scutum, largely impunctate near the wing. Scutum with very fine, coalescent and dense punctures in its anterior third; with dense and fine punctures on the rest. Scutellum with fine and dense punctures basally, sparser medially and mostly impunctate apically. Metanotum with fine and dense punctures laterally, impunctate line in the middle. Dorso-lateral area of propodeum without impunctate area (mirror) anteriorly; with fine, dense and tight punctures. Dorso-median area of propodeum with two protruding projections prolonged towards the rear; with very fine, tight dense punctures. Anterior margin of marginal cell shorter than posterior margin. Forewing with three submarginal cells.

Metasoma ( Fig. 70E View FIGURE 70 ). T1 with a strong tubercle; with dense, fine and tight punctures over its entire surface. T2 with fine, tight and dense punctures, slightly sparse medially. T3-T6 similarly punctate. S1 raised in the middle, with dense punctures medially. S2 without distinct tubercle; with dense, tight and fine punctures basally and laterally, sparser medially and apically. S3 with sparse punctures medially, more denser laterally. S4-S6 similarly punctate.

Coloration ( Fig. 70 View FIGURE 70 ). Head black, ocular sinus often orange reddish, yellow antennae except for the scape and pedicel. Mesosoma black. Metasoma black, T3 marked with two yellow spots never fused. Wings bicolored, yellowish in the cells, dark on the rest. Pilosity black, except in the colored areas, exceptionally with entire redbrownish pilosity.

Genitalia. See Fig. 31D View FIGURE 31 .

Distribution. Algeria, Egypt, Greece (continental and Dodecanese Islands), Israel, Italy (including Sicily), Libya, Malta, Morocco, Portugal, Romania, Spain (including the Balearic Islands), Tunisia (Dusmet 1930; Betrem 1933; Guiglia 1940; Mingo & Compte 1963; Nagy 1967; Valetta 1979; Pagliano 1987; Osten 2000; Osten 2002; Baldock 2014; Samin et al. 2014; Turrisi et al. 2020; Al-Azab 2020; Demetriou et al. 2021) ( Fig. 71 View FIGURE 71 ).

Samin et al. (2014) mentioned the presence of R. bidens from regions such as Arabian Peninsula, Armenia, Azerbaijan, Georgia, Iraq, Iran, Jordan, Lebanon, Russia, Syria, and Turkey; but these records are doubtful and considered to be erroneous ( Demetriou et al. 2021). Similarly, two French observations of the species in the Hérault department in France have been reported in the past ( Hamon et al. 1995). As these data are old and doubtful, they are not considered here.

Biology. Saussure (1890) reported Scolia bidens [= Regiscolia bidens ( Linnaeus, 1767) ] entering garden compost in search of Phyllognathus silenus [= Phyllognathus excavatus ( Forster, 1771) ] larvae. Other hosts have also been cited: Oryctes nasicornis laevigatus ( Heer, 1841) , Polyphylla fullo ( Linnaeus, 1758) and Lucanus cervus ( Linnaeus, 1758) ( Vereecken & Carrière 2003) .

Remarks. Regiscolia bidens has no known subspecies. Nevertheless, Dusmet (1930) described the variation rufohirta Dusmet, 1930 from two females from Spain (Sierra de Guadarrama and Cadiz). This taxon differs from the typical form mainly in its ferruginous red pilosity on the mesosoma, T1 and ventral part of the metasoma, while the legs are partially reddish. Guiglia (1951) also reports a female from Morocco (Midelt). We can also report two males from Tunisia (Marsa) showing the same variations. The same kind of pilosity and cuticle erythrism is observed in other Scoliidae species (notably within the genus Scolia , e. g. S. erythrocephala , S. flaviceps ), the degree of erythrism increases as one approaches hot desert regions. Scolia ( Triscolia) bidens var. rufohirta , syn. nov. is therefore synonymized with R. bidens .