Merodon aenigmaticus Vujić, Radenković & Likov, 2024

Vujić, Ante, Radenković, Snežana, Likov, Laura, Tubić, Nataša Kočiš, Popov, Grigory, Gilasian, Ebrahim, Djan, Mihajla, Milosavljević, Marina Janković & Ačanski, Jelena, 2024, Revisions of the clavipes and pruni species groups of the genus Merodon Meigen, 1803 (Diptera, Syrphidae), ZooKeys 1203, pp. 1-69 : 1-69

Merodon aenigmaticus Vujić, Radenković & Likov sp. nov.

Figs 1 A , 3 A , 4 G , 7 A , 9 , 12 C

Type material examined.

Holotype. Male in MNHN. The specimen had no label or information about its origin. FSUNS ID 04325 .

Diagnosis

(only male known). Similar to Merodon vandergooti (Fig. 4 C ) from which differs with less broad metafemur (in M. aenigmaticus sp. nov. is ~ 3.5 ×, while in M. vandergooti is ~ 2.5 × longer than wide) (Fig. 4 G ), less curved metafemur and metatibia (Fig. 4 G ), and quite rounded posterior surstylar lobe (Fig. 9 A : pl, marked with red arrow), while posterior surstylar lobe is strongly angulated ventrally in M. vandergooti (Fig. 10 A : pl, marked with red arrow). It differs from M. rufofemoris sp. nov. by partly black femora (Fig. 4 G ) (orange-yellow in M. rufofemoris sp. nov.; Fig. 4 E ), and quite rounded posterior surstylar lobe (Fig. 9 A : pl) (strongly angulate ventrally in M. rufofemoris sp. nov.; Fig. 11 A : pl, marked with red arrow).

Description.

Male. Head. Basoflagellomere orange-yellow (Fig. 12 C ), elongated, ~ 2 × longer than wide, and ~ 2.2 × longer than pedicel, convex dorsally; fossette dorsolateral; arista reddish to brown and thickened at basal third; arista ~ 1.5 × longer than basoflagellomere; face and frons black with whitish pollinosity, while face covered with dense whitish pilosity; pile on frons dense, greyish white; oral margin small, black, sparsely pollinose; lunula shining black to brown, bare; eye contiguity ~ 12 facets long; vertical triangle isosceles, black, shiny, except grey pollinose anterior corner, covered with greyish white pilosity; ocellar triangle equilateral; occiput with a grey-yellow pile, densely covered with grey pollinosity along eyes; eyes covered with short, whitish grey pile (Fig. 12 C ).

Thorax. Scutum and scutellum black with bronze lustre, covered with short, reddish yellow pile; pilosity between wing bases mostly black; scutum with indistinct pollinose vittae; posterior margin of scutellum with very long reddish yellow to whitish pilosity, reduced medially (Fig. 3 A ); posterodorsal part of anterior anepisternum, posterior anepisternum (except anteroventral angle), anterior anepimeron, dorsomedial anepimeron, and posterodorsal and anteroventral parts of katepisternum with long, dense greyish white pile; wings mostly covered with microtrichia; wing veins yellowish to brown; calypteres whitish yellow; halteres yellowish; legs reddish yellow, except black basal half of pro- and mesofemora, and basal 4 / 5 of metafemur; metafemur broad, covered with long, whitish yellow pilosity (Fig. 4 G ).

Abdomen. Elongated (Fig. 1 A ), ~ 1.3 × longer than mesonotum; terga black, except lateral sides of tergum 2 with reddish yellow maculae; terga 2–4 with broad, distinct silver-grey pollinose fasciate maculae interrupted medially; pile on terga reddish yellow to whitish; sterna black, covered with whitish grey pile; posterior margin of sternum 4 with characteristic posteromedial incision (Fig. 7 A ).

Male genitalia (Fig. 9 ). Anterior surstylar lobe large, elongated (up to 3 × longer than wide) and sickle-like (Fig. 9 A : al); posterior surstylar lobe rectangular with quite rounded ventral margin (Fig. 9 A : pl), ~ 1.5 × longer than wide, covered with short pile; cercus rectangular (Fig. 9 B : c); hypandrium sickle-shaped, without lateral projections; lingula short and tapering (Fig. 9 D : l).

Female. Unknown.

Distribution.

Unknown. The species is described based on a male holotype from the MNHN collection lacking any label or information about the origin of the specimen.

Etymology.

The name aenigmaticus derives from the Latin adjective, meaning ‘ enigmatic, like an enigma’, in the masculine form. This term describes the absence of any information related to the holotype, including collecting place, date or collector. Species epithet to be treated as an adjective.

Merodon clavipes ( Fabricius, 1781)

Syrphus clavipes Fabricius, 1781: 427 .

Musca clauda Villers, 1789: 463 .

Musca curvipes Gmelin, 1790: 2871 .

Syrphus gravipes Rossi, 1790: 286 .

Merodon curvipes Meigen, 1803: 274 .

Merodon senilis Meigen, 1822: 356 .

Merodon canipilus Rondani, 1865: 131 .

Merodon clavipes var. alba Paramonov, 1926: 90 .

Merodon clavipes var. atra Paramonov, 1926: 91 .

Merodon clavipes var. niger Paramonov, 1926: 90 .

Merodon clavipes albus Peck, 1988: 169 (sic! non Paramonov), syn. nov.

Merodon clavipes ater Peck, 1988: 169 (sic! non Paramonov), syn. nov.

Merodon clavipes niger Peck, 1988: 169 (sic! non Paramonov), syn. nov.

Merodon splendens Hurkmans, 1993: 182 , syn. nov.

Syrphus clavipes Fabricius, 1781: 427

Type locality. Italy. The original description ( Fabricius 1781) was based on an unspecified number of syntypes. The lectotype was designated by Hurkmans (1993: 178): male in Sehestedt and Tonder Lund collection ( ZMUC). Unfortunately, the type material was destroyed (AV pers. obs.). Two pins from the type collection possess only labels: [ Syrphus clavipes ] and [P 195-1].

Neotype (designated here). Male , Italy, Sicily, 20. vi. 1914, leg. Trautmann ( ZMUC).

A neotype was designated to clarify the taxonomic status of Merodon clavipes . Lectotype was designated by Hurkmans (1993) in his revisionary work on genus Merodon , but has been destroyed. Data and description are sufficient to ensure recognition of the specimen designated, and the neotype is consistent with what is known of the former name-bearing type from the original description and latter revision. Neotype belongs to the same country ( Italy) cited as the original type locality and it is deposited in the same Museum where lectotype was kept ( ZMUC).

Musca clauda Villers, 1789: 463

Type locality. France. Synonymy with Merodon clavipes was cited in Peck (1988: 168) and Hurkmans (1993: 178). Type material presumably lost.

Syrphus gravipes Rossi, 1790: 286

Type locality. Italy. Synonymy with Merodon clavipes was cited in Peck (1988: 168) and Hurkmans (1993: 178). Type material presumably lost.

Merodon senilis Meigen, 1822: 356

Type locality. Italy. Synonymy with Merodon clavipes was cited in Peck (1988: 168) and Hurkmans (1993: 178). Lectotype was designated by Hurkmans (1993: 178): female “ senilis ” ( NHMW) (not found).

Merodon canipilus Rondani, 1865: 131

Type locality. Italy. Synonymy with Merodon clavipes was cited in Peck (1988: 168) and Hurkmans (1993: 178). Lectotype was designated by Hurkmans (1993: 178): male in Rondani collection [52] ( LSF) (examined).

Merodon clavipes var. alba Paramonov, 1926 а: 90

Merodon clavipes albus Peck, 1988: 169 (sic! non Paramonov), syn. nov.

Holotype (examined). Female with labels: white, handwritten, bold ink [N 327]; yellowish, handwritten, pale ink, with bluish typographical frame [Valegotsulovo / d. Balta / g. Odessa / 2. vi. 25], 47.566923; 29.9389105, Ukraine; pink, handwritten, pale ink, with double typographical frame [ Merodon / clavipes Fabr. / var. alba ♀ / Typus var. nov.] ( SIZK).

Notes. This taxon was described from a single female, but the specimen storage location was not indicated ( Paramonov 1926 a: 90) and, until recently, it was not known ( Liepa 1969: 4, 20; Hurkmans 1993: 179 “ types of either of the varieties ... are considered to be lost ”, 205 “ lost ”, 206). The original description is based on a single specimen, which is the holotype according to article 73.1. 2 ICZN (1999) and it is kept in the SIZK collection ( Popov 2011). Type locality: Ukraine. The species name is clearly infrasubspecific (1.3. 4, 10.2 ICZN 1999) because, as stated by Paramonov himself, the specimen was collected together with the nominal taxon (45.6. 1, 45.6. 4 ICZN 1999, also see Lingafelter and Nearns 2013). Therefore, this name is not subject to Code 45.6.4.1 ( ICZN 1999). The name was first given subspecies rank in Peck’s Catalogue (1988: 169), i. e., « M. clavipes albus Paramonov » (the original gender ending was incorrect and changed, see Article 34.2, ICZN 1999), according to article 45 (g) (ii) ICZN (1985), now corresponding to 45.6. 4 ( ICZN 1999) (see 45.6.4.1 of ICZN, 1999). However, this is a violation of article 45 (f) (ii) ICZN (1985), now corresponding to 45.6. 1, 45.6. 4 ( ICZN 1999). According to article 45.5. 1 ( ICZN 1999), Peck adopts authorship of this species name, so we present it as Merodon clavipes albus Peck, 1988 , which is a syn. nov. for M. clavipes ( Fabricius 1781) . Later, Hurkmans (1993: 178) erroneously indicated that Peck (1988: 169) listed the name as a “ variety ”. He also erroneously indicated that S. Ya. Paramonov published the name in 1927 and that the single specimen is a syntype. He left the ranking “ variety ” for the name ( Hurkmans 1993: 179). Colour varieties of M. clavipes have been found in multiple populations of this species, similar to the variations reported for Merodon equestris ( Conn 1976; Han et al. 2018).

Merodon clavipes var. atra Paramonov, 1926 а: 91

Merodon clavipes ater Peck, 1988: 169 (sic! non Paramonov), syn. nov.

Notes. This variety was established without reference to the type material, for the male specimens that were in the possession of P. Sack ( Germany, now his collection is conserved in the Naturmuseum Senckenberg, Frankfurt am Main) ( Paramonov 1926 a: 91). The number of types was not given in the original description and their storage location was not indicated, nor were they discovered subsequently ( Liepa 1969: 4, 20). The type locality is also unknown. The types of this variety were also not found in the SIZK Department of Entomology collection (G. Popov, in prep.), where the vast majority of Paramonov’s types are stored. Thus, the types are considered lost, as already indicated by W. Hurkmans (1993: 178, 179, 205).

The name “ atra ” by Paramonov is clearly infrasubspecific (see Articles 1.3. 4 and 10.2, ICZN 1999), because S. Paramonov (Paramonov 1926 а) placed this variety together with others he described for this species (see Articles 45.6. 1 and 45.6. 4, ICZN 1999). Moreover, he did not report the type locality (see the same Articles; also see Lingafelter and Nearns 2013). Therefore, this name is not subject to the Code (see Article 45.6, ICZN 1999).

The name was given subspecies rank for the first time (see Article 45.6.4.1, ICZN 1999), « M. clavipes ater Paramonov » (the original gender ending was incorrect and changed, see Article 34.2, ICZN 1999), in Peck’s Catalogue (1988: 169) according to article 45 (g) (ii) ICZN (1985), now corresponding to Article 45.6. 4 ( ICZN 1999). However, this is a violation of Article 45 (f) (ii) ICZN (1985), now corresponding to Articles 45.6. 1 and 45.6. 4 ( ICZN 1999). So, according to the Articles 45.5. 1 and 50.3. 1 ( ICZN 1999), L. Peck established her own authorship of this name, and we use subspecies name ater Peck, 1988 that we consider to be a new synonym (syn. nov.) for M. clavipes ( Fabricius, 1781) , since according to our data, this colour form has no geographical reference and is inherent to some specimens of the species throughout the range. Colour varieties of M. clavipes have been found in multiple populations of this species, similar to variations described for Merodon equestris ( Conn 1976; Han et al. 2018).

Merodon clavipes var. nigra Paramonov, 1926 а: 90

Merodon clavipes niger Peck, 1988: 169 (sic! non Paramonov), syn. nov.

Holotype (examined). Female with labels: white, handwritten, bold ink [N 328]; yellowish, handwritten, pale ink, with bluish typographical frame [Valegozulovo / d. Balta / g. Odessa / 28. v. 25.], 47.566923; 29.9389105, Ukraine; pink, handwritten, pale ink, with double typographical frame [ Merodon / clavipes Fabr. / var. nigra ♀ / Typus. var. nov.] ( SIZK).

Notes. The situation for variety niger is identical to that described above for variety alba (see above clavipes var. alba Paramonov, 1926 ). The taxon was described from a single female, but the specimen storage place was not indicated ( Paramonov 1926 a) and, until recently, it was not known ( Liepa 1969; Hurkmans 1993). The original description is based on a single specimen, which is the holotype that is kept in the SIZK collection ( Popov 2011). Type locality: Ukraine. This name is clearly infrasubspecific because, as indicated by Paramonov himself, the specimen was collected together with the nominal taxon. Therefore, this name is not subject to Code 45.6.4.1 ( ICZN 1999). The name was given subspecific rank for the first time in Peck’s Catalogue (1988), i. e., « M. clavipes niger Paramonov » (the original gender ending was incorrect and changed, see Article 34.2, ICZN 1999). Thus, Peck assumes authorship of this name, so we use Merodon clavipes niger Peck, 1988 , which is a syn. nov. for M. clavipes ( Fabricius, 1781) . Later, Hurkmans (1993) mistakenly indicated that Peck (1988) listed the name as a “ variety ”, that Paramonov published the name in 1927, and that the single specimen is a syntype. He left the rank variety for the name ( Hurkmans 1993). Colour varieties of M. clavipes have been found in multiple populations of this species, similar to variations described for Merodon equestris ( Conn 1976; Han et al. 2018).

Figures

Figure 1. Body of male A M. aenigmaticus sp. nov. B – C M. clavipes D, E M. latens sp. nov. B, D dorsal view A, C, E lateral view. Scale bar: 2 mm.

Figure 3. Thorax of male, dorsal view A M. aenigmaticus sp. nov. B M. latens sp. nov. C M. rufofemoris sp. nov. Scale bar: 1 mm.

Figure 4. Metaleg of male, lateral view A M. clavipes B M. latens sp. nov. C M. vandergooti D M. quadrinotatus E M. rufofemoris sp. nov. F M. velox G M. aenigmaticus sp. nov. Scale bar: 1 mm.

Figure 7. Sternum 4 of male, dorsal view A M. aenigmaticus sp. nov. B M. clavipes C M. latens sp. nov. D M. quadrinotatus E M. rufofemoris sp. nov. F M. vandergooti G M. velox. Scale bar: 1 mm.

Figure 9. Male genitalia M. aenigmaticus sp. nov. A surstylar lobe B cercus C posterior surstylar lobe D hypandrium. Rounded posterior surstylar lobe marked with red arrow. A, B, D lateral view C ventral view. Abbreviations: al-anterior surstylar lobe, c-cercus, l-lingula, pl-posterior surstylar lobe. Scale bar: 0.5 mm.

Figure 10. Male genitalia M. vandergooti A, B epandrium, C hypandrium. A, C lateral view B ventral view. Strongly angulated ventral part of posterior surstylar lobe marked with red arrow. Abbreviations: al-anterior surstylar lobe, pl-posterior surstylar lobe. Scale bar: 0.5 mm.

Figure 11. Male genitalia M. rufofemoris sp. nov. A, B epandrium C hypandrium A, C lateral view B ventral view. Strongly angulated ventral part of posterior surstylar lobe marked with red arrow. Abbreviations: al-anterior surstylar lobe, c-cercus, l-lingula, pl-posterior surstylar lobe. Scale bar: 0.5 mm.

Figure 12. Head, frontal view A, B M. latens sp. nov. C M. aenigmaticus sp. nov. D M. rufofemoris sp. nov. A, C – D male B female. Scale bar: 1 mm.