Contributions to Zoology, 84 (4) – 2015Zorica Nedeljković; Jelena Ačanski; Mihajla Đan; Dragana Obreht-Vidaković; Antonio Ricarte; Ante Vujić: An integrated approach to delimiting species borders in the genus Chrysotoxum Meigen, 1803 (Diptera: Syrphidae), with description of two new species

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Appendix

Descriptions of new species

next section

Two new species of the vernale complex are described in the present study, and the species C. vernale is re-defined. The three studied species shared an antenna with the basoflagellomere shorter than scape and pedicel together and abdominal terga with yellow fasciae not reaching the lateral margins.

Family Syrphidae

Genus Chrysotoxum Meigen, 1803

Chrysotoxum montanum Nedeljković & Vujić sp. nov.

(= morphotype B sensu Nedeljković, 2011)

(Figs 8b, 11a, 13a)

FIG2

Fig. 8. Thoracic scutum of males, lateral view. A, Chrysotoxum vernale; B, Chrysotoxum montanum sp. nov.

Holotype. male, SERBIA, Kopaonik, Klisura Samokovske reke-mešano, 16.vi.2012, leg. A. Vujić (G1530, C104).

Paratypes. AUSTRIA: 1m, Frankenfels, 6/78, Bgst, (S11479), (NHMW); Bosnia & Herzegovina: 2m, Igman-Bjelašnica, 26.vi.1989. (S11301, S11302); 1m, Jahorina, 26.vi.1989. (S11300); Montenegro: Durmitor, 1m, Crepulj poljana, 4.vii.1991. (S11361), 1m, Crno jezero, 21.vi.1983. (S11324), 3m, do Male Karlice, 13.VII.1981. (S11358, S11359, S11360), 3m, do Zminjeg jezera, 3.VII.1981. (S11352, S11353, S11354), 3f, Ivan Do, 16.VIII.1984. (S11328), 27.VI.1993. (S11329, S11330); 1m, 1f, Jablan jezero, 20.VII.1995. (S11346, S11347); 4m, ka Jablan jezeru, 7.VII.1991. (S11342, S11343, S11344, S11345); 10m, ka Savinom kuku, 11.VII.1981. (S11305, S11306, S11307, S11308, S11311, S11313, S11309, S11310, S11312, S11314), 4m, Kanjon Sušice, 6.VII.1994. (S11337, S11341), 9.VII.1991. (S11338, S11327), 8m, Mlinski potok, 3.VII.1991. (S11321, S11322, S11323), 6.VII.1983. (S11315, S11316), 22.VI.1985. (S11317, S11318, S11319), 2m, 2f, Motički gaj, 9-10.VII.1983. (S11320, S11355, S11356, S11357), 1m, 1f, Otoka Crnog jezera, 24.VI.1983. (S11325, S11326) 1f, Pirlitor-Tara, 25.VI.1983. (S11363), 1m, Pitomine, 1.VII.1983. (S11362), 1f, Razvršje, 21.VIII.1984. (S11364), 2m, Sušica, 28.VI.1985. (S11334, S11335), 2m, 1f, Sušica-Skakala, 25-26.VI.1997. (S11366), 29.VI.1993. (S11339, S11340), 4m, Sušičko jezero, 25.VI.1985. (S11331, S11332, S11333), 25-27.VI.1986. (S11336), 5m, 2f, Sušičko jezero-Sastavci, 2.VI.1998. (S11365, S11370), 20.VI.1998. (S11367, S11368, S11369, S11371, S11372), 1m, Tepca, 6.VII.1983. (S11348), 3m, Tepca-kanjon Tare, 21.VI.­1983. (S11349, S11350, S11351); SERBIA: Kopaonik, 1m, 1f, Bačište, 4.VII.1986. (S06423, S06321), 2m, do Jablanove ravni, 23.VI.1991. (S06416, S06417), 2m, Duboka reka, 6.VII.1986. (S06420), 18.VII.1986. (S06421), 1f, Jablanova ravan, 20.V.1986. (S06390), 2m, Jasle-Jablanova ravan, 14.VI.1986. (S11444, S06418), 1m, 1f, Jasle-Čukara, 20.VI.1996. (S06415), 23.V.1993. (S06419), 1m, Kadijevac, 21.VI.1991. (S06422), 27m, 1f, Samokovska reka, 5.VII.1986. (S06402), 14.VIII.1997. (S06389), 16.VI.1986. (S06395, S06396, S06409, S06406, S06388, S06410, S06397, S06398, S06399, S06401, S06400, S06394), 19.VI.1996. (S06392, S06393), 21.VI.1991. (S06403), 22.V.1986. (S06407), 22.VI.1991. (S06404, S06405, S06386, S06411, S06412), 24.V.1992. (S06413, S06387), 24.V.1993. (S06391), 27.V.1994. (S06406, S06414), 1f, Treska - bukva, 17.VII.1985. (S06425), 1f, Velika reka, 14.VI.1986. (S06424), 1m, Klisura Samokovske reke-mešano, 16.VI.2012. (G1531/C105); Prokletije, 1m, ka Volušnici, 29.VII.1994. (S06385); Šar planina, 1m, Muržica, 12.VII.1996. (S06426); 3m, Ošljak, 29.VI.1988. (S06427, S06428, S11445).

Diagnosis. Medium to large species (15-17 mm, n = 10); r = 1:0.8:1.8; vertical and frontal triangles with black pile; scutum with black pile (Fig. 8B); katepisternum completely black (Fig. 9C) or with a very small yellow macula; scutellum with long black pile; male genitalia very similar to that in C. vernale ; surstylus 1.3 times longer than hypandrium (excluding superior lobes and aedeagus); epandrium plus surstylus 1.2-1.3 times longer than hypandrium (excluding superior lobes and aedeagus); in female frons black, with two triangular pollinose maculae. Chrysotoxum montanum has longer wings than C. vernale. Chrysotoxum montanum occurs only at high altitude. ML tree based on mtDNA COI gene revealed a clear separation of C. montanum from C. vernale.

Description. Male (holotype). L = 15 mm.

Head. Eye pile straight and yellow, denser and longer on the dorsal surface; vertical triangle black, with long black pile and white pollinosity on the posterior corners; frontal triangle black, shiny except for the white pollinosity posteriorly, black haired; antenna black; scape and pedicel with black pile; arista bare, dark brown; r = 1:0.8:1.8; face yellow, yellow haired on the lower part and black haired on the upper part; face with a central black vitta extending from antennal bases to mouth edge (vitta as wide as a fourth of the face width); mouth edge narrowly black; gena shiny yellow and yellow-haired; occiput white pollinose, with long black pile.

Thorax. Scutum black with two central, silvery-pollinose vittae extending for two thirds of the scutum length from its anterior margin; scutum with both long and short black pile intermixed (Fig. 8B); katepisternum completely black (Fig. 9C); scutellum yellow except for a black central disc and lateral corners, with long black pile; legs yellow except for the black basal third of femora; wing membrane extensively microtrichose; wing cells R1 and R2+3 brown pigmented.

Abdomen. Shiny black, with short black pile, except for the yellow-haired tergum 1 and anterior part of tergum 2; all terga with two yellow fasciae not reaching the lateral margins (Fig. 11A); all terga with black pile except for the yellow pile on the fasciae; all sterna shiny black and with yellow pile; anterior margin of sternum 3 with two interconnected yellow fasciae reaching the lateral margins; anterior margin of sternum 4 with two yellow maculae reaching the lateral margins.

Genitalia. Surstylus 2.5× longer than wide (Fig. 13A); triangular-shaped hypandrium, 1.5× longer than its basal width; surstylus 1.27-1.33 times longer than hypandrium (excluding superior lobes and aedeagus).

Female. Similar to the male except for the following characters: frons with two triangular maculae of silvery pollinosity; frons and scutum with short black pile.

Geographic distribution. Austria, Bosnia & Herzegovina, FYR Macedonia, Montenegro, Serbia (Fig. 14A).

Etymology. The epithet montanum means ‘belonging to a mountain’ and refers to the fact that this species is associated with mountain habitats.

Flight period. Early May to late August.

Habitat and flowers visited. This species has been found with other Chrysotoxum species in the grassy edges of conifer forests at high altitudes. Flowers visited: no data.

Taxonomic notes. In this new species, the katepisternum colour ranges from completely black (Fig. 9C) to black with a small yellow macula anteriorly. Chrysotoxum montanum sp. nov. can be separated from C. orthostylum sp. nov. and C. vernale by the colour of the long pile on the scutum, which are black in C. montanum sp. nov. (Fig. 8B) and yellow in the other species. For further morphological differences between C. montanum sp. nov. and C. vernale see Table 2.

FIG2

Table 2. Diagnostic comparison between C. montanum sp. nov. and C. vernale based on traditional morphology.

Chrysotoxum orthostylum Vujić sp. nov.

(Figs 9a, 10a, 10b, 11b, 12a, b; 13b)

FIG2

Fig. 9. Thoracic pleura, lateral view. A, Chrysotoxum orthostylum sp. nov.; B, Chrysotoxum vernale; C, Chrysotoxum montanum sp. nov. Dotted areas indicate yellow colour (kepst, katepisternum).

Holotype. male, FYR МАCEDONIA, Golema poljana, 14.VI.1975, leg. S. Glumac, (S11248), (FSUNS).

Paratypes. Kyrgyzstan: 1m, Tash-Arik, Talas, 4.VI.1992, leg. Jirousek, (S11448) (DD); FYR MACEDONIA: 3m, Kočani, vlažna livada, na lišću Lapsana - Chrysanthemum, 3.VI.1960, leg. Glumac (S11246, S11251, S11448); 1m, NP Pelister, 24.VII.1956. (S11247); 1f, Carevec, Bistra planina, 1.VII.1972, leg. Ćingoc (S11249); 1m, Kožuf, Golema poljana, 14.VI.1975 (S11248); 1m, Goten planina, 27.V.1988, leg. Krpač (S11252); 1m, 2f, Mavrovo, Carevec, 17.VI.1994, leg. Mihajlova (S11250, S11253, S11254); MONTENEGRO: 1m, Durmitor, Kanjon Sušice, 6.VII.1994, leg. Radenković (S11447); SERBIA: 1m, Kopaonik, Samokovska reka, 22.VI.1991, (S06316); TURKEY: 1m, Gurun, Mezikiran Gecidi, 10.VII.1997, leg. Mazıkıran Geçidi (S11245).

Diagnosis. Large to medium size species (14-17 mm, n = 9); r = 1:0.9:1; scutum with short black pile which are either intermixed with long yellow pile (male) or not (female); katepisternum with a yellow macula extending on most of its dorsal margin (Fig. 9A); posterior corners of terga 3 and 4 developed in thorn-like processes (Fig. 12A); male surstylus elongate, 3.7× longer than wide (Fig. 13B); surstylus as long as hypandrium (excluding superior lobes and aedeagus) (Fig. 10A); epandrium plus surstylus 1.5-1.6 times longer than hypandrium (excluding superior lobes and aedeagus) (Fig. 10A); in female frons black, with two rectangular pollinose maculae.

Highly significant differences in wing shape were shown between C. orthostylum sp. nov. and C. vernale and C. montanum sp. nov. mtDNA COI haplotype of C. orthostylum sp. nov. is genetically the most divergent to C. vernale and C. montanum sp. nov.

FIG2

Fig. 10. Male genitalia. A, Chrysotoxum orthostylum sp. nov., lateral view; B, Chrysotoxum orthostylum sp. nov., dorsal view; C, Chrysotoxum festivum, lateral view; D, Chrysotoxum festivum, dorsal view; E, Chrysotoxum vernale, lateral view; F, Chrysotoxum vernale, dorsal view.

Description. Male (holotype). L = 14.5mm.

Head. Eye pile straight and yellow, denser and longer on the dorsal half of the eye surface; vertical triangle black, with black pollinosity on the anterior corner and silvery-white pollinosity posteriorly, black-haired except for some yellow pile anteriorly; eye contiguity about 17-facets long; frontal triangle black, with long, black and yellow pile intermixed; antenna black, with black pile on scape and pedicel; arista dark brown and bare; r = 1:0.9:1; face tuberculated, yellow and yellow-haired; face with a central black vitta extending from antennal bases to mouth edge (vitta as wide as a fourth of the face width); genae yellow with yellow pile; occiput white pollinose, with long yellow pile.

Thorax. Scutum black with two central, silvery-pollinose vittae extending for two thirds of the scutum length from its anterior margin; scutum with long yellow pile, intermixed with short black pile on the posterior part; katepisternum with a yellow spot on the dorsal margin (Fig. 9A); scutellum yellow with a black central disc, covered with long yellow and short black pile; legs yellow except the black basal third of pro- and mesofemora; leg pile yellow; wing wholly microtrichose; halter completely yellow; cells R1 and R2+3 brown pigmented.

Abdomen. Elongate, parallel-sided (Fig. 11B); shiny black with short black pile, except for the yellow-haired tergum 1 and anterior part of tergum 2; all terga with two yellow and yellow-haired fasciae (Fig. 11B); posterior corners of terga 3 and 4 developing in thorn-like processes (Fig. 12A); all sterna shiny black and yellow haired; anterior margin of sternum 3 with two interconnected yellow fasciae not reaching the lateral margins; anterior margin of sternum 4 with two yellow maculae not reaching the lateral margins.

FIG2

Fig. 11. Abdomen, dorsal view. A, Chrysotoxum montanum sp. nov.; B, Chrysotoxum orthostylum sp. nov.; C, Chrysotoxum vernale.

Genitalia. (Fig. 10A, B): Elongate surstylus, 3.7× longer than wide (Fig. 13B); triangular-shaped hypandrium, 1.2 times longer than its basal width (Fig. 10A).

Female. Similar to the male except for the following characters: frons black with two rectangular pollinose maculae; frons with short black pile; scutum only with short black pile.

Geographic distribution. FYR Macedonia, Kyrgyz­stan, Montenegro, Serbia, Turkey (Fig. 14B).

Etymology. The noun in apposition orthostylum means ‘straight stylus’ and refers to the fact that the male surstylus is straight and more elongated than that in similar species.

Flight period. Mid May to mid August.

Habitat and flowers visited. Chrysotoxum orthostylum sp. nov. has been found flying with other Chrysotoxum species in the grassy edges of conifer forests at high altitudes in Serbia and Montenegro. In FYR Macedonia, C. orthostylum sp. nov. has been found resting on Lapsana and Chrysanthemum leaves in wet meadows.

Taxonomic notes. Chrysotoxum orthostylum sp. nov. can be distinguished from C. montanum sp. nov. and C. vernale by the abdomen shape, which is slender and nearly parallel-sided in C. orthostylum sp. nov. (Fig. 11B) but more oval in other species (Fig. 11A, C). In addition, the posterior corners of tergites 3 and 4 in C. orthostylum sp. nov. are developed into thorn-like processes (Fig. 12A, B), while in similar species these corners are blunter. The katepisternum of C. orthostylum sp. nov. has a yellow macula (Fig. 9A), which is more reduced or even absent in C. vernale and C. montanum sp. nov. (Fig. 9B, C). Males of C. orthostylum sp. nov. can be separated from other species by the long surstylus, which is 3.3-3.7× (n = 5) longer than wide in C. orthostylum sp. nov. (Fig. 13B) but 2.8× or less in the other species (Fig. 13A, C). In addition, the shape of the hypandrium apex is rectangular in C. orthostylum sp. nov. (Fig. 10A) and more triangular in C. festivum (Fig. 10C) and C. vernale (Fig. 10E).

Variability. In C. orthostylum sp. nov. the colour of legs ranges from dark yellow to black in basal third of pro- and mesofemora and in basal two thirds of metafemora. In addition, southern specimens (FYR Macedonia) have wider and lighter yellow fasciae on terga than specimens from more localities further north.

FIG2

Fig. 12. Terga 3-5, dorsal view, Chrysotoxum orthostylum sp. nov. A, male; B, female (t, thorn-like process).

FIG2

Fig. 13. Right surstylus of the male genitalia, lateral view. A, Chrysotoxum montanum sp. nov.; B, Chrysotoxum orthostylum sp. nov.; C, Chrysotoxum vernale.

Chrysotoxum vernale Loew, 1841

(= morphotype A sensu Nedeljković, 2011)

(Figs 8a, 9b, 10e, 10f, 11c, 13c)

syn. collinum Rondani, 1857: 202

syn. flavipenne Palma, 1864: 40

syn. fuscum Giglio-Tos, 1890: 160

syn. vernaloides Giglio-Tos, 1890: 161

Chrysotoxum vernale was described from an unspecified but large (“Unter vielen Exemplaren...”) number of specimens, both males and females. Some males studied by Hermann Loew were collected in the place where he was working at the time of the description (“...hier gefangen...”): Poznań (“Posen”), Poland. Apart from this, no other data about the type locality of C. vernale are given in the original description. In the ZMHB there are 27 specimens of C. vernale belonging to Loew’s collection (J. Ziegler, in lit.); of these specimens only 20 are labelled as ‘Coll. H. Loew’ and further information is not provided in the available data bases at the ZMHB (Sven Marotzke, in lit.). These specimens were examined here to confirm the colour of scutum pile, which was yellow. Two named specimens (male and female) of C. vernale from the ‘old collection’ (“Alte Sammlung”) at the NHMW were also examined; the female is labelled as ‘Chrysotoxum vernale f Loew*’ (handwritten). No information about the locality where the NHMW specimens were collected is available, but Loew’s type material is usually marked with an asterisk (*) (A. Vujić, pers. obs.). We consider that the specimens examined both in ZMHB and NHMW belong to the type series of C. vernale and the NHMW male is designated as lectotype in order to stabilize this species concept.

Chrysotoxum flavipenne was described from a single male. The description provided by Palma (1863) is detailed enough and indicates that the scutum pile are yellow (“Torace...rivestito nel dorso da gialla peluria...”) and the thoracic pleuron has a yellow macula (“...ampia macchia triangolare dello stesso colore su ciascun fianco”). The repository collection of the C. flavipenne holotype is unknown to the authors of the present paper; it might be deposited in the entomological collection at the Museo Zoologico, Centro Musei delle Scienze Naturali, Naples, Italy but this collection is now being inventoried (Roberta Improta, in lit.). Giglio-Tos (1890) diagnosed Chrysotoxum fuscum and compared it with C. vernale of Loew. Giglio-Tos (1890) also noted the existence of Chrysotoxum vernaloides as a variety of C. fuscum. According to the original description of C. fuscum the colour of the scutum pile is yellow (“Thorace fulvo piloso”); the variety vernaloides differed from other C. fuscum specimens in characters other than the thoracic pile (Giglio-Tos, 1890). Sommaggio (2001) proposed C. fuscum and C. vernaloides as junior synonyms of C. vernale upon examination of the type material and designated lectotypes for these two names. These two lectotypes are deposited at the entomological collection of the Museo Regionale di Scienze Naturali, Torino, Italy. However, this museum suffered a fire in 2013 and the collections are still inaccessible to users; Giglio-Tos’ collection is undamaged (Marinella Garzena, in lit.). Based on the original descriptions of C. flavipenne, C. fuscum and C. vernaloides, as well as on the nomenclatural and taxonomic advances made by Sommaggio (2001), we confirm these three names as synonyms of C. vernale. In addition, the holotype of C. collinum was examined by the authors of the present study on the basis of four images made by Dr Luca Bartolozzi (LSF): dorsal, lateral and ventral overall views and anterior view of the face. This specimen was also confirmed to be the typical C. vernale.

Material examined.

Lectotype (designated here): 1m labelled as ‘vernale, Schlerin’/ ‘Alte Sammlung’ / S11470 (NHMW).

Paralectotypes (designated here). 1f labelled as 16/547/ vernale f Loew Alte Sammlung/ Austria Alte Sammlung/ Chrysotoxum vernale f Loew* (NHMW). 20 specimens labelled as ‘Coll H. Loew’ and seven specimens not labelled but supposed to be part of Loew’s collection and have been collected in Poznań (J. Ziegler, in lit.); 10 of the 20 ‘Coll H. Loew’ specimens are labelled as ‘Wien Schiner’ (4 specimens), ‘Florenz Mann’ (3 specimens), ‘Syrakus Zeller’ (1 specimen), ‘Spanien’ (1 specimen), ‘Paris’ (1 specimen) (ZHMB).

Additional material. Holotype of Chrysotoxum collinum: m, Museo “La Specola” coll. Rondani HOLOTYPUS (red label)/ 357/ Chrysotoxum vernale (= collinum Rnd.)/ rev. (overwritten by hand on ‘det.’) M. Daccordi 1985 [LSF]. For further non-type additional material see Table S1.

Diagnosis. Large to medium size species (11-15 mm, n = 10); r = 1:0.6:1.5; vertical and frontal triangle with yellow pile; scutum with long yellow pile (male) (Fig. 8A); katepisternum with a yellow macula (Fig. 9B); scutellum mainly with long yellow pile; basal third of pro- and mesofemora black; surstylus 1.2-1.3 times longer than hypandrium (excluding superior lobes and aedeagus) (Fig. 13C); epandrium plus surstylus 1.1-1.2 times longer than hypandrium (excluding superior lobes and aedeagus) (Fig. 10E); in female, frons black, with two rectangular pollinose maculae. Chrysotoxum vernale has larger wings than C. montanum. Additionally, it has wide temperature, precipitation and altitude range.

Geographic distribution. (only localities confirmed in the present study): Austria, Croatia, Finland, Germany, Greece, Italy, FYR Macedonia, Montenegro, Poland, Serbia (Fig. 14C).

Flight period. Mid April to mid-August.

Habitats and flowers visited. In Europe, C. vernale is found in the following habitats: forests; open woodlands and scrubs on well-drained sites, from Betula invaded heathland to Fagus woodlands to Genista florida/Quercus pyrenaica maquis; also in well-drained, unimproved grasslands, including montane and alpine grasslands (up to 2500 m). It is known to visit white flowers of Umbelliferae, as well as those of Caltha, Crataegus, Euphorbia, Helianthemum, Sorbus, Valeriana (Speight, 2013).

Taxonomic notes. To separate this species from the similar C. montanum sp. nov. see Table 2.

FIG2

Fig. 14. Distribution maps of the material examined. A, Chrysotoxum montanum sp. nov.; B, Chrysotoxum orthostylum sp. nov.; C, Chrysotoxum vernale.

Adjustments to the Palaearctic Chrysotoxum key

Refinements to couplets in the key to the Palaearctic Chrysotoxum in Violovitsh (1974) are provided below, based on the results presented here, as well as those in Nedeljković et al. (2013). Chrysotoxum montanum sp. nov., C. vernale and specimens of C. orthostylum sp. nov. with femora black basally would key out to C. vernale (sensu lato) in Violovitsh (1974); specimens of C. orthostylum sp. nov. with femora wholly yellow would key out to Chrysotoxum festivum (Linnaeus, 1758) (s. l.). Chrysotoxum festivum and Chrysotoxum tomentosum Giglio-Tos, 1890, which also have yellow fasciae on terga 2-4 not reaching the lateral margins of tergum, would key out to C. festivum (s. l.).

Chrysotoxum festivum, C. orthostylum sp. nov. (femora wholly yellow), and C. tomentosum

Males – change step 46

 

 

46 (47).

Femora of all legs yellow.

a (b).

Posterior corners of terga 3 and 4 developed into thorn-like processes (Fig. 12A); male surstylus elongate, 3.7× longer than wide (Fig. 13B)

C. orthostylum sp. nov.

b (a).

Posterior corners of terga 3 and 4 without or with very inconspicuous thorn-like processes; male surstylus 1.5-2.8× longer than wide.

c (d).

Scutum with long yellow pile only (figure 5A: Nedeljković et al., 2013); mouth edge yellow

C. festivum

d (c).

Scutum with long yellow pile and short black pile intermixed (figure 5B: Nedeljković et al., 2013); mouth edge black

C. tomentosum

Chrysotoxum montanum sp. nov., C. orthostylum sp. nov. (femora black basally), and C. vernale

Males – change step 47

 

 

47 (46).

Pro- and mesofemora dark brown to black at least basally.

a (b).

Abdomen slender, 1.8× longer than wide; posterior corners of terga 3 and 4 developed into thorn-like processes (Fig. 12A); male surstylus elongate, 3.7× longer than wide (Fig. 13B)

C. orthostylum sp. nov.

b (a).

Abdomen more oval, 1.4-1.6× longer than wide (Figs. 11A, C); posterior corners of terga 3 and 4 without or with very inconspicuous thorn-like processes; male surstylus 2.5-3× longer than wide (Figs. 13A, C).

c (d).

Scutum with yellow pile only (Fig. 8A); katepisternum with a yellow macula (Fig. 9B)

C. vernale

d (c).

Scutum with black pile only (Fig. 8B); katepisternum completely black (Fig. 9C)

C. montanum sp. nov.

Chrysotoxum festivum, C. orthostylum sp. nov. (femora wholly yellow), and C. tomentosum

Females – change step 36

 

 

36 (37).

Femora of all legs yellow.

a (b).

Abdomen slender, 2× longer than wide; posterior corners of terga 3 and 4 developed into thorn-like processes (Fig. 12B)

C. orthostylum sp. nov.

b (a).

Abdomen more oval, 1.6-1.7× longer than wide; posterior corners of terga 3 and 4 not developed into thorn-like processes, or very inconspicuously developed.

c (d).

Pollinose maculae on frons triangular

C. tomentosum

d (c).

Pollinose maculae on frons rectangular

C. festivum

Chrysotoxum montanum sp. nov., C. orthostylum sp. nov. (femora black basally), and C. vernale

Females – change step 37

 

 

37(36).

Pro- and mesofemora dark brown to black at least basally.

a (b).

Abdomen slender, 2× longer than wide; posterior corners of terga 3 and 4 developed into thorn-like processes (Fig. 12B)

C. orthostylum sp. nov.

b (a).

Abdomen more oval, 1.6-1.7× longer than wide; posterior corners of terga 3 and 4 not developed into thorn-like processes, or very inconspicuously developed.

c (d).

Pollinose maculae on frons triangular

C. montanum sp. nov.

d (c).

Pollinose maculae on frons rectangular

C. vernale