Sphiximorpha subsessilis Illiger in Rossi 1807
Creators: name: Steenis, Jeroen Van
name: Ricarte, Antonio
name: Vujić, Ante
name: Birtele, Daniele
name: Speight, Martin C. D.
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Syrphidae
Sphiximorpha
Sphiximorpha subsessilis

description: Sphiximorpha subsessilis (Illiger in Rossi, 1807)
Figs 52, 55, 120, 121, 128, 129, 136, 137, 140, 147, 155, 156, 161–165, 172
Ceria subsessilis Illiger in Rossi, 1807: 446. Type locality: Italy [ST ♂ ZMHB].
Ceria subsessilis: Latreille (1809), Schiner (1857, 1862), Bezzi (1894, 1900), Strobl (1900).
Cerioides subsenilis, misspelling: Becker (1921), comb. nov.
Cerioides subsessilis: Shannon (1925), Sack (1932), Şuster (1959), Bańkowska (1963), van Doesburg (1953), Drensky (1934), Glumac (1972).
Sphiximorpha subsessilis: Rondani (1857) comb. nov., Speight (1984), Peck (1988), Brădescu (1986, 1989, 1991), van der Goot (1981), De Buck (1990), Röder (1990), Verlinden (1991), Maibach et al. (1992), Schmid (1993, 1994), Stuke (1993), Dirickx (1994), Speight (1994), Belcari et al. (1995), van Aartsen (1997), Dussaix (1997, 2007), Sarthou & Speight (1997), Malec et al. (1999), Ssymank et al. (1999), Jessat & Dziock (2000), Bartsch (2001b), Kehlmaier (2001), Dunk et al. (2003), Dziock et al. (2004), Kehlmaier & Martínes de Murguía (2004), Stuke et al. (2004), van Veen (2004), Speight et al. (2005), Stănescu & Pârvu (2005), Mason et al. (2006), Rotheray et al. (2006), Haarto & Kerppola (2007), Reemer & Smit (2007), Sommaggio (2007), Whitmore et al. (2008), Bartsch et al. (2009), Reemer et al. (2009), Vujić et al. (2009), Ricarte & Marcos-García (2010), Withers & Goy (2012), Radenković et al. (2013), Sarıbıyık (2014), Speight & Kime (2014), Burgio et al. (2015), Pétremand & Speight (2015).
Redescription. MALE (Figs 120, 128). Body length: 11.1–15.2 mm; wing length: 9.1–11.3 mm. Head (Fig. 136). Face protruding antero-ventrally with weakly demarcated tubercle and strongly concave below antennae. Head 1.9–2.1 times wider than face just below the antennae; length of eye contiguity 0.56–0.67 times as long as length of frons; angle of eyes at eye contiguity 140–155o. Face with yellow and black colour pattern; genae, mouth edge and hypostomal bridge black; broad rhombic formed medial black vitta; a broad black fascia at frontal prominence black. Frons yellow, sometimes with medial black vitta from frontal prominence to eye suture. Vertical triangle black to yellow. Ocellar triangle black. Dorsal surface of head capsule broadly yellow posterior of ocellar triangle, laterally yellow along eye margin and black posteriorly. Frontal prominence 0.69–0.76 times longer than wide; relative length of pedicel is as 1.1–1.2: 1: 1.0–1.1. Antennae dark-brown to black coloured; arista white pilose. Thorax. Scutum black with yellow macula on postpronotum and notopleuron, and sometimes with oval vittae posterolaterally anterior of scutellum. Pleuron black with two yellow maculae, one each on posterior part of posterior anepisternum, on dorsal part of katepisternum. Pile long and white, ventral half of anterior anepisternum with pile 1/2–1/3 as long as pile on adjacent part of dorsal surface of head capsule. Basisternum higher than wide with nearly straight dorsal margin and two triangular lobes on ventral margin (Fig. 55). Scutellum black with anterior 1/3–1/2 yellow. Legs. Coxae and trochanter black; pro- and mesofemur predominantly black, only some yellow basally and apically; basal 1/4–1/3 of metafemur yellow; apical 1/2–3/4 of tibiae black; pro- and mesotarsi dark-yellow to dark-brown; metatarsus dark-brown to black. Femora with black setulae apicodorsally; metatrochanter with black setulae. Procoxa broad, about as wide as long, with demarcated groove confined to the lateral half on dorsal part (Fig. 52); mesofemur with long flattened area antero-basally (Fig. 147); metatrochanter with deep sulcus and broad rim laterally (Fig. 140). Metafemur slightly incrassate and metatibia without appendix on apico-ventral part, elongate (Fig. 155). Wing. Hyaline except for anterior 1/2 to spurious vein and along vein CuA. Vein R4+5 straight with short appendix into cell r4+5. Cross-vein r-m slightly curved. Membrane covered in microtrichia, except anterobasal 1/3 of cell cup with very scattered microtrichia; a narrow area on basal 1/4–1/3 of anal lobe and entire alula bare; alula relatively broad, 2.6–3.0 times longer than wide. Abdomen. Black and yellow coloured. Length of tergite I: II: III: IV is as 1: 2.6–3.1: 3.2–3.5: 3.5–3.9. Width of yellow fascia medially: length of tergite of respectively tergite II, III and IV as 1: 3.7–5.2, 1: 3.7–3.9 and 1: 4.1–4.7. Tergite II about as wide as long, anteromedial part most narrow; length of tergite II: width of tergite II at respectively anterior: narrowest: posterior as 1: 0.81–0.91: 0.69–0.86: 1.1–1.3. Tergite II with triangular maculae on antero-lateral corner, very broadly separated, ratio of black between maculae and width of tergite anteriorly 1: 1.6–2.0; fascia on tergite II and III nearly straight throughout, hardly narrowed towards lateral margin; fascia on tergite IV gradually narrowed towards lateral margin. Tergite IV weakly emarginated. Tergite IV with bow formed grey-white pollinosity mediolaterally, often hardly visible. Sternites I–III with posterior straight yellow fascia. Tergite VIII black pilose. Genitalia. Epandrium with very narrow ventral rim (Figs 161, 163); in dorsal view, cerci narrowly elongate semicircular shaped, with apico-medial sharp pointed projection (Fig. 163), pile about twice as long as width of cerci; surstylus bi-lobed, dorsal lobe broadly elongate apically slightly narrowed and basally with broadened dorsal corner, ventral lobe rhombic-shaped with small membranous basal part (Fig. 161); surstylar apodeme triangular shaped, separated in two elongate trapezoid sclerotized parts (Fig. 164); hypandrium (Figs 161, 165) very broad, rounded and narrowed towards apex; with short ventral lobe and several short sub-ventral projections; superior lobe irregular triangular shaped, articulating with hypandrium; aedeagus with complex structures as in Fig. 162. FEMALE (Figs 121, 129). Body length: 11.5–14.7 mm; wing length: 9.8–11.7 mm. Similar to male, except for normal sexual dimorphism and the following characters. Head (Fig. 137). Head 1.8–2.0 times wider than face just below the antennae. Frontal prominence 0.53–0.65 times longer than wide; relative length of pedicel is as 1.1–1.3: 1: 1.1–1.2. Frons black with lateral yellow maculae along eye margin connected with medially interrupted fascia on anterior part of frons. Dorsal surface of head capsule with large round yellow maculae posterolateral of ocellar triangle and yellow fascia on anterior margin along eyes. Legs. Metafemur and tibia (Fig. 156). Wing. Alula 2.4– 2.8 times longer than wide. Abdomen. Length of tergite I: II: III: IV: V is as 1: 3.1–3.5: 3.5–4.2: 3.3–3.8: 1.5–1.7. Width of yellow fascia medially: length of tergite of respectively tergite II, III and IV as 1: 3.8–4.1, 1: 4.0–5.3 and 1: 4.3–5.2. Tergite II about as wide as long, anteromedial part most narrow; length of tergite II: width of tergite II at respectively anterior: narrowest: posterior as 1:0.84–0.94: 0.74–0.87: 1.4–1.6. Ratio of black between maculae on tergite II and width of tergite II anteriorly 1: 1.9–2.5.
Material examined. 83 Ƌ, 44 ♀, 1 larva (CDFA, CEUA, CNBF, DBV, ENSATS, GPA, IRSNB, JSA, MNHN, MRL, MSD, MSNF, MSNM, MZLCH, NBC, NHM, NHMT, PCV, WSB, ZIN, ZMHB).
Distribution (Fig. 172). Andorra, Austria, Belgium, Finland, France, Germany, Greece, Italy, Morocco, the Netherlands, Poland, Romania, Russia, Serbia, Slovakia, Spain, Sweden, Switzerland, Turkey.
Biology. Adults are found in alluvial soft- and hardwood forests with Populus nigra, riverine gallery forest with Alnus / Salix, Mediterranean Fraxinus angustifolia / Quercus faginea forest or other mature Fagus / Quercus and Mediterranean wet Liquidamber orientalis forest and Quercus suber / Q. pubescens / Pinus nigra forest and also in parks and avenues with old trees like Populus sp. and Aesculus hippocastanum. Males often sit, sometimes during several days, on tree trunks of Aesculus hippocastanum and Populus nigra where also copulation takes place. Females have been caught in an emergency trap placed over a trunk cavity of Fraxinus angustifolia place (Reemer & Smit 2007; Ricarte & Marcos-García 2010; Speight & Castella 2011; Speight 2013). Egg laying behaviour has been observed on Aesculus hippocastanum, Ulmus laevis (Schmid 1994; Speight 2013), Quercus petrea (Radenković et al. 2013) and Quercus cerris. Larvae are found in exuding tree sap on Abies alba and Populus nigra, (Rotheray et al. 2006; Dussaix 2007; Reemer et al. 2009 as Ceriana conopsoides; Ricarte & Marcos-García 2010). Adults are found to feed on flowers of Crataegus sp. and Sorbus sp. (Speight 2013) and the following flowers; Acer sp, Euonymus europeus and white Apiaceae. It has a flight period from mid April to late July, with a peak during May.
Discussion. The type of Ceria subsessilis was not studied as it was not found in ZMHB. The original description of S. subsessilis is clear enough to assign the here studied specimens to this species. It is unclear whether the type of S. subsessilis is really lost and we see no need in designating a neotype at the moment.
description: Published as part of Steenis, Jeroen Van, Ricarte, Antonio, Vujić, Ante, Birtele, Daniele & Speight, Martin C. D., 2016, Revision of the West-Palaearctic species of the tribe Cerioidini (Diptera, Syrphidae), pp. 151-209 in Zootaxa 4196 (2) on pages 198-202, DOI: 10.11646/zootaxa.4196.2.1, http://zenodo.org/record/167924