Revision of the West-Palaearctic species of the tribe Cerioidini (Diptera, Syrphidae) Author Steenis, Jeroen Van Author Ricarte, Antonio Author Vujić, Ante Author Birtele, Daniele Author Speight, Martin C. D. text Zootaxa 2016 4196 2 151 209 journal article 10.11646/zootaxa.4196.2.1 791720e1-fd69-4485-b49c-5b377412ecf1 1175-5326 167924 68A88A77-E760-4293-BE95-AA2785DE3C0C Ceriana glaebosa van Steenis & Ricarte sp. n. Figs 5, 6 , 23, 24 , 41 , 67 , 76–82 , 169 Ceriana vespiformis : Dirickx (1994) , in part; Speight (2013) , in part. Diagnosis . C. glaebosa is the only known West-Palaearctic Ceriana species with evenly-intermixed yellow and black pile on the mesofemur apico-posteriorly. It can be separated from the similar C. vespiformis by: eye contiguity very short, about 1/3 of the frons length (in C. vespiformis about 2/3); dorsal surface of head capsule yellow, posterior to ocelli narrower or with a squarish black macula (in C. vespiformis , dorsal surface of head capsule entirely yellow); fascia on tergite III straight, only narrowed at lateral margin of tergite (in C. vespiformis gradually narrowed towards lateral margin); fascia on tergite IV nearly reaching lateral margin (in C. vespiformis occupying only about 2/3 of the width); each of tergites III and IV with a medial bump, which is clearly differentiated from the rest of the tergite surface in cross-section (in C. vespiformis without bump, sometimes with mediolateral depression giving the impression of having a bump); sternite III with a concave yellow fascia on the posterior margin (in C. vespiformis fascia straight or absent); cercus more triangular (in C. vespiformis more elongate); surstylus shorter, with broader base and evenly rounded apex. Description . MALE ( Figs 5 , 23 ). Body length: 8.2–10.1 mm ; wing length: 6.1–7.2 mm . Head ( Fig. 41 ). Face slightly protruding antero-ventrally with weakly demarcated tubercle and slightly concave below antennae. Head 2.2–2.3 times wider than face just below the antennae; width of facial vitta 0.16–0.24 times as wide as width of face; length of eye contiguity 0.28–0.33 times as long as length of frons; angle of eyes at eye contiguity 105–110o. Face yellow, a rectangular vitta from eye margin to mouth edge, a medial vitta not reaching the mouth edge and a fascia at frontal prominence black; sometimes hypostomal bridge black. Frons yellow, sometimes with a small posterior black triangle. Vertical triangle black to yellow. Ocellar triangle black; dorsal surface of head capsule yellow, posterior to ocelli narrowed or with a squarish black macula. Frontal prominence 4.2–5.6 times longer than wide; relative length of pedicel is as 1.0–1.1: 1: 0.63–0.68. Antennae and frontal prominence brown-yellow to black coloured; arista white pilose. Thorax . Scutum with yellow maculae on postpronotum and notopleuron, sometimes yellow oval vittae between postalar callus and transverse suture laterally. Pleuron black with three yellow maculae, one each on posterior 1/2–3/5 of posterior anepisternum, on dorsal 1/4–1/3 of katepisternum and on anepimeron. Metasternum with short pile and a low, rounded elevation medially on antero-ventral part. Scutellum entirely yellow. Legs . Coxae and trochanter black; apical 1/4–1/3 of pro- and mesofemur black; apical 1/ 5–1/3 of metafemur black; apico-medial 1/5–1/3 of tibiae black; tarsi dark-brown to black, sometimes first 2 tarsomeres of pro- and mesotarsus brown-yellow to yellow; in light coloured specimens legs predominantly yellow. Pile on apico-posterior part of mesofemur long and mixed yellow and black; metatrochanter without setulae. Mesotrochanter straight dorsally; mesofemur without a flattened area antero-basally; metatrochanter with a weak sulcus and narrow rim laterally ( Fig. 67 ). Metatibia without appendix on apico-ventral part; metafemur elongate and slightly curved. Wing . Hyaline except for anterior 1/2, along vein R4+5, and along spurious vein. Loop in vein R4+5 weak with short appendix. Cross-vein r-m slightly curved. Membrane entirely covered in microtrichia. Alula relatively narrow, 3.3–4.0 times longer than wide. Abdomen . Black and yellow coloured. Length of tergite I: II: III: IV is as 1: 1.3–1.5: 1.7–2.0: 1.8–1.9. Width of yellow fascia medially: length of tergite of respectively tergite II, III and IV as 1: 2.7–3.5, 1: 4.0–4.2 and 1: 2.7–3.3. Tergite II wider than long, anterior part most narrow; length of tergite II: width of tergite II at respectively anterior: posterior as 1: 1.1–1.3: 1.4–1.6. Tergite I with large triangular yellow maculae on antero-lateral corner, very broadly separated medially to nearly connected; fascia on tergite II straight, gradually narrowing towards lateral margin; fascia on tergite III straight, only narrowed at lateral margin; fascia on tergite IV straight, gradually narrowing towards the lateral margin and nearly reaching it; tergite II in some specimens with yellow posterolateral maculae. Tergite IV weakly emarginated. Tergite I with rather high medial elevation; tergites III and IV with very clear and high longitudinal elevation; with vague grey-white pollinosity medio-laterally. Sternites I–III with posterior yellow fascia, the one on sternite III with concave margin. Genitalia . Epandrium with narrow ventral rim ( Figs 76, 77, 78, 81 ); in dorsal view, cerci broadly triangular shaped, with round elevated baso-medial part ( Fig. 78 ), pile about half as long as width of cerci; surstylus bi-lobed, dorsal lobe short, broadly elongate with slightly narrow base, ventral lobe rather narrowly circular with membranous basal part ( Figs 76, 77, 81 ); surstylar apodeme narrow, circular shaped ( Fig. 80 ); hypandrium with broad base and narrower apex; with very short, broad lingula; superior lobe irregular circular shaped, articulating with hypandrium ( Figs 77, 82 ); aedeagus with elongated and pointed projection baso-ventrally, apex with three projections, dorsally short and sharply pointed, medially a short rectangle and ventrally short slightly broad and pointed ( Fig. 79 ). FEMALE ( Figs 6 , 24 ). Body length: 8.4–10.8 mm ; wing length: 6.6–8.6 mm . Similar to male, except for normal sexual dimorphism and the following characters. Head . Head 2.1–2.2 times wider than face just below the antennae; width of facial vitta 0.18–0.21 time as wide as width of face. Frontal prominence 4.9–5.6 times longer than wide; relative length of pedicel is as 1.0–1.1: 1: 0.75–0.86. Medial facial vitta somewhat narrower, sometimes with light medial vitta enclosed. Frons with entire yellow fascia; vertex black sometimes with yellow triangular macula medially. Wing . Alula relatively narrow, 2.7–3.2 times longer than wide. Abdomen . Length of tergite I: II: III: IV: V is as 1: 1.5–1.6: 2.2–2.4: 2.0–2.1: 0.69–0.79. Width of yellow fascia medially: length of tergite of respectively tergite II, III and IV as 1: 2.9–3.2, 1: 4.0–4.5 and 1: 2.4–2.9. Tergite II wider than long, anterior part most narrow; length of tergite II: width of tergite II at respectively anterior: posterior as 1: 1.4–1.5: 1.8–1.9. Variation . There appear to be two colour phenotypes: yellow in the autumn generation and black in the spring generation. However, a yellow spring specimen and a black autumn specimen are known to the authors of the present paper. In the future DNA analysis might help to clarify whether these two phenotypes correspond to separate taxa or not. Type material . HOLOTYPE Ƌ; Cyprus : " Cyprus / Limassol / 3-v-1958 / [leg] G. Mavromoustakis ", " R. I. Sc. N. B. 24.236 / coll. M. Bequaert ", " J. Skevington / [ BOLD DNA voucher] Specimen # / 31493", " Holotype Ƌ / Ceriana glaebosa / van Steenis & Ricarte 2016" [red label] ( IRSNB ) . PARATYPES : 13 Ƌ, 18 ♀ : Cyprus : " Cyprus / Limassol / 3-v-1958 / [leg] G. Mavromoustakis ", " R. I. Sc. N. B. 24.236 / coll. M. Bequaert " ( 1 ♀ IRSNB ) ; " Cyprus / Limassol / 5-v-1958 / [leg] G. Mavromoustakis ", " R. I. Sc. N. B. 24.236 / coll. M. Bequaert " (1 Ƌ FSUNS , 1 ♀ CEUA ) ; " Cyprus / Limassol / 5-v-1958 / [leg] G. Mavromoustakis ", " R. I. Sc. N. B. 24.236 / coll. M. Bequaert ", " J. Skevington / [ BOLD DNA voucher] Specimen # / 31494" ( 1 ♀ CNC ) ; " Cyprus / Limassol / 7.V.1934 / [leg.] G. Mavromoustakis / B.M. 1934-416" ( 1 ♀ JSA ) ; " Cyprus / Limassol / 9.V.1934 / [leg.] G. Mavromoustakis / B.M. 1934-416" (1 Ƌ NHM , 1 Ƌ JSA ) ; " Cyprus / Limassol / 10.V.1934 / [leg.] G. Mavromoustakis / B.M. 1934-416" ( 1 ♀ ZIN ) ; " Cyprus / Limassol / 11.V.1934 / [leg.] G. Mavromoustakis / B.M. 1934-416" ( 1 ♀ NHM ) ; " Cyprus / Limassol / 17.V.1934 / [leg.] G. Mavromoustakis / B.M. 1934-416" (1 Ƌ ZIN ) ; " Cyprus / Limassol 30.V.1949 / [leg.] G.A. Mavromoustakis / B.M. 1950-221" (1 Ƌ NHM ) ; " Cyprus / Limassol / X.1933 / [leg.] G. Mavromoustakis / B.M . 1934-75 " (1 ♀ NHM); " Limassol / Cyprus / coll. G. Mavromou- / stakis 25.4.1955 ", " R. I. Sc. N. B. 24.236 / coll. M. Bequaert " (1 Ƌ IRSNB ) ; " Limassol / Cyprus / coll. G. Mavromou- / stakis 26.4.1955 ", " R. I. Sc. N. B. 24.236 / coll. M. Bequaert " ( 1 ♀ IRSNB ) ; " Cyprus / coll. G. Mavromou- / stakis 27.9.1953 / Limassol ", " R. I. Sc. N. B. 24.236 / coll. M. Bequaert " ( 1 ♀ IRSNB ) ; " Cyprus / Episcopi / 29.V.1937 / [leg.] G.A. Mavromoustakis / B.M. 1937-808" ( 1 ♀ NHM ) ; " Cyprus Lania / 1800 ft 13-vi-1961 / [leg] G. Mavromoustakis ", " R. I. Sc. N. B. 24.236 / coll. M. Bequaert " (1 Ƌ IRSNB ) ; " Cherkes / Cyprus / 23.7.1951 / coll. G. Mavromoustakis ", " R. I. Sc. N. B. 24.236 / coll. M. Bequaert ", " J. Skevington / [ BOLD DNA voucher] Specimen # / 31495" (1 Ƌ JSA ) ; " Yermasogia riv. / Cyprus / coll. G. Mavromou- / stakis 5.9.[19]56", " R. I. Sc. N. B. 24.236 / coll. M. Bequaert ", " J. Skevington / [ BOLD DNA voucher] Specimen # / 31496" ( 1 ♀ CNC ) ; " Yermasogia riv. / Cyprus / coll. G. Mavromou- / stakis 9.9.[19]55", " R. I. Sc. N. B. 24.236 / coll. M. Bequaert " (1 Ƌ CEUA , 1 ♀ IRSNB ) ; " Yermasogia riv. / Cyprus / coll. G. Mavromou- / stakis 12.9.[19]55", " R. I. Sc. N. B. 24.236 / coll. M. Bequaert " (1 Ƌ IRSNB ) ; " Cyprus Yermasagin / riv. 10-IV-1957 / G. Mavromoustakis ", " R. I. Sc. N. B. 24.236 / coll. M. Bequaert " ( 1 ♀ IRSNB ) ; " Cyprus Yermasagin / riv. 20-VIII-1955 / G. Mavromoustakis ", " R. I. Sc. N. B. 24.236 / coll. M. Bequaert " (1 Ƌ CNC , 3 ♀ IRSNB , 1 ♀ FSUNS , 1 ♀ JSA ) ; " Cyprus Yermasagin / riv. 6-X-1950 / G. Mavromoustakis ", " R. I. Sc. N. B. 24.236 / coll. M. Bequaert " (1 Ƌ IRSNB , 1 Ƌ NBC ) . Distribution ( Fig. 169 ). Cyprus . Etymology . The epithet ‘glaebosa’ means ‘lumpy' in Latin and refers to the medial bump on the tergites III and IV. Biology . Adults fly from early April to mid June and from mid August to early October. Larva unknown.