Sphegina (Asiosphegina) prolixa, Steenis & Hippa & Mutin, 2018

Steenis, Jeroen Van, Hippa, Heikki & Mutin, Valeri A., 2018, Revision of the Oriental species of the genus Sphegina Meigen, 1822 (Diptera: Syrphidae), European Journal of Taxonomy 489, pp. 1-198 : 153-155

Sphegina (Asiosphegina) prolixa sp. nov.

urn:lsid:zoobank.org:act:CD691191-6E81-42FC-8F1F-42619911DB72

Figs 75D , 78 , 79B , 84 I–J

Differential diagnosis

In the non-genitalic characters the species is similar to Sphegina (Asiosphegina) ghatsi sp. nov. and is distinguished by the characters given in the key. In the male genitalia the species are not especially similar. Sphegina (Asiosphegina) prolixa sp. nov. is easily distinguished from S. (A.) ghatsi sp. nov., as well as any other known Sphegina , by the narrow and extremely long sublobe posteroventrally on its superior lobe.

Etymology

The specific epithet is from the Latin ‘ prolixa ’, meaning ‘stretched out or long’ and referring to the exceedingly long posteroventral lobe on the male right-side superior lobe.

Material examined

Holotype

MALAYSIA • ♂; “ W. Malaysia: / Selangor / [leg] A.E. Stubbs / BMNH 1974–87 ”; “Genting Tea Estate / Genting Sembah, / forest 2000 feet / 24–27.xii.1972 ”; terga III–VIII and the long thin extension of the superior lobe missing; NHM.

Paratype

THAILAND • 1 ♂; “Thailand: Chiang Mai Pt. Doi Inthanon / National Park Huai Sai Leung yellow falls; / 18°31 ʹ N, 98°27 ʹ E; 1000 m; 3–12.III.2002; / Malaise trap ”; QSBG .

Description

Male

LENGTH. Body 5.2 mm, wing 3.4–3.9 mm.

HEAD. Face in lateral view concave, weakly projected antero-ventrally; frontal prominence weakly developed. Ratio width of vertex at anterior ocellus: width of head 1: 4.5–4.7; ratio width of ocellar triangle: width of vertex 1: 1.4–1.5; ratio length of ocellar triangle: length of frons 1: 1.7–2.0. Face black, light grey pollinose, long pilose along eye-margin. Hypostomal bridge black, long pale pilose. Gena and mouth edge black, pale pollinose with large subtriangular non-pollinose shiny area. Frons and vertex black; with dense velvet-black pollinosity, with an oval area posterior of lunula non-pollinose and shiny, with subtriangular grey pollinose lateral macula posteriorly from shiny area ( Fig. 84I ); pile short, light yellow. Frons with narrow and weak furrow medially. Occiput black, light grey pollinose, light yellow pilose. Eye with an area of slightly enlarged facets at anterior margin ( Fig. 84J ). Antenna with scape and pedicel dark brown, basoflagellomere light-brown, with black setae dorsally on scape and pedicel; basoflagellomere rectangular, ratio width: length 1: 1.3–1.4; arista nearly bare, 3.5 times as long as basoflagellomere.

THORAX. Colour black, weakly greyish pollinose; posterior margin of katepisternum narrowly nonpollinose, shiny; scutum and pleuron with very short adpressed light yellow pile. Scutellum semicircular, black, shiny medially and weakly pale pollinose laterally, with pile slightly longer than on scutum, without marginal setae, probably broken off.

WING. Entirely microtrichose; hyaline, stigma yellowish. Crossvein dm-cu meeting vein M almost perpendicularly and vein M

1

meeting vein R

4+5

perpendicularly.

LEGS. Pro- and mesoleg with femur dark yellow on medial ¼– ⅓; tibia with dark brown annulus on apicomedial 1/5– ⅓ and tarsomere 1 on apical half and entire tarsomeres 3–5 and in paratype also tarsomere 2 black. Metaleg with coxa black, trochanter yellow; femur black with basal 1/5–¼ yellow, incrassate, ratio width: length 1: 3.2–3.4; tibia yellow with apical half dark brown to black, with long and wide apicoventral dens; tarsus entirely black, basitarsomere thick, ratio width: length 1: 3.0–3.4.

ABDOMEN. Length ratio of terga I: II: III: IV 1: 3.1–3.7: 1.8: 1.7; ratio width at posterior margin: medial length of tergum II and III 1: 3.6–4.0 and 1: 0.8. Terga black, anterior ⅜ of tergum III with yellow fascia; tergum IV with narrow elongate dark brown macula along anterolateral margin; pile pale, on terga short, laterally on terga I and II long; tergum I with horizontal row of 4–6 irregularly placed light yellow setae at lateral margin; sternum III not sclerotized; sternum IV, Fig. 78C ; sterna VI, VII and VIII simple, with long yellow pile. Genitalia, Fig. 78 A–B, D–F: note the symmetrical surstyli and asymmetrical superior lobes.

Female

Unknown.

Remarks

Among the material studied a female (1 ♀; “ Thailand: Chiang Mai Prov. / Chiang Mai Botanical Garden QSBG / 18.8955° N, 98.8636° E / 11–25.VII.2013, coll M. Hauser” (CSCA)) was found which may belong to this species.

Figures

Fig. 75. Habitus, lateral view. A. Sphegina (Asiosphegina) plautus sp. nov., paratype, Ƌ, China. B. S. (A.) plautus sp. nov., paratype, ♀, China. C. S. (A.) pollinosa Hippa, van Steenis & Mutin, 2015, paratype, Ƌ, Myanmar. D. S. (A.) prolixa, sp. nov., paratype, Ƌ, Thailand. E. S. (A.) radula Hippa, van Steenis & Mutin, 2015, paratype, Ƌ, Myanmar. F. S. (A.) setosa sp. nov., paratype, Ƌ, Nepal. Scale bars = 1.0 mm.

Fig. 78. Sphegina (Asiosphegina) prolixa sp. nov., holotype, Ƌ (A–B) and paratype, Ƌ (C–F). A, D. Left surstylus, lateral view. B, F. Genitalia, right side, lateral view. C. Sternum IV, ventral view. E. Left superior lobe, lateral view. Scale bars = 0.5 mm.

Fig. 79. Habitus, dorsal view. A. Sphegina (Asiosphegina) pollex Hippa, van Steenis & Mutin, 2015, paratype, Ƌ, Myanmar. B. S. (A.) prolixa, sp. nov., paratype, Ƌ, Thailand. C. S. (A.) radula Hippa, van Steenis & Mutin, 2015, paratype, Ƌ, Myanmar. D. S. (A.) radula, paratype, ♀, Myanmar. E. S. (A.) raduloides Hippa, van Steenis & Mutin, 2015, paratype, Ƌ, Myanmar. F. S. (A.) siculifera Hippa, van Steenis & Mutin, 2015, paratype, Ƌ, Myanmar. Scale bars = 1.0 mm.

Fig. 84. Head, lateral view (E, H), dorsal view (A–D, F, I, K–L) and frontal view (G, J). A. Sphegina (Asiosphegina) nasuta Hippa, van Steenis & Mutin, 2015, paratype, Ƌ, Myanmar. B. S. (A.) nubicola sp. nov., holotype, Ƌ, Thailand. C. S. (A.) orientalis Kertész, 1914, ♀, Taiwan. D. S. (A.) parvula Hippa, van Steenis & Mutin, 2015, paratype, Ƌ, Myanmar. D–E. S. (A.) perlobata sp. nov., holotype, Ƌ, Taiwan. F. S. (A.) philippina, Thompson, 1999, paratype, ♀, Philippines. G. S. (A.) philippina, holotype, Ƌ, Philippines. H. S. (A.) plautus sp. nov., holotype, Ƌ, China. I–J. S. (A.) prolixa sp. nov., holotype, Ƌ, Malaysia. K. S. (A.) cf. spathigera sp. nov., ♀, Philippines. L. S. (A.) taiwanensis sp. nov., paratype, Ƌ, Taiwan. Scale bars = 0.5 mm.