Sphegina (Asiosphegina) spathigera, 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 : 162-165

Sphegina (Asiosphegina) spathigera sp. nov.

urn:lsid:zoobank.org:act:FDBA2015-5C39-4069-B719-60FAE1EE8982

Figs 77F , 82 D–E, 83, 84K, 88A

Differential diagnosis

Similar to Sphegina (Asiosphegina) amplistylus sp. nov., S. (A.) inflata sp. nov. and S. (A.) philippina . Except for the characters mentioned in the key it is distinguished by the wide bilobed apex of the dorsal lobe of surstylus on both sides (narrow, unilobed in the other species).

Etymology

The specific epithet is from the Latin ‘ spathigera ’, meaning ‘bearing a short pointless sword’ and referring to that kind of lobe posterolaterally on the left side of male sternum IV.

Material examined

Holotype

PHILIPPINES • ♂; “ Philippines / Ifugao Province / Jacmal Bunhian / 4 km E Mayoyao 800– / 1000 m 1–10.V.1967 ”; “ H.M. Torrevillas / Collector / Bishop”; BPBM.

Description

Male

LENGTH. Body 5.6 mm, wing 4.2 mm.

HEAD. Face in lateral view concave, weakly projected antero-ventrally; frontal prominence very weakly developed. Ratio width of vertex at anterior ocellus: width of head 1: 5.2; ratio width of ocellar triangle: width of vertex 1: 1.5; ratio length of ocellar triangle: length of frons 1: 2.5. Face black, ventral half dark yellow to brown, light grey pollinose, long pilose along eye-margin. Hypostomal bridge dark brown, long pale pilose. Gena and mouth edge brown to dark brown, pale pollinose with large subtriangular nonpollinose shiny area. Frons and vertex black, slightly pollinose, a narrow subtriangular area posterior of lunula non-pollinose and shiny ( Fig. 88A ); pile short, light yellow. Frons with weak furrow medially. Occiput black, light grey pollinose, light yellow pilose. Eye with an area of enlarged facets at anterior margin. Antenna brown with black setae dorsally on scape and pedicel; basoflagellomere rectangular, ratio width: length 1: 1.4; arista long pilose, nearly 3 times as long as basoflagellomere.

THORAX. Colour black, weakly greyish pollinose, postpronotum dark brown, grey pollinose, pleuron entirely more heavily grey pollinose; scutum and pleuron with very short adpressed light yellow pile. Scutellum short and widely sub-triangular, black, weakly pale pollinose, long pilose, with pile longer than on scutum, without marginal setae, possibly the setae are broken off.

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

1

meeting vein R

4+5

perpendicularly.

LEGS. Pro- and mesoleg yellow, tarsomeres 4–5 black, tarsomere 3 of protarsus brown. Metaleg with coxa black, trochanter yellow; femur black with basal ⅓ yellow, strongly incrassate, ratio width: length 1: 3.1; tibia black and yellow biannulate with large rounded apicoventral dens; tarsus entirely black, basitarsomere thick, ratio width: length 1: 3.2.

ABDOMEN. Length ratio of terga I: II: III: IV 1: 4.0: 2.1: 1.6; ratio width at posterior margin: medial length of tergum II and III 1: 2.5 and 1: 0.7. Terga black, anterior ⅓ of tergum III with dark yellow fascia; pile pale, on terga short, laterally on terga I and II long; tergum I with horizontal row of 3–4 evenly spread brown-yellow setae at lateral margin; sternum III not sclerotized; sternum IV, Fig. 83A ; sterna VI, VII and VIII simple, with long yellow pile. Genitalia, Fig. 83 B–D: note the almost symmetrical surstyli and asymmetrical superior lobes.

Female

Unknown.

Remarks

In the type material of Sphegina (Asiosphegina) philippina there is one specimen (1 ♀, “P.I.: Mindanao / Bukidnon. 1480 m. / Mt. Katanglad / 27–31.X.1959 ”, “L.W. Quate / Collector” (BPBM)) which is not S. (A.) philippina because the vertex ( Fig. 84K ) is wide (narrower in S. (A.) philippina ), the postpronotum is black (yellow in S. (A.) philippina ) and the wing is hyaline (infuscated in S. (A.) philippina ). It is possible that this specimen is the female of S. (A.) spathigera sp. nov., but as even the males of the species similar to S. (A.) philippina are very difficult to distinguish from each other without reference to the genitalia the identity of this female remains open.

Figures

Fig. 77. Tergum I, dorsal view (A, E–F) and lateral view (B–D). A. Sphegina (Asiosphegina) mirifica Hippa, van Steenis & Mutin, 2015, ♀, Myanmar. B. S. (A.) nigerrima Shiraki, 1930, Ƌ, Taiwan. C. S. (A.) bispinosa Brunetti, 1915, Ƌ, Nepal. D. S. (A.) philippina Thompson, 1999, paratype, ♀, Philippines. E. S. (A.) raduloides Hippa, van Steenis & Mutin, 2015, paratype, Ƌ, Myanmar. F. S. (A.) cf. spathigera sp. nov., ♀, Philippines. Scale bars = 0.5 mm.

Fig. 82. Habitus, lateral view. A. Sphegina (Asiosphegina) siculifera Hippa, van Steenis &Mutin, 2015, paratype, Ƌ, Myanmar. B. S. (A.) simplex Hippa, van Steenis & Mutin, 2015, paratype, Ƌ, Myanmar. C. S. (A.) sinesmila Hippa, van Steenis & Mutin, 2015, paratype, Ƌ, Myanmar. D. S. (A.) spathigera sp. nov., holotype, Ƌ, Philippines. E. S. (A.) cf. spathigera sp. nov., ♀, Philippines. F. S. (A.) strigillata sp. nov., paratype, Ƌ, Vietnam. Scale bars = 1.0 mm.

Fig. 88. Head. lateral view (C, E, F, J) and dorsal view (A–B, D, G–I, K–L). A. Sphegina (Asiosphegina) spathigera sp. nov., holotype, Ƌ, Philippines. B–C. S. (A.) spenceri sp. nov., paratype, Ƌ, Vietnam. D–E. S. (A.) strigillata sp. nov., holotype, Ƌ, Vietnam. F. S. (A.) tricoloripes, Brunetti, 1915, ♀, India. G. S. (A.) tricoloripes, Ƌ, India. H. S. (A.) umbrosa sp. nov., holotype, Ƌ, China. I. S. (A.) varidissima Shiraki, 1930, Ƌ, Taiwan. J. S. (A.) varidissima, ♀, Taiwan. K. S. (A.) verrucosa sp. nov., paratype, Ƌ, Vietnam. L. S. (A.) vietnamensis sp. nov., paratype, Ƌ, Vietnam. Scale bars = 0.5 mm.

Fig. 83. Sphegina (Asiosphegina) spathigera sp. nov., holotype, Ƌ. A. Posterior part of sternum IV, ventral view. B. Left surstylus, lateral view. C. Left superior lobe with associated parts, lateral view. D. Genitalia, right side, lateral view. Scale bars = 0.5 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.