Eosphaerophoria vietnamensis Mengual, 2010

Mengual, Ximo & Ghorpadé, Kumar, 2010, The flower fly genus Eosphaerophoria Frey (Diptera, Syrphidae), ZooKeys 33 (33), pp. 39-80 : 73-77

Eosphaerophoria vietnamensis Mengual , sp. n.

urn:lsid:zoobank.org:act:6BE779D2-C252-4B44-AE9C-162DD0FDEBAF

Figs 42, 43, 50; MorphBank [http://www.morphbank.net/?id=478084]

Vockeroth 1969: 135, in part as E. dentiscutellata (citation). Mengual et al. 2009: 8, as new species (citation).

Male. Head. Face straight, with distinct round tubercle, yellow, yellow pilose; gena yellow, yellow pilose; lunula yellow; frons completely black on dorsal 2/5 (length between anterior ocellus and lunula), yellow on ventral 3/5 with medial black triangular emargination abruptly narrowed reaching the 1/2 of yellow area, not reaching lunula, with small tubercle dorsally to frontal sulcus elevating vertex, yellow pilose in yellow areas and dark pilose in black areas; dichoptic; vertex and vertical triangle black; ocelli brownish; antenna orange, basoflagellomere dark brown on dorsal 1/2, oval; arista brown; occiput mainly black, yellow ventrally, silvery pollinose and yellow pilose ventrally, black pilose and golden pollinose dorsally.

Thorax. Scutum black, shiny medially, black pollinose laterally, golden brown pilose with yellow pile on notopleuron, yellow laterally with lateral yellow stripe from postpronotum to scutellum, narrower after transverse suture with ventral black area; postpronotum yellow; notopleuron yellow with small posterolateral protuberance, not as evident as in E. dentiscutellata ; scutellum triangular, pointed posteriorly with small blunt tubercle on medial posterior margin, yellow with dorsomedial triangular black area continuing from posterior mesonotum, brownish pilose; propleuron, anepisternum and anepimeron entirely yellow; katepisternum black with a dorsal yellow macula; meron black; katepimeron yellow; katatergum mainly yellow, black posteriorly; calypter dark brown; halter yellowish. Wing. Wing bare basomedially.

Legs. Pro- and mesoleg entirely yellow, except distal part of mesofemur and basal part of mesotibia dark, yellow pilose except tarsi with short black setulae ventrolaterally; metacoxa and trochanter yellow; metafemur yellow basally, black distally on less than 1/2, with 2 ventral rows (one posteroventral and another anteroventral, less evident) of short strong black spine-like setulae on the apical 1/2; metatibia black, black pilose; metatarsus black, black pilose dorsolaterally and golden pilose ventrolaterally.

Abdomen. Fig. 42. Dorsum mainly black, dorsally black pilose, 1st tergum and anterior part of 2nd tergum laterally yellow pilose; 1st tergum black with very narrow yellow fascia on anterior margin following sclerite shape, and lateral yellow margin; 2nd tergum black, yellow on anterior 1/3 of lateral margin continuing the yellow lateral margin of 1st tergum; 3rd tergum black with basal narrow yellow fascia, about 1/5 of tergum length, becoming broader medially and ending in a posteriorly pointed emargination at medial point reaching the 1/3 of tergum length, yellow on anterior 1/2 of lateral margin; 4th tergum similar to 3rd, black with basal broader yellow fascia, about 1/3 of tergum length, produced posteriorly in a medial triangular emargination reaching half length of tergum, yellow on anterior 1/2 of lateral margin; 5th tergum black with 2 anterolateral small yellow maculae, difficult to see on dorsal view; sterna brownish yellow, yellow pilose; 4th sternum with posterior margin produced medially into 2 projections with black setulae; male genitalia as figured ( Fig. 50 ).

Female. Similar to male except for normal sexual dimorphism and: face yellow with medial diffuse black vitta narrowing to tubercle tip not reaching oral apex; lunula black; frons completely black on dorsal 1/4 (length between anterior ocellus and lunula), yellow on basolateral 3/4 with medial broad well-defined black vitta slightly narrowing ventrally (about 3/5 of frons width) and reaching lunula; scutellum without blunt knob on posterior margin, with dorsomedial black area smaller. Metafemur apparently without ventral black setulae except one seen on left metaleg. 1st tergum black with anterior and lateral yellow margin, medially reaching the anterior margin of the 2nd tergum dividing black area in 2 triangular maculae; 3rd abdominal tergum black with basomedial very narrow black fascia and with basal yellow fascia, about 1/5 of tergum length, produced posteriorly in a medial triangular emargination reaching half length of tergum, yellow on anterior 1/2 of lateral margin; 4th abdominal tergum black with basomedial very narrow black fascia and with a basal broader yellow fascia, about 1/3 of tergum length, not produced posteriorly, yellow on anterior 1/2 of lateral margin; 5th abdominal tergum black with 2 basolateral yellow maculae, leaving the medial 1/3 black, yellow on lateral 1/2; 6th abdominal tergum black with 2 anterolateral yellow maculae (Fig. 43); 6th, 7th and 8th sterna with long black pile on posterior margin medially.

Variation. A couple of male specimens have the frons with a medial black very narrow vitta continuing from the abruptly narrowed emargination to lunula. In these cases, this thin vitta reaches lunula, and specimens have the lunula a bit darker medially. Another male individual has no posterior small blunt knob on scutellum, and its posterior margin is more rounded. Some specimens present the metafemur with short black setulae on the apical 2/3, but others on less than apical 1/2. We think that these setulae can be lost in part in dried pinned specimens.

Type locality. VIETNAM: Lam Dong, Dà Lat. 11°56'43.51"N 108°26'31.59"E.

Types. Holotype: “ VIET NAM // Dalat , 1500 m // 11.IX. 1960 ” “ J.L. Gressitt // Collector // BISHOP MUSEUM” “ HOLOTYPE // Eosphaerophoria // vietnamensis // det. X. Mengual 20 09 ” [red, second and third lines handwritten] USNM ENT00036546 [1♁, BPBM] . Paratypes: “ VIET NAM // Dalat , 1500 m // 11.IX. 1960 ” “ J.L. Gressitt // Collector // BISHOP MUSEUM” “ PARATYPE // Eosphaerophoria // vietnamensis // det. X. Mengual 20 09 ” [yellow, second and third lines handwritten] USNM ENT00036031 ,...036547,...036548,...036549 [2♁, BPBM; 2♁, USNM] ; “ VIET NAM // 6km SW, Dalat // 1550 m. // 11.ix.1960 ” “ J.L. Gressitt // Collector” “ PARATYPE // Eosphaerophoria // vietnamensis // det. X. Mengual 20 09 ” [yellow, second and third lines handwritten] USNM ENT00036550 ,...036551 [2♁, USNM] ; “ VIET NAM // Dalat , 1550 m // 11.IX.1960 ” “ J.L. Gressitt // Collector” “ PARATYPE // Eosphaerophoria // vietnamensis // det. X. Mengual 20 09 ” [yellow, second and third lines handwritten] USNM ENT00036552 [1♀, USNM] .

Non-type material. “ MALAY PENINS: // PAHANG, F.M.S. // Fraser’s Hill 4200 ft. // 12.7 .19 36 // H.M. Pendlebury. // F.M.S. Museums.” [fifth and sixth lines in the back] “Ex F.M.S. // Museum // B.M. 1955-354”, “ BMNH ”, “ Loan # // 11849 ” [handwritten] USNM ENT00036553 [1♁, BMNH].

Length (5): body, 4.9–6.1 (5.6) mm; wing, 4.0–4.7 (4.3) mm.

Distribution: Vietnam, Malaysia (?).

Etymology. The specific epithet is derived from the country’s name where the species was found abundantly, Vietnam, and the Latin suffix -ensis denoting place, locality, country, or belonging to, pertaining to ( Brown 1956: 45, 303). Species epithet to be treated as adjective.

Differential diagnosis. Species with 2nd abdominal tergum black dorsally and 2 lateral yellow maculae on 5th tergum, with notopleuron produced posterolaterally. Similar to E. marginata , but Eosphaerophoria marginata has bigger yellow maculae on the 5th abdominal tergum (see Figs 39 and 42) and narrower yellow fasciae on the 3rd and 4th terga. The male genitalia is very similar in these two species, but E. marginata has the right superior lobe broader and without a posterior tooth ( Fig. 48 ) being very different from left superior lobe. Eosphaerophoria vietnamensis also has asymmetrical superior lobes, but the right superior lobe has a posterior tip or tooth and is thinner in the posterior section than that in E. marginata (see Fig. 50b ).

Remarks. Eosphaerophoria vietnamensis and E. symmetrica were both collected in Vietnam, but they can be easily differentiated by the abdominal pattern (see Figs 11, 22, 23) and male genitalia (see Figs 49 , 50 ).

The Malaysian specimen, collected in the same area of type locality for E. brunettii , is tentatively included in this species based on colour pattern of 1st and 2nd abdominal terga, the lateral yellow stripe of the scutellum and the metaleg. But because the posterior part of abdomen and male genitalia are lost, it can not be identified with certainty.

Conclusions

A total of eight new Eosphaerophoria species were described in this study, totalling 11 known species. Previous authors ( Vockeroth 1969; Claussen and Weipert 2003) cited most of the studied specimens as undescribed or identified as other species. In this work, we reported three new specimens of Eosphaerophoria . Two of them belong to new species described from Indonesia and Malaysia ( Eosphaerophoria hermosa , E. brunettii ), constituting the first material examined of this genus from these countries. The third specimen never cited before was identified as E. vietnamensis , also from Malaysia. With these three new records, a total of just 25 specimens (16♁ 9♀) of Eosphaerophoria are known today.

The other new species were described from material published under different names. Vockeroth (1969) grouped some specimens of the new species described here under a different name. His concept of E. dentiscutellata has been shown here to include two new species, E. vietnamensis and E. symmetrica . Vockeroth (1969) also examined a new species from Papua New Guinea, but he did not describe it. In this revision, four new species were described from Papua New Guinea: E. adornata , E. bifida , E. luteofasciata and E. nigrovittata .

Eosphaerophoria is a unique and “aberrant” (fide Vockeroth 1969) endemic in the Australasian and Oriental Regions. Specimens of this genus are found in five different Biodiversity hotspots (sensu Myers et al. 2000), including Sundaland, Wallacea, Philippines, Indo-Burma and Sri Lanka. However, New Guinea is not included in any hotspot but is the area with the highest number of described species. This presence in very biodiverse regions prompts us to consider that more new species of this genus could be sampled in the future, especially by operating Malaise traps which have taken most of the presently known specimens. More collecting effort in this area, especially New Guinea Island, is needed to understand the diversity of Diptera (including Syrphidae ), which probably is underestimated due to the low number of field surveys; most of them carried out in the mid 20th century.

Acknowledgments

We thank Brian Cogan, Ken Smith, Adrian Pont and Richard Vane-Wright, The Natural History Museum [formerly the British Museum (Natural History)], London (BMNH); W. Hackman, B. Lindeberg and Gunilla Ståhls, Zoological Museum, Finnish Museum of Natural History, University of Helsinki, Helsinki (UZMH); Rob de Vries and Gerard Pennards, Nationaal Natuurhistorische Museum, Leiden (RNH); Neal Evenhuis, Bishop Museum, Honolulu (BPBM); Daniel Burckhardt, Naturhistorisches Museum Basel, Basel (NMB); besides Leif Lyneborg, Borge Petersen and Thomas Pape, Zoologisk Museum, Copenhagen (UZMC), for permission to study material in their care [other collection acronyms used are: USNM for United States National Museum, Washington].

We are also grateful to Jeffrey Cumming and Jeffrey Skevington (Canadian National Collection of Insects, Arachnids and Nematodes, Ottawa) and Matthias Hartmann (Naturkundemuseum Erfurt, Erfurt) for permission to reproduce illustrations from Vockeroth (1969) [Figs 11, 12, 13, 16, 17, 18, 22, 48] and from Claussen and Weipert (2003) [Figs 23, 25, 26, 27, 30]. We also thank Martin Hauser and Jeff Skevington for their helpful review and comments.

We thank the Smithsonian Institution for our Postdoctoral fellowships at the National Museum of Natural History, as well as the Schlinger Foundation for financial support. We are much obliged to F. Christian Thompson for his continuous support and valuable advice during our taxonomic careers and also for his erudite comments on working drafts of this manuscript.

Figures

Figure 48. Eosphaerophoria marginata, male genitalia a left lateral view b sternite 9, superior lobes and aedeagus, right lateral view c left and right superior lobes, lateral view, outline only d left surstylus, dorsal view e sternite 9, superior lobes and aedeagus, ventral view (adapted from Vockeroth 1969).

Figure 49. Eosphaerophoria symmetrica, male genitalia a left lateral view b right superior lobe, dorsal view c tergite 9, cerci and surstyli, dorsal view.

Figure 50. Eosphaerophoria vietnamensis, male genitalia a left lateral view b right superior lobe, lateral view c right superior lobe, dorsal view d left superior lobe, dorsal view e tergite 9, cerci and surstyli, dorsal view.